European Journal of Cardiovascular Nursing http://cnu.sagepub.com/
The Cardiac Self-Efficacy Scale, a useful tool with potential to evaluate person-centred care Andreas Fors, Kerstin Ulin, Christina Cliffordson, Inger Ekman and Eva Brink Eur J Cardiovasc Nurs published online 22 August 2014 DOI: 10.1177/1474515114548622 The online version of this article can be found at: http://cnu.sagepub.com/content/early/2014/08/21/1474515114548622
Published by: http://www.sagepublications.com
On behalf of:
European Society of Cardiology
Additional services and information for European Journal of Cardiovascular Nursing can be found at: Email Alerts: http://cnu.sagepub.com/cgi/alerts Subscriptions: http://cnu.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav
>> OnlineFirst Version of Record - Aug 22, 2014 What is This?
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
548622 research-article2014
CNU0010.1177/1474515114548622European Journal of Cardiovascular Nursing 0(0)Fors et al.
EUROPEAN SOCIETY OF CARDIOLOGY ®
Original Article
The Cardiac Self-Efficacy Scale, a useful tool with potential to evaluate person-centred care
European Journal of Cardiovascular Nursing 1–8 © The European Society of Cardiology 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1474515114548622 cnu.sagepub.com
Andreas Fors1,2, Kerstin Ulin1,2, Christina Cliffordson3, Inger Ekman1,2 and Eva Brink1,2,3
Abstract Background: Cardiac self-efficacy is a person’s belief in his/her ability to manage the challenges posed by a coronary disease, and its role has been evaluated in several coronary populations using the Cardiac Self-Efficacy Scale (CSE Scale). Self-efficacy has an important role in person-centred care, however there is a lack of appropriate instruments that evaluate person-centred interventions. Aim: The purpose of this study was to validate the CSE Scale by examining its psychometric properties as a first step in evaluating a person-centred care intervention in persons with acute coronary syndrome (ACS). Methods: The study sample consisted of 288 persons (72 women, 216 men) who completed the Swedish version of the CSE Scale two months after hospitalisation for an ACS event. Construct validity was psychometrically evaluated using confirmatory factor analysis. Additionally, convergent and discriminant validity were tested using correlation analyses. Results: The results revealed that the CSE Scale was represented by three dimensions (control symptoms, control illness and maintain functioning). The analyses also showed that the CSE Scale is suitable for providing a total summary score that represents a global cardiac self-efficacy dimension. Evaluation of convergent and discriminant validity showed the expected correlations. Conclusion: The CSE Scale is a valid and reliable measure when evaluating self-efficacy in patients with ACS. It also seems to be a useful tool to promote person-centred care in clinical practice since it may offer useful guidance in the dialogue with the patient in the common creation of a personal health plan. Keywords Acute coronary syndrome, myocardial infarction, patient-centered care, person-centred care, psychometric validation, self-efficacy Date received: 3 February 2013; revised: 4 July 2014; accepted: 4 August 2014
Introduction The number of survivors of coronary heart disease (CHD) is increasing in most of the northern and western European countries.1 These survivors frequently report persistent symptoms such as fatigue,2 pain, anxiety and depression,3 which together lead to reduced quality of life.2,3 The outcome of recovery after myocardial infarction is unpredictable and dependent on several factors, such as clinical status and psychological factors e.g. anxiety4 and depression5 which are associated with adverse cardiac events and mortality.4,5 One factor that has been shown to play an important role in recovery is self-efficacy.2 The concept of self-efficacy derives from social cognitive theory and concerns people’s belief in
their ability to influence events that affect their lives.6 This approach is crucial in person-centred care, which
1Institute
of Health and Care Sciences, University of Gothenburg, Sweden 2Centre for Person-Centred Care (GPCC), University of Gothenburg, Sweden 3Department of Nursing, Health and Culture, University West, Trollhättan, Sweden Corresponding author: Andreas Fors, Institute of Health and Care Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. Email address: [email protected]
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
2
European Journal of Cardiovascular Nursing
stresses the importance of knowing the patient also as a person and addresses his/her human capacities, wishes and needs.7 General self-efficacy refers to the belief in one’s ability to respond to challenges in general, and it has also been operationalised for use in a validated8 and internationally used questionnaire.9 In addition, several attempts have been made to develop measurements targeting specific areas of self-efficacy that are associated with beneficial outcomes. For instance, a positive relationship has been reported between self-efficacy related to diabetes mellitus type 2 and adherence to physical activity and healthy food choices.10 Another study showed that patients’ initial beliefs about their illness being controllable predicted exercise self-efficacy over a three-year period.11 To examine the role of self-efficacy in addressing the challenges that arise as a result of coronary disease, regarding both function and symptom interpretation, Sullivan and co-workers developed the Cardiac Self-Efficacy Scale (CSE Scale).12 Cardiac self-efficacy refers to a person’s confidence in his/her ability to manage illness-specific outcomes. The CSE Scale consists of two dimensions: the first represents a person’s confidence that he/she can control symptoms (eight items) and the second a person’s confidence that he/she can maintain functioning (five items).12 The CSE Scale has been used in patients with CHD to evaluate correlations between CSE Scale scores and readmission to hospital,13 health status14 and additional predictors.15 It has been used in its entirety15 as well as in part.16 The maintain functioning dimension has been used more frequently than the control symptoms dimension.13,14 According to previous studies, possessing a high level of self-efficacy is associated with several beneficial outcomes during cardiac recovery that are related to a healthier lifestyle,10 self-management behaviours, psychological well-being, quality of life17 and attendance in cardiac rehabilitation programmes.18 Low cardiac self-efficacy, independent of disease severity and depression, has been shown to be related to increased symptom burden, impaired physical function and poorer overall health and quality of life in patients with CHD.14 In addition, low cardiac selfefficacy has been found to be a marker of impaired heart function and associated with readmission to hospital with symptoms similar to heart failure.13 Factors related to a person’s perception, such as employment and awareness of risk factors, rather than disease knowledge, are more likely to be associated with high cardiac self-efficacy.15 It seems to be possible to influence and reinforce selfefficacy; for instance, intervention studies aimed at improving self-efficacy in patients with cardiac diseases have found increased adherence to medications and recommended diet, improved physical activity and ability to manage stress.19 It is important to emphasise what determines whether a person will make a behavioural change is based on confidence in his/her own ability to accomplish such a
change, which is in line with the concept of self-efficacy as well as with person-centred care.7,20 The significance of self-efficacy in relation to health behaviours is important to define and evaluate, particularly during coronary prevention and rehabilitation. Further research on the role of cardiac self-efficacy is warranted, particularly in relation to person-centred care, where valid and reliable instruments also based on theoretical concepts related to such care are called for in evaluating the effects of person-centred interventions. The aim of the present study was to validate the CSE Scale, as a first step in evaluating a person-centred care intervention, by examining the internal structure of the scale using confirmatory factor analysis and test convergent and discriminant validity. The present study tested the following hypotheses: (a) the 13-item CSE Scale will represent two dimensions: control symptoms and maintain functioning; (b) the CSE Scale will be positively correlated with the General Self-Efficacy Scale (GSE Scale)8 and negatively correlated with the Fatalism scale in the General Coping Questionnaire (GCQ).21
Method Participants and procedure The study sample consisted of patients who had been hospitalised two months earlier for an acute coronary syndrome (ACS) event. ACS is an umbrella term for clinical signs and symptoms of myocardial ischemia, which comprises unstable angina pectoris, non-ST-segment elevation infarction and ST-segment elevation myocardial infarction.22 The overall sample consisted of 288 respondents ⩽75 years (72 women, 216 men; mean age 62.2) who were admitted to coronary care units (CCUs) for ACS in western Sweden. The respondents participated in two different research projects. The respondents were invited to participate during their hospital stay when they were considered as clinically stable. The first subsample (a) consisted of 140 patients (32 women, 108 men; mean age 62.8) who were included during the period March 2011–March 2012 from a CCU at a rural hospital to participate in a follow-up study concerning fatigue after myocardial infarction. The second subsample (b) consisted of 148 patients (40 women, 108 men; mean age 61.6) who were recruited during the period June 2011–May 2013 from two CCUs at a university hospital to participate in a randomised controlled trial examining the effects of person-centred care in patients with ACS. In both subsamples, patients were excluded if they had other severe diseases (e.g. advanced cancer), cognitive disability or current abuse of alcohol or drugs. Common to all respondents in both subsamples was that they had completed a package of questionnaires that was sent by post to the respondent’s homes two months after their ACS event, including the CSE Scale. Subsample (a) also answered the GCQ including the Fatalism scale, which was considered
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
3
Fors et al. Table 1. Characteristics of the study group. All n=288
Subsample (a) n=140
Subsample (b) n=148
Characteristics Myocardial infarction, n (%) Unstable angina pectoris, n (%) Gender, female, n (%) Age at inclusion (mean)
237 (82.3) 51 (17.7) 72 (25) 62.2 (±8.6)
140 (100) – 32 (22.9) 62.8 (±8)
97 (65.5) 51 (34.5) 40 (27) 61.6 (±9.2)
Highest education level Elementary school (n) High school (n) University (n)
98 105 85
68 48 24
30 57 61
Medical history Myocardial infarction (n)
53
14
39
Acute treatment at hospital Percutaneous coronary intervention (n) Coronary artery bypass grafting (n)
151 10
49 5
102 5
appropriate for testing discriminant validity.23 The Fatalism scale was chosen because we considered it theoretically probable that a person who rates high on the Fatalism scale also will rate low on the CSE Scale. Subsample (b) answered the GSE Scale, which was considered appropriate for testing convergent validity.23 The reason for choosing the GSE Scale to test convergent validity was that it is probable that a person who rates high on the general selfefficacy scale also will rate high on the CSE Scale, as they are rooted in the same concept. Patients’ characteristics are described in Table 1. Ethical approval was received from the Regional Ethical Review Board, and the participants gave their written informed consent.
Measurement Cardiac self-efficacy. The CSE Scale developed by Sullivan et al.12 consisted of 13 items, in English, in which patients were asked to rate: ‘how confident are you that you know or can…’ on a five-point Likert scale (0=not at all, 1=somewhat confident, 2=moderately confident, 3=very confident, 4=completely confident). The CSE Scale comprised two dimensions (control symptoms and maintain functioning) and demonstrated high internal consistency measured by Cronbach’s alpha (0.90 and 0.87, respectively) as well as good convergent and discriminant validity when examined in relation to outcomes from dissimilar and similar scales. The control symptoms dimension consists of eight items and the maintain functioning dimension consists of the remaining five items. In order to measure cardiac self-efficacy in a Swedish population, the CSE Scale12 was translated from English to Swedish. The forward translation into Swedish was carried out independently by two Swedish-speaking researchers within the research field. This resulted in a preliminary Swedish version of the CSE Scale based on a synthesis of these two translations. In the next step, a researcher who is a
native speaker of English performed the backward translation into English and discrepancies were resolved.24 Because treatments for patients with ACS have improved,1 resulting in patients currently experiencing fewer symptoms, a minor formulation modification was considered to be reasonable and was made for the first four items (from how confident are you that you know or can control your chest pain/breathlessness… to how confident are you that you, if you were to experience chest pain/breathlessness, can control…). Also the response alternative ‘non applicable’ was removed as all the items are considered applicable after changing the wording of the first four items and adding ‘if’. To examine convergent and discriminant validity, we used the GSE Scale8 and the Fatalism scale in the GCQ.21 General self-efficacy. The GSE Scale assesses the strength of personal beliefs in one’s ability to cope with and adapt to a number of difficult problems and challenges that are experienced in life. It consists of 10 items and responses are made on a four-point scale (1=not at all true, 2=hardly true, 3=moderately true, 4=exactly true). The items concern how one’s actions can lead to successful outcomes, e.g. achieving goals, dealing efficiently with unexpected events, handling unforeseen situations and finding solutions to problems.8 Fatalism. The Fatalism scale is one dimension in the GCQ that consists of four items with responses on a six-point scale (from ‘I always think or act like this’ to ‘I never think or act like this’). The items concern a person’s beliefs that various outcomes depend on either fate, luck or the actions of others, or that one cannot control them oneself.21
Statistical analysis The CSE Scale was completed by the present study sample of 288 respondents, and we psychometrically evaluated the
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
4
European Journal of Cardiovascular Nursing
Table 2. Goodness of fit indices for the models. Model
χ2 value
Df
RMSEA
SRMR
CFI
Three-factor model Three-factor model minus item 8 Three-factor model minus item 8 and covariance between the residuals of item 3 and 4
240.380 187.759 97.972
62 51 50
0.100 0.096 0.058
0.084 0.071 0.047
0.878 0.901 0.965
CFI: comparative fit index; Df: degrees of freedom; RMSEA: root mean square error of approximation; SRMR: standardised root mean square residual.
dimensionality of the scale using confirmatory factor analysis. The chosen rule for required sample size is based in the method literature (the number of items multiplied by 10).25 The analyses were performed with Mplus version 526 in the STREAMS27 environment. Model fit evaluation was estimated using the following tests: χ2, the comparative fit index (CFI), the standardised root mean square residual (SRMR) and the root mean square error of approximation (RMSEA). Values for CFI can range from 0–1, where values over 0.9 are indicative of an acceptable fit, and for an excellent fit CFI values should be over 0.95. A model that exhibits an acceptable fit should have a RMSEA below 0.08 to be acceptable, whereas to be good, the RMSEA should be below 0.05. The SRMR is considered to indicate a good fit if the value is below 0.08.28 Convergent and discriminant validity were tested using Pearson’s correlation coefficient. Scores for the instruments were calculated by means of sum for each dimension.
Missing data The total amount of internal missing data was 50 scores distributed across all of the items. Although the number of missing variables was very small, in order to include all of the collected information, the missing data modelling procedure implemented in the Mplus program was used.29 This procedure yields unbiased estimates under relatively moderate assumptions, which in the current study are fully satisfied.30,31
Results Initially, when a two-factor model for the CSE Scale was applied to the 288 respondents’ response data, the initial model fit was unacceptable. This meant that the first hypothesis – that the CSE Scale represents two dimensions – had to be rejected. The modification indices indicated that the first four items in the scale represented an independent dimension. This was also confirmed by face validity, as it seemed reasonable to argue that items 1–9 could be divided into two dimensions, where the first measures control symptoms and the second measures control illness. Further, based on this result, a three-factor model analysis indicated that the fit indices improved (Table 2). The standardised factor loading showed that all items were positively and significantly related to each of the three
factors. However, modification indices indicated that item 8 ‘How much physical activity is good for you’ (belonging to the second factor ‘control illness’, factor loading=0.603) was also associated with the third dimension ‘maintain functioning’ and particularly correlated with item 13 ‘Get regular aerobic exercise’ (work up a sweat and increase your heart rate). With regard to face validity, it makes sense that item 8 and item 13 could be understood in the same way by respondents and thus essentially measure the same thing. As a consequence of this, item 8 was considered unreliable and removed, resulting in an improvement of the model with acceptable levels (CFI=0.901; SRMR=0.071), but still with an unacceptable RMSEA (0.096) (Table 2). In addition, modification indices also indicated a strong covariance between the residuals of item 3 and 4, possibly due to the wording of these items, which can be explained in terms of methodological variance. To summarise, the final model was built up with one latent variable for each of the three subscales (control symptoms, control illness and maintain functioning) and with covariance between the three latent variables. Consequently, a three-factor model with item 8 excluded, which also took into account the covariance between the residuals of item 3 and 4, was tested, resulting in an excellent CFI (0.965), a good SRMR (0.047) and an acceptable (slightly above what is considered a good fit) RMSEA (0.058) (Table 2). Modification indices also noted covariance between item 1 and 2, however that only improved the model marginally. Calculation of Cronbach’s alpha for the 12 items in the CSE Scale resulted in excellent reliability (0.89). The covariances between the three factors were relatively high: 0.57 for control symptoms and control illness, 0.48 for control symptoms and maintain functioning and 0.56 for controll illness and maintain functioning. This indicated that an underlying communality represented the same construct. Hence, a higher-order model with a global factor related to the three factors was specified and tested (Figure 1). The analysis confirmed that the CSE Scale is organised hierarchically with one global dimension at the apex. This model was equally suitable as the three-factor model when considering the same preconditions, i.e. that item 8 is excluded and taking into account the covariance between the residuals of item 3 and 4 (CFI=0.965; SRMR=0.047; RMSEA=0.058). Note that statistical tests of the fit of a hypothesised second-order factor require that
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
5
Fors et al.
Figure 1. The higher-order model containing 12 of the 13 items on the Swedish version of the Cardiac Self-Efficacy Scale.
Table 3. Correlations between the dimensions in the Swedish version of the Cardiac Self-Efficacy Scale (CSE Scale) and other measured variables (convergent and discriminant validity).
Control symptoms Control illness Maintain functioning Global cardiac self-efficacy
GSE Scale correlation
Fatalism correlation
+0.450 (p=0.000) +0.285 (p=0.000) +0.513 (p=0.000) +0.602 (p=0.000)
−0.284 (p=0.001) −0.122 (p=0.156) −0.424 (p=0.000) −0.377 (p=0.000)
Fatalism: Fatalism scale in the General Coping Questionnaire; GSE Scale: General Self-Efficacy Scale.
four or more first-order factors be included in the model. That is, this model cannot be properly tested for model fit. However, the factor loadings on the global factor were generally high, control symptoms=0.70, control illness=0.81 and maintain functioning=0.69 (Figure 1). Thus, the factor loadings are generally high on both levels, which indicates that it is plausible to use a total summary score of the scale to reflect a global cardiac self-efficacy dimension.
Convergent and discriminant validity The analysis of convergent and discriminant validity confirmed the second hypothesis, that the CSE Scale was associated with external variables in expected direction. In subsample (a), the three subscales, control symptoms, control illness and maintain functioning, and the total
summary score were negatively correlated with the Fatalism scale in the GCQ. The Fatalism scale correlated most strongly with the maintain functioning dimension and the global cardiac self-efficacy dimension (Table 3). In subsample (b), the three CSE Scale dimensions, control symptoms, control illness and maintain functioning, and the scale as a global cardiac self-efficacy dimension were positively correlated with the GSE Scale. The GSE Scale correlated most strongly with the maintain functioning dimension and the global cardiac self-efficacy dimension (Table 3).
Discussion To the best of our knowledge, this is the first study to validate a Swedish version of the CSE Scale, a questionnaire
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
6
European Journal of Cardiovascular Nursing
used to measure specific self-efficacy in patients with coronary disease. The overall aim was to validate the internal structure of the scale, as a first step of evaluating a personcentred care intervention, in a sample of persons treated for ACS. The results from the confirmatory factor analysis revealed that the data comprise three dimensions. Due to the hierarchical structure with high factor loadings, a higher-order model was tested that supported summing the items to give a total summary score that measures cardiac self-efficacy. This differs from the original CSE Scale, which consists of two dimensions.12 Based on the present results, two substantial changes are suggested. The first change in the CSE Scale would be to divide the first eight items into two factors, where the first four items still represent the dimension control symptoms and the subsequent four items represent a new dimension, control illness. The second proposed change is to exclude item 8, which belongs to the dimension control illness. However, the dimension maintain functioning remains stable and is fully in line with the original version. The ability to assess three underlying dimensions as well as obtain a summary measure of cardiac self-efficacy that represents a global dimension may be beneficial in further care of patients with ACS. Because patients’ possess different levels of cardiac self-efficacy, the CSE Scale should prove to be a useful instrument in clinical practice. An interview study indicates that although it is a hazardous adventure to be affected by ACS patients’ are already prepared during hospitalisation to discuss their illness and forthcoming goals from a person-centred perspective in order to optimise their future health.32 Use of the instrument may help identify patients at risk for developing negative health outcomes as a consequence of the ACS. Integrating a person’s cardiac self-efficacy into a thorough dialogue may support person-centred care, which has been shown to have several benefits, such as shortened hospital stays33 and less uncertainty,34 in patients with chronic heart failure. The usability of the instrument at an individual clinical level is also supported by the present study’s statistical analysis given the high Cronbach’s alpha values and the generally high factor loadings. In an Asian study, cardiac self-efficacy has been shown to be an important factor in influencing health behaviours,35 which ought to be examined also among other populations. Critically, cardiac self-efficacy has been shown to be modifiable through health behaviour interventions such as exercise training programmes.36 A previous study also showed that selfefficacy is associated with attendance in cardiac rehabilitation programmes,18 and further ongoing intervention studies are trying to determine what role specific cardiac self-efficacy plays in this context.37 The analysis revealed a new factor, the control illness dimension, which covers items 5–7. When studying these items in more detail, we noted that they have a common denominator other than control symptoms, which is the
dimension they were originally associated with.12 These items are more focused on how to control illness through contact with health care professionals and taking daily medications. This is in comparison with the remaining items 1–4 in the control symptoms dimension, which are clearly linked to being able to control symptoms such as chest pain and breathlessness by adjusting activity level and taking extra medications when needed. In this context, it is also valuable to emphasise that the maintain functioning dimension demonstrated the strongest correlation with both the GSE Scale and the Fatalism scale in the GCQ. Patients’ ability to control their perceived symptoms and illness is associated with self-efficacy in relation to maintaining healthy behaviour.11 Perceived control over cardiac illness prior to an ACS event has also been found to reduce the risk of in-hospital complications.38 All correlations between the CSE Scale in relation to the GSE Scale and the Fatalism scale in the GCQ were significant, except for the correlation between the control illness dimension and the Fatalism scale in the GCQ. However, the three items in the control illness dimension showed strong factor loadings and the direction of the correlations with the GSE Scale and the Fatalism scale in the GCQ were as expected. The CSE Scale correlated negatively with the Fatalism scale in the GCQ, which was consistent with our second hypothesis. Previous studies have reported a clear association between low cardiac selfefficacy and several health complaints,14 while high fatalism has been shown to be related to a higher frequency of symptoms common in patients with ACS.21 Considering that both the CSE Scale and the GSE Scale are rooted in the same concept of self-efficacy, a positive correlation was in line with the expected outcome. One issue that needs to be discussed is whether it is justified to use a scale that measures specific cardiac self-efficacy or whether it is sufficient to simply measure general selfefficacy. According to Bandura, a person’s self-efficacy is specific to each task (e.g. physical exercise, dieting) and thus it shapes behaviours that will result in specific outcomes.39 In the present study, the observed correlation between these Scales (CSE and GSE) was clearly positive; however it was not so strong that we can assume they measure the same thing. This may indicate that it is possible for a person to possess high general self-efficacy, which concerns the ability to deal with general challenges in life, and at the same time possess low cardiac selfefficacy, which instead focuses on managing a particular cardiac illness. Previous studies have argued that selfefficacy should be considered a behaviour-specific ability that varies with tasks and challenges.19,40 The present study has some limitations. Because the study group derives from two different hospitals, rural and university, there might be a difference in the medical treatment and rehabilitation routines offered and neither gender differences were explored. The CSE Scale was validated
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
7
Fors et al. among persons who had been hospitalised two months earlier for an ACS event; therefore use of the instrument is primarily appropriate in this population. Thus it is not inconceivable that the version in its entirety could also be used for patients with a broader spectrum of cardiovascular diseases, in which case the instrument needs to be evaluated in other samples and studies. At the factor level, the maintain functioning dimension in the original CSE Scale has been found to be related to self-reported physical functioning in patients with chronic obstructive pulmonary disease and chronic heart failure.41 It would seem to be important to improve cardiac selfefficacy among patients with ACS. The CSE Scale is a self-reported questionnaire that can provide greater insight into a person’s self-efficacy belief about the illness. Thus, in healthcare practice, the CSE Scale combined with an in-depth dialogue can be used to take into account the patient’s perspective of the illness in relation to selfefficacy and formulate a personal health plan. Such a person-centred approach may help to balance standardised treatments, which are often focused on the disease from a healthcare provider perspective. This is in order to optimise health outcomes for persons affected by ACS.
Implications for practice •• The Cardiac Self-Efficacy Scale is a valid questionnaire that might be useful for evaluation of person-centred care. •• The Cardiac Self-Efficacy Scale has three dimensions, but can well be used as a total summary score measuring cardiac self-efficacy. •• Combined with a thorough dialogue the Cardiac Self-Efficacy Scale can be used as a tool to facilitate person-centred care.
Conflict of interests None declared.
Funding This work was supported by the Centre for Person-Centred Care at the University of Gothenburg (GPCC), Sweden. GPCC is funded by the Swedish Government’s grant for Strategic Research Areas, Care Sciences (Application to Swedish Research Council no. 2009-1088) and co-funded by the University of Gothenburg, Sweden. The Research and Development Unit, Primary Health Care, Region Västra Götaland also contributed to the funding of the study.
References 1. Nichols M, Townsend N, Scarborough P, et al. Cardiovascular disease in Europe: Epidemiological update. Eur Heart J 2013; 34: 3028–3034.
2. Brink E, Alsen P, Herlitz J, et al. General self-efficacy and health-related quality of life after myocardial infarction. Psychol Health Med 2012; 17: 346–355. 3. Schweikert B, Hunger M, Meisinger C, et al. Quality of life several years after myocardial infarction: Comparing the MONICA/KORA registry to the general population. Eur Heart J 2009; 30: 436–443. 4. Roest AM, Martens EJ, Denollet J, et al. Prognostic association of anxiety post myocardial infarction with mortality and new cardiac events: A meta-analysis. Psychosom Med 2010; 72: 563–569. 5. Meijer A, Conradi HJ, Bos EH, et al. Adjusted prognostic association of depression following myocardial infarction with mortality and cardiovascular events: Individual patient data meta-analysis. Br J Psychiatry 2013; 203: 90–102. 6. Bandura A. Self-efficacy: Toward a unifying theory of behavioral change. Psychol Rev 1977; 84: 191–215. 7. Ekman I, Swedberg K, Taft C, et al. Person-centered care– ready for prime time. Eur J Cardiovasc Nurs 2011; 10: 248–251. 8. Schwarzer R and Jerusalem M. Generalized Self-Efficacy scale. In: Weinman J, Wright S and Johnston M (eds) Measures in health psychology: A user’s portfolio causal and control beliefs. Windsor: NFER-Nelson, 1995, pp.35–37. 9. Luszczynska A, Scholz U and Schwarzer R. The general self-efficacy scale: multicultural validation studies. J Psychol 2005; 139: 439–457. 10. Sol BG, van der Graaf Y, van Petersen R, et al. The effect of self-efficacy on cardiovascular lifestyle. Eur J Cardiovasc Nurs 2011; 10: 180–186. 11. Lau-Walker M. Importance of illness beliefs and self efficacy for patients with coronary heart disease. J Adv Nurs 2007; 60: 187–198. 12. Sullivan MD, LaCroix AZ, Russo J, et al. Self-efficacy and self-reported functional status in coronary heart disease: a six-month prospective study. Psychosom Med 1998; 60: 473–478. 13. Sarkar U, Ali S and Whooley MA. Self-efficacy as a marker of cardiac function and predictor of heart failure hospitalization and mortality in patients with stable coronary heart disease: findings from the Heart and Soul Study. Health Psychol 2009; 28: 166–173. 14. Sarkar U, Ali S and Whooley MA. Self-efficacy and health status in patients with coronary heart disease: findings from the heart and soul study. Psychosom Med 2007; 69: 306– 312. 15. Kang Y and Yang IS. Cardiac self-efficacy and its predictors in patients with coronary artery diseases. J Clin Nurs 2013; 22: 2465–2473. 16. Lauck S, Johnson JL and Ratner PA. Self-care behaviour and factors associated with patient outcomes following same-day discharge percutaneous coronary intervention. Eur J Cardiovasc Nurs 2009; 8: 190–199. 17. Joekes K, Van Elderen T and Schreurs K. Self-efficacy and overprotection are related to quality of life, psychological well-being and self-management in cardiac patients. J Health Psychol 2007; 12: 4–16. 18. Jackson L, Leclerc J, Erskine Y, et al. Getting the most out of cardiac rehabilitation: a review of referral and adherence predictors. Heart 2005; 91: 10–14.
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
8
European Journal of Cardiovascular Nursing
19. Marks R, Allegrante JP and Lorig K. A review and synthesis of research evidence for self-efficacy-enhancing interventions for reducing chronic disability: implications for health education practice (part II). Health Promot Pract 2005; 6: 148–156. 20. Bandura A. The anatomy of stages of change. Am J Health Promot 1997; 12: 8–10. 21. Brink E, Persson LO and Karlson BW. Coping with myocardial infarction: evaluation of a coping questionnaire. Scand J Caring Sci 2009; 23: 792–800. 22. Overbaugh KJ. Acute coronary syndrome. Am J Nurs 2009; 109: 42–52; quiz 3. 23. Nunnally JC and Bernstein IH. Psychometric theory. New York: McGraw-Hill, 1994. 24. Fayers PM and Machin D. Quality of life: assessment, analysis and interpretation. Chichester: Wiley, 2000. 25. Rouquette A and Falissard B. Sample size requirements for the internal validation of psychiatric scales. Int J Methods Psychiatr Res 2011; 20: 235–249. 26. Muthén LK and Muthén BO. Mplus user`s guide. Los Angeles, California: Muthén & Muthén, 1998–2007. 27. Gustafsson J-E and Stahl PA. STREAMS user’s guide. Version 3.0 for Windows. Mölndal, Sweden: MultivariateWare, 2005. 28. Brown TA. Confirmatory factor analysis for applied research. New York: Guilford Press, 2006. 29. Muthén B, Kaplan D and Hollis M. On structural equation modeling with data that are not missing completely at random. Psychometrika 1987; 52: 431–462. 30. Allison PD. Missing data techniques for structural equation modeling. J Abnorm Psychol 2003; 112: 545–557. 31. Schafer JL and Graham JW. Missing data: Our view of the state of the art. Psychol Methods 2002; 7: 147–177.
32. Fors A, Dudas K and Ekman I. Life is lived forwards and understood backwards – experiences of being affected by acute coronary syndrome: A narrative analysis. Int J Nurs Stud 2014; 51: 430–437. 33. Ekman I, Wolf A, Olsson LE, et al. Effects of person-centred care in patients with chronic heart failure: The PCC-HF study. Eur Heart J 2012; 33: 1112–1119. 34. Dudas K, Olsson LE, Wolf A, et al. Uncertainty in illness among patients with chronic heart failure is less in personcentred care than in usual care. Eur J Cardiovasc Nurs 2013; 12: 521–528. 35. Kang Y, Yang I-S and Kim N. Correlates of health behaviors in patients with coronary artery disease. Asian Nurs Res (Korean Soc Nurs Sci) 2010; 4: 45–55. 36. Berkhuysen MA, Nieuwland W, Buunk BP, et al. Change in self-efficacy during cardiac rehabilitation and the role of perceived overprotectiveness. Patient Educ Couns 1999; 38: 21–32. 37. Herber OR, Jones MC, Smith K, et al. Assessing acute coronary syndrome patients’ cardiac-related beliefs, motivation and mood over time to predict non-attendance at cardiac rehabilitation. J Adv Nurs 2012; 68: 2778–2788. 38. McKinley S, Fien M, Riegel B, et al. Complications after acute coronary syndrome are reduced by perceived control of cardiac illness. J Adv Nurs 2012; 68: 2320–2330. 39. Bandura A. Self-efficacy: The exercise of control. Basingstoke: W. H. Freeman, 1997. 40. Clark NM and Dodge JA. Exploring self-efficacy as a predictor of disease management. Health Educ Behav 1999; 26: 72–89. 41. Arnold R, Ranchor AV, DeJongste MJ, et al. The relationship between self-efficacy and self-reported physical functioning in chronic obstructive pulmonary disease and chronic heart failure. Behav Med 2005; 31: 107–115.
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
The Cardiac Self-Efficacy Scale, a useful tool with potential to evaluate person-centred care Andreas Fors, Kerstin Ulin, Christina Cliffordson, Inger Ekman and Eva Brink Eur J Cardiovasc Nurs published online 22 August 2014 DOI: 10.1177/1474515114548622 The online version of this article can be found at: http://cnu.sagepub.com/content/early/2014/08/21/1474515114548622
Published by: http://www.sagepublications.com
On behalf of:
European Society of Cardiology
Additional services and information for European Journal of Cardiovascular Nursing can be found at: Email Alerts: http://cnu.sagepub.com/cgi/alerts Subscriptions: http://cnu.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav
>> OnlineFirst Version of Record - Aug 22, 2014 What is This?
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
548622 research-article2014
CNU0010.1177/1474515114548622European Journal of Cardiovascular Nursing 0(0)Fors et al.
EUROPEAN SOCIETY OF CARDIOLOGY ®
Original Article
The Cardiac Self-Efficacy Scale, a useful tool with potential to evaluate person-centred care
European Journal of Cardiovascular Nursing 1–8 © The European Society of Cardiology 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1474515114548622 cnu.sagepub.com
Andreas Fors1,2, Kerstin Ulin1,2, Christina Cliffordson3, Inger Ekman1,2 and Eva Brink1,2,3
Abstract Background: Cardiac self-efficacy is a person’s belief in his/her ability to manage the challenges posed by a coronary disease, and its role has been evaluated in several coronary populations using the Cardiac Self-Efficacy Scale (CSE Scale). Self-efficacy has an important role in person-centred care, however there is a lack of appropriate instruments that evaluate person-centred interventions. Aim: The purpose of this study was to validate the CSE Scale by examining its psychometric properties as a first step in evaluating a person-centred care intervention in persons with acute coronary syndrome (ACS). Methods: The study sample consisted of 288 persons (72 women, 216 men) who completed the Swedish version of the CSE Scale two months after hospitalisation for an ACS event. Construct validity was psychometrically evaluated using confirmatory factor analysis. Additionally, convergent and discriminant validity were tested using correlation analyses. Results: The results revealed that the CSE Scale was represented by three dimensions (control symptoms, control illness and maintain functioning). The analyses also showed that the CSE Scale is suitable for providing a total summary score that represents a global cardiac self-efficacy dimension. Evaluation of convergent and discriminant validity showed the expected correlations. Conclusion: The CSE Scale is a valid and reliable measure when evaluating self-efficacy in patients with ACS. It also seems to be a useful tool to promote person-centred care in clinical practice since it may offer useful guidance in the dialogue with the patient in the common creation of a personal health plan. Keywords Acute coronary syndrome, myocardial infarction, patient-centered care, person-centred care, psychometric validation, self-efficacy Date received: 3 February 2013; revised: 4 July 2014; accepted: 4 August 2014
Introduction The number of survivors of coronary heart disease (CHD) is increasing in most of the northern and western European countries.1 These survivors frequently report persistent symptoms such as fatigue,2 pain, anxiety and depression,3 which together lead to reduced quality of life.2,3 The outcome of recovery after myocardial infarction is unpredictable and dependent on several factors, such as clinical status and psychological factors e.g. anxiety4 and depression5 which are associated with adverse cardiac events and mortality.4,5 One factor that has been shown to play an important role in recovery is self-efficacy.2 The concept of self-efficacy derives from social cognitive theory and concerns people’s belief in
their ability to influence events that affect their lives.6 This approach is crucial in person-centred care, which
1Institute
of Health and Care Sciences, University of Gothenburg, Sweden 2Centre for Person-Centred Care (GPCC), University of Gothenburg, Sweden 3Department of Nursing, Health and Culture, University West, Trollhättan, Sweden Corresponding author: Andreas Fors, Institute of Health and Care Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. Email address: [email protected]
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
2
European Journal of Cardiovascular Nursing
stresses the importance of knowing the patient also as a person and addresses his/her human capacities, wishes and needs.7 General self-efficacy refers to the belief in one’s ability to respond to challenges in general, and it has also been operationalised for use in a validated8 and internationally used questionnaire.9 In addition, several attempts have been made to develop measurements targeting specific areas of self-efficacy that are associated with beneficial outcomes. For instance, a positive relationship has been reported between self-efficacy related to diabetes mellitus type 2 and adherence to physical activity and healthy food choices.10 Another study showed that patients’ initial beliefs about their illness being controllable predicted exercise self-efficacy over a three-year period.11 To examine the role of self-efficacy in addressing the challenges that arise as a result of coronary disease, regarding both function and symptom interpretation, Sullivan and co-workers developed the Cardiac Self-Efficacy Scale (CSE Scale).12 Cardiac self-efficacy refers to a person’s confidence in his/her ability to manage illness-specific outcomes. The CSE Scale consists of two dimensions: the first represents a person’s confidence that he/she can control symptoms (eight items) and the second a person’s confidence that he/she can maintain functioning (five items).12 The CSE Scale has been used in patients with CHD to evaluate correlations between CSE Scale scores and readmission to hospital,13 health status14 and additional predictors.15 It has been used in its entirety15 as well as in part.16 The maintain functioning dimension has been used more frequently than the control symptoms dimension.13,14 According to previous studies, possessing a high level of self-efficacy is associated with several beneficial outcomes during cardiac recovery that are related to a healthier lifestyle,10 self-management behaviours, psychological well-being, quality of life17 and attendance in cardiac rehabilitation programmes.18 Low cardiac self-efficacy, independent of disease severity and depression, has been shown to be related to increased symptom burden, impaired physical function and poorer overall health and quality of life in patients with CHD.14 In addition, low cardiac selfefficacy has been found to be a marker of impaired heart function and associated with readmission to hospital with symptoms similar to heart failure.13 Factors related to a person’s perception, such as employment and awareness of risk factors, rather than disease knowledge, are more likely to be associated with high cardiac self-efficacy.15 It seems to be possible to influence and reinforce selfefficacy; for instance, intervention studies aimed at improving self-efficacy in patients with cardiac diseases have found increased adherence to medications and recommended diet, improved physical activity and ability to manage stress.19 It is important to emphasise what determines whether a person will make a behavioural change is based on confidence in his/her own ability to accomplish such a
change, which is in line with the concept of self-efficacy as well as with person-centred care.7,20 The significance of self-efficacy in relation to health behaviours is important to define and evaluate, particularly during coronary prevention and rehabilitation. Further research on the role of cardiac self-efficacy is warranted, particularly in relation to person-centred care, where valid and reliable instruments also based on theoretical concepts related to such care are called for in evaluating the effects of person-centred interventions. The aim of the present study was to validate the CSE Scale, as a first step in evaluating a person-centred care intervention, by examining the internal structure of the scale using confirmatory factor analysis and test convergent and discriminant validity. The present study tested the following hypotheses: (a) the 13-item CSE Scale will represent two dimensions: control symptoms and maintain functioning; (b) the CSE Scale will be positively correlated with the General Self-Efficacy Scale (GSE Scale)8 and negatively correlated with the Fatalism scale in the General Coping Questionnaire (GCQ).21
Method Participants and procedure The study sample consisted of patients who had been hospitalised two months earlier for an acute coronary syndrome (ACS) event. ACS is an umbrella term for clinical signs and symptoms of myocardial ischemia, which comprises unstable angina pectoris, non-ST-segment elevation infarction and ST-segment elevation myocardial infarction.22 The overall sample consisted of 288 respondents ⩽75 years (72 women, 216 men; mean age 62.2) who were admitted to coronary care units (CCUs) for ACS in western Sweden. The respondents participated in two different research projects. The respondents were invited to participate during their hospital stay when they were considered as clinically stable. The first subsample (a) consisted of 140 patients (32 women, 108 men; mean age 62.8) who were included during the period March 2011–March 2012 from a CCU at a rural hospital to participate in a follow-up study concerning fatigue after myocardial infarction. The second subsample (b) consisted of 148 patients (40 women, 108 men; mean age 61.6) who were recruited during the period June 2011–May 2013 from two CCUs at a university hospital to participate in a randomised controlled trial examining the effects of person-centred care in patients with ACS. In both subsamples, patients were excluded if they had other severe diseases (e.g. advanced cancer), cognitive disability or current abuse of alcohol or drugs. Common to all respondents in both subsamples was that they had completed a package of questionnaires that was sent by post to the respondent’s homes two months after their ACS event, including the CSE Scale. Subsample (a) also answered the GCQ including the Fatalism scale, which was considered
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
3
Fors et al. Table 1. Characteristics of the study group. All n=288
Subsample (a) n=140
Subsample (b) n=148
Characteristics Myocardial infarction, n (%) Unstable angina pectoris, n (%) Gender, female, n (%) Age at inclusion (mean)
237 (82.3) 51 (17.7) 72 (25) 62.2 (±8.6)
140 (100) – 32 (22.9) 62.8 (±8)
97 (65.5) 51 (34.5) 40 (27) 61.6 (±9.2)
Highest education level Elementary school (n) High school (n) University (n)
98 105 85
68 48 24
30 57 61
Medical history Myocardial infarction (n)
53
14
39
Acute treatment at hospital Percutaneous coronary intervention (n) Coronary artery bypass grafting (n)
151 10
49 5
102 5
appropriate for testing discriminant validity.23 The Fatalism scale was chosen because we considered it theoretically probable that a person who rates high on the Fatalism scale also will rate low on the CSE Scale. Subsample (b) answered the GSE Scale, which was considered appropriate for testing convergent validity.23 The reason for choosing the GSE Scale to test convergent validity was that it is probable that a person who rates high on the general selfefficacy scale also will rate high on the CSE Scale, as they are rooted in the same concept. Patients’ characteristics are described in Table 1. Ethical approval was received from the Regional Ethical Review Board, and the participants gave their written informed consent.
Measurement Cardiac self-efficacy. The CSE Scale developed by Sullivan et al.12 consisted of 13 items, in English, in which patients were asked to rate: ‘how confident are you that you know or can…’ on a five-point Likert scale (0=not at all, 1=somewhat confident, 2=moderately confident, 3=very confident, 4=completely confident). The CSE Scale comprised two dimensions (control symptoms and maintain functioning) and demonstrated high internal consistency measured by Cronbach’s alpha (0.90 and 0.87, respectively) as well as good convergent and discriminant validity when examined in relation to outcomes from dissimilar and similar scales. The control symptoms dimension consists of eight items and the maintain functioning dimension consists of the remaining five items. In order to measure cardiac self-efficacy in a Swedish population, the CSE Scale12 was translated from English to Swedish. The forward translation into Swedish was carried out independently by two Swedish-speaking researchers within the research field. This resulted in a preliminary Swedish version of the CSE Scale based on a synthesis of these two translations. In the next step, a researcher who is a
native speaker of English performed the backward translation into English and discrepancies were resolved.24 Because treatments for patients with ACS have improved,1 resulting in patients currently experiencing fewer symptoms, a minor formulation modification was considered to be reasonable and was made for the first four items (from how confident are you that you know or can control your chest pain/breathlessness… to how confident are you that you, if you were to experience chest pain/breathlessness, can control…). Also the response alternative ‘non applicable’ was removed as all the items are considered applicable after changing the wording of the first four items and adding ‘if’. To examine convergent and discriminant validity, we used the GSE Scale8 and the Fatalism scale in the GCQ.21 General self-efficacy. The GSE Scale assesses the strength of personal beliefs in one’s ability to cope with and adapt to a number of difficult problems and challenges that are experienced in life. It consists of 10 items and responses are made on a four-point scale (1=not at all true, 2=hardly true, 3=moderately true, 4=exactly true). The items concern how one’s actions can lead to successful outcomes, e.g. achieving goals, dealing efficiently with unexpected events, handling unforeseen situations and finding solutions to problems.8 Fatalism. The Fatalism scale is one dimension in the GCQ that consists of four items with responses on a six-point scale (from ‘I always think or act like this’ to ‘I never think or act like this’). The items concern a person’s beliefs that various outcomes depend on either fate, luck or the actions of others, or that one cannot control them oneself.21
Statistical analysis The CSE Scale was completed by the present study sample of 288 respondents, and we psychometrically evaluated the
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
4
European Journal of Cardiovascular Nursing
Table 2. Goodness of fit indices for the models. Model
χ2 value
Df
RMSEA
SRMR
CFI
Three-factor model Three-factor model minus item 8 Three-factor model minus item 8 and covariance between the residuals of item 3 and 4
240.380 187.759 97.972
62 51 50
0.100 0.096 0.058
0.084 0.071 0.047
0.878 0.901 0.965
CFI: comparative fit index; Df: degrees of freedom; RMSEA: root mean square error of approximation; SRMR: standardised root mean square residual.
dimensionality of the scale using confirmatory factor analysis. The chosen rule for required sample size is based in the method literature (the number of items multiplied by 10).25 The analyses were performed with Mplus version 526 in the STREAMS27 environment. Model fit evaluation was estimated using the following tests: χ2, the comparative fit index (CFI), the standardised root mean square residual (SRMR) and the root mean square error of approximation (RMSEA). Values for CFI can range from 0–1, where values over 0.9 are indicative of an acceptable fit, and for an excellent fit CFI values should be over 0.95. A model that exhibits an acceptable fit should have a RMSEA below 0.08 to be acceptable, whereas to be good, the RMSEA should be below 0.05. The SRMR is considered to indicate a good fit if the value is below 0.08.28 Convergent and discriminant validity were tested using Pearson’s correlation coefficient. Scores for the instruments were calculated by means of sum for each dimension.
Missing data The total amount of internal missing data was 50 scores distributed across all of the items. Although the number of missing variables was very small, in order to include all of the collected information, the missing data modelling procedure implemented in the Mplus program was used.29 This procedure yields unbiased estimates under relatively moderate assumptions, which in the current study are fully satisfied.30,31
Results Initially, when a two-factor model for the CSE Scale was applied to the 288 respondents’ response data, the initial model fit was unacceptable. This meant that the first hypothesis – that the CSE Scale represents two dimensions – had to be rejected. The modification indices indicated that the first four items in the scale represented an independent dimension. This was also confirmed by face validity, as it seemed reasonable to argue that items 1–9 could be divided into two dimensions, where the first measures control symptoms and the second measures control illness. Further, based on this result, a three-factor model analysis indicated that the fit indices improved (Table 2). The standardised factor loading showed that all items were positively and significantly related to each of the three
factors. However, modification indices indicated that item 8 ‘How much physical activity is good for you’ (belonging to the second factor ‘control illness’, factor loading=0.603) was also associated with the third dimension ‘maintain functioning’ and particularly correlated with item 13 ‘Get regular aerobic exercise’ (work up a sweat and increase your heart rate). With regard to face validity, it makes sense that item 8 and item 13 could be understood in the same way by respondents and thus essentially measure the same thing. As a consequence of this, item 8 was considered unreliable and removed, resulting in an improvement of the model with acceptable levels (CFI=0.901; SRMR=0.071), but still with an unacceptable RMSEA (0.096) (Table 2). In addition, modification indices also indicated a strong covariance between the residuals of item 3 and 4, possibly due to the wording of these items, which can be explained in terms of methodological variance. To summarise, the final model was built up with one latent variable for each of the three subscales (control symptoms, control illness and maintain functioning) and with covariance between the three latent variables. Consequently, a three-factor model with item 8 excluded, which also took into account the covariance between the residuals of item 3 and 4, was tested, resulting in an excellent CFI (0.965), a good SRMR (0.047) and an acceptable (slightly above what is considered a good fit) RMSEA (0.058) (Table 2). Modification indices also noted covariance between item 1 and 2, however that only improved the model marginally. Calculation of Cronbach’s alpha for the 12 items in the CSE Scale resulted in excellent reliability (0.89). The covariances between the three factors were relatively high: 0.57 for control symptoms and control illness, 0.48 for control symptoms and maintain functioning and 0.56 for controll illness and maintain functioning. This indicated that an underlying communality represented the same construct. Hence, a higher-order model with a global factor related to the three factors was specified and tested (Figure 1). The analysis confirmed that the CSE Scale is organised hierarchically with one global dimension at the apex. This model was equally suitable as the three-factor model when considering the same preconditions, i.e. that item 8 is excluded and taking into account the covariance between the residuals of item 3 and 4 (CFI=0.965; SRMR=0.047; RMSEA=0.058). Note that statistical tests of the fit of a hypothesised second-order factor require that
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
5
Fors et al.
Figure 1. The higher-order model containing 12 of the 13 items on the Swedish version of the Cardiac Self-Efficacy Scale.
Table 3. Correlations between the dimensions in the Swedish version of the Cardiac Self-Efficacy Scale (CSE Scale) and other measured variables (convergent and discriminant validity).
Control symptoms Control illness Maintain functioning Global cardiac self-efficacy
GSE Scale correlation
Fatalism correlation
+0.450 (p=0.000) +0.285 (p=0.000) +0.513 (p=0.000) +0.602 (p=0.000)
−0.284 (p=0.001) −0.122 (p=0.156) −0.424 (p=0.000) −0.377 (p=0.000)
Fatalism: Fatalism scale in the General Coping Questionnaire; GSE Scale: General Self-Efficacy Scale.
four or more first-order factors be included in the model. That is, this model cannot be properly tested for model fit. However, the factor loadings on the global factor were generally high, control symptoms=0.70, control illness=0.81 and maintain functioning=0.69 (Figure 1). Thus, the factor loadings are generally high on both levels, which indicates that it is plausible to use a total summary score of the scale to reflect a global cardiac self-efficacy dimension.
Convergent and discriminant validity The analysis of convergent and discriminant validity confirmed the second hypothesis, that the CSE Scale was associated with external variables in expected direction. In subsample (a), the three subscales, control symptoms, control illness and maintain functioning, and the total
summary score were negatively correlated with the Fatalism scale in the GCQ. The Fatalism scale correlated most strongly with the maintain functioning dimension and the global cardiac self-efficacy dimension (Table 3). In subsample (b), the three CSE Scale dimensions, control symptoms, control illness and maintain functioning, and the scale as a global cardiac self-efficacy dimension were positively correlated with the GSE Scale. The GSE Scale correlated most strongly with the maintain functioning dimension and the global cardiac self-efficacy dimension (Table 3).
Discussion To the best of our knowledge, this is the first study to validate a Swedish version of the CSE Scale, a questionnaire
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
6
European Journal of Cardiovascular Nursing
used to measure specific self-efficacy in patients with coronary disease. The overall aim was to validate the internal structure of the scale, as a first step of evaluating a personcentred care intervention, in a sample of persons treated for ACS. The results from the confirmatory factor analysis revealed that the data comprise three dimensions. Due to the hierarchical structure with high factor loadings, a higher-order model was tested that supported summing the items to give a total summary score that measures cardiac self-efficacy. This differs from the original CSE Scale, which consists of two dimensions.12 Based on the present results, two substantial changes are suggested. The first change in the CSE Scale would be to divide the first eight items into two factors, where the first four items still represent the dimension control symptoms and the subsequent four items represent a new dimension, control illness. The second proposed change is to exclude item 8, which belongs to the dimension control illness. However, the dimension maintain functioning remains stable and is fully in line with the original version. The ability to assess three underlying dimensions as well as obtain a summary measure of cardiac self-efficacy that represents a global dimension may be beneficial in further care of patients with ACS. Because patients’ possess different levels of cardiac self-efficacy, the CSE Scale should prove to be a useful instrument in clinical practice. An interview study indicates that although it is a hazardous adventure to be affected by ACS patients’ are already prepared during hospitalisation to discuss their illness and forthcoming goals from a person-centred perspective in order to optimise their future health.32 Use of the instrument may help identify patients at risk for developing negative health outcomes as a consequence of the ACS. Integrating a person’s cardiac self-efficacy into a thorough dialogue may support person-centred care, which has been shown to have several benefits, such as shortened hospital stays33 and less uncertainty,34 in patients with chronic heart failure. The usability of the instrument at an individual clinical level is also supported by the present study’s statistical analysis given the high Cronbach’s alpha values and the generally high factor loadings. In an Asian study, cardiac self-efficacy has been shown to be an important factor in influencing health behaviours,35 which ought to be examined also among other populations. Critically, cardiac self-efficacy has been shown to be modifiable through health behaviour interventions such as exercise training programmes.36 A previous study also showed that selfefficacy is associated with attendance in cardiac rehabilitation programmes,18 and further ongoing intervention studies are trying to determine what role specific cardiac self-efficacy plays in this context.37 The analysis revealed a new factor, the control illness dimension, which covers items 5–7. When studying these items in more detail, we noted that they have a common denominator other than control symptoms, which is the
dimension they were originally associated with.12 These items are more focused on how to control illness through contact with health care professionals and taking daily medications. This is in comparison with the remaining items 1–4 in the control symptoms dimension, which are clearly linked to being able to control symptoms such as chest pain and breathlessness by adjusting activity level and taking extra medications when needed. In this context, it is also valuable to emphasise that the maintain functioning dimension demonstrated the strongest correlation with both the GSE Scale and the Fatalism scale in the GCQ. Patients’ ability to control their perceived symptoms and illness is associated with self-efficacy in relation to maintaining healthy behaviour.11 Perceived control over cardiac illness prior to an ACS event has also been found to reduce the risk of in-hospital complications.38 All correlations between the CSE Scale in relation to the GSE Scale and the Fatalism scale in the GCQ were significant, except for the correlation between the control illness dimension and the Fatalism scale in the GCQ. However, the three items in the control illness dimension showed strong factor loadings and the direction of the correlations with the GSE Scale and the Fatalism scale in the GCQ were as expected. The CSE Scale correlated negatively with the Fatalism scale in the GCQ, which was consistent with our second hypothesis. Previous studies have reported a clear association between low cardiac selfefficacy and several health complaints,14 while high fatalism has been shown to be related to a higher frequency of symptoms common in patients with ACS.21 Considering that both the CSE Scale and the GSE Scale are rooted in the same concept of self-efficacy, a positive correlation was in line with the expected outcome. One issue that needs to be discussed is whether it is justified to use a scale that measures specific cardiac self-efficacy or whether it is sufficient to simply measure general selfefficacy. According to Bandura, a person’s self-efficacy is specific to each task (e.g. physical exercise, dieting) and thus it shapes behaviours that will result in specific outcomes.39 In the present study, the observed correlation between these Scales (CSE and GSE) was clearly positive; however it was not so strong that we can assume they measure the same thing. This may indicate that it is possible for a person to possess high general self-efficacy, which concerns the ability to deal with general challenges in life, and at the same time possess low cardiac selfefficacy, which instead focuses on managing a particular cardiac illness. Previous studies have argued that selfefficacy should be considered a behaviour-specific ability that varies with tasks and challenges.19,40 The present study has some limitations. Because the study group derives from two different hospitals, rural and university, there might be a difference in the medical treatment and rehabilitation routines offered and neither gender differences were explored. The CSE Scale was validated
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
7
Fors et al. among persons who had been hospitalised two months earlier for an ACS event; therefore use of the instrument is primarily appropriate in this population. Thus it is not inconceivable that the version in its entirety could also be used for patients with a broader spectrum of cardiovascular diseases, in which case the instrument needs to be evaluated in other samples and studies. At the factor level, the maintain functioning dimension in the original CSE Scale has been found to be related to self-reported physical functioning in patients with chronic obstructive pulmonary disease and chronic heart failure.41 It would seem to be important to improve cardiac selfefficacy among patients with ACS. The CSE Scale is a self-reported questionnaire that can provide greater insight into a person’s self-efficacy belief about the illness. Thus, in healthcare practice, the CSE Scale combined with an in-depth dialogue can be used to take into account the patient’s perspective of the illness in relation to selfefficacy and formulate a personal health plan. Such a person-centred approach may help to balance standardised treatments, which are often focused on the disease from a healthcare provider perspective. This is in order to optimise health outcomes for persons affected by ACS.
Implications for practice •• The Cardiac Self-Efficacy Scale is a valid questionnaire that might be useful for evaluation of person-centred care. •• The Cardiac Self-Efficacy Scale has three dimensions, but can well be used as a total summary score measuring cardiac self-efficacy. •• Combined with a thorough dialogue the Cardiac Self-Efficacy Scale can be used as a tool to facilitate person-centred care.
Conflict of interests None declared.
Funding This work was supported by the Centre for Person-Centred Care at the University of Gothenburg (GPCC), Sweden. GPCC is funded by the Swedish Government’s grant for Strategic Research Areas, Care Sciences (Application to Swedish Research Council no. 2009-1088) and co-funded by the University of Gothenburg, Sweden. The Research and Development Unit, Primary Health Care, Region Västra Götaland also contributed to the funding of the study.
References 1. Nichols M, Townsend N, Scarborough P, et al. Cardiovascular disease in Europe: Epidemiological update. Eur Heart J 2013; 34: 3028–3034.
2. Brink E, Alsen P, Herlitz J, et al. General self-efficacy and health-related quality of life after myocardial infarction. Psychol Health Med 2012; 17: 346–355. 3. Schweikert B, Hunger M, Meisinger C, et al. Quality of life several years after myocardial infarction: Comparing the MONICA/KORA registry to the general population. Eur Heart J 2009; 30: 436–443. 4. Roest AM, Martens EJ, Denollet J, et al. Prognostic association of anxiety post myocardial infarction with mortality and new cardiac events: A meta-analysis. Psychosom Med 2010; 72: 563–569. 5. Meijer A, Conradi HJ, Bos EH, et al. Adjusted prognostic association of depression following myocardial infarction with mortality and cardiovascular events: Individual patient data meta-analysis. Br J Psychiatry 2013; 203: 90–102. 6. Bandura A. Self-efficacy: Toward a unifying theory of behavioral change. Psychol Rev 1977; 84: 191–215. 7. Ekman I, Swedberg K, Taft C, et al. Person-centered care– ready for prime time. Eur J Cardiovasc Nurs 2011; 10: 248–251. 8. Schwarzer R and Jerusalem M. Generalized Self-Efficacy scale. In: Weinman J, Wright S and Johnston M (eds) Measures in health psychology: A user’s portfolio causal and control beliefs. Windsor: NFER-Nelson, 1995, pp.35–37. 9. Luszczynska A, Scholz U and Schwarzer R. The general self-efficacy scale: multicultural validation studies. J Psychol 2005; 139: 439–457. 10. Sol BG, van der Graaf Y, van Petersen R, et al. The effect of self-efficacy on cardiovascular lifestyle. Eur J Cardiovasc Nurs 2011; 10: 180–186. 11. Lau-Walker M. Importance of illness beliefs and self efficacy for patients with coronary heart disease. J Adv Nurs 2007; 60: 187–198. 12. Sullivan MD, LaCroix AZ, Russo J, et al. Self-efficacy and self-reported functional status in coronary heart disease: a six-month prospective study. Psychosom Med 1998; 60: 473–478. 13. Sarkar U, Ali S and Whooley MA. Self-efficacy as a marker of cardiac function and predictor of heart failure hospitalization and mortality in patients with stable coronary heart disease: findings from the Heart and Soul Study. Health Psychol 2009; 28: 166–173. 14. Sarkar U, Ali S and Whooley MA. Self-efficacy and health status in patients with coronary heart disease: findings from the heart and soul study. Psychosom Med 2007; 69: 306– 312. 15. Kang Y and Yang IS. Cardiac self-efficacy and its predictors in patients with coronary artery diseases. J Clin Nurs 2013; 22: 2465–2473. 16. Lauck S, Johnson JL and Ratner PA. Self-care behaviour and factors associated with patient outcomes following same-day discharge percutaneous coronary intervention. Eur J Cardiovasc Nurs 2009; 8: 190–199. 17. Joekes K, Van Elderen T and Schreurs K. Self-efficacy and overprotection are related to quality of life, psychological well-being and self-management in cardiac patients. J Health Psychol 2007; 12: 4–16. 18. Jackson L, Leclerc J, Erskine Y, et al. Getting the most out of cardiac rehabilitation: a review of referral and adherence predictors. Heart 2005; 91: 10–14.
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
8
European Journal of Cardiovascular Nursing
19. Marks R, Allegrante JP and Lorig K. A review and synthesis of research evidence for self-efficacy-enhancing interventions for reducing chronic disability: implications for health education practice (part II). Health Promot Pract 2005; 6: 148–156. 20. Bandura A. The anatomy of stages of change. Am J Health Promot 1997; 12: 8–10. 21. Brink E, Persson LO and Karlson BW. Coping with myocardial infarction: evaluation of a coping questionnaire. Scand J Caring Sci 2009; 23: 792–800. 22. Overbaugh KJ. Acute coronary syndrome. Am J Nurs 2009; 109: 42–52; quiz 3. 23. Nunnally JC and Bernstein IH. Psychometric theory. New York: McGraw-Hill, 1994. 24. Fayers PM and Machin D. Quality of life: assessment, analysis and interpretation. Chichester: Wiley, 2000. 25. Rouquette A and Falissard B. Sample size requirements for the internal validation of psychiatric scales. Int J Methods Psychiatr Res 2011; 20: 235–249. 26. Muthén LK and Muthén BO. Mplus user`s guide. Los Angeles, California: Muthén & Muthén, 1998–2007. 27. Gustafsson J-E and Stahl PA. STREAMS user’s guide. Version 3.0 for Windows. Mölndal, Sweden: MultivariateWare, 2005. 28. Brown TA. Confirmatory factor analysis for applied research. New York: Guilford Press, 2006. 29. Muthén B, Kaplan D and Hollis M. On structural equation modeling with data that are not missing completely at random. Psychometrika 1987; 52: 431–462. 30. Allison PD. Missing data techniques for structural equation modeling. J Abnorm Psychol 2003; 112: 545–557. 31. Schafer JL and Graham JW. Missing data: Our view of the state of the art. Psychol Methods 2002; 7: 147–177.
32. Fors A, Dudas K and Ekman I. Life is lived forwards and understood backwards – experiences of being affected by acute coronary syndrome: A narrative analysis. Int J Nurs Stud 2014; 51: 430–437. 33. Ekman I, Wolf A, Olsson LE, et al. Effects of person-centred care in patients with chronic heart failure: The PCC-HF study. Eur Heart J 2012; 33: 1112–1119. 34. Dudas K, Olsson LE, Wolf A, et al. Uncertainty in illness among patients with chronic heart failure is less in personcentred care than in usual care. Eur J Cardiovasc Nurs 2013; 12: 521–528. 35. Kang Y, Yang I-S and Kim N. Correlates of health behaviors in patients with coronary artery disease. Asian Nurs Res (Korean Soc Nurs Sci) 2010; 4: 45–55. 36. Berkhuysen MA, Nieuwland W, Buunk BP, et al. Change in self-efficacy during cardiac rehabilitation and the role of perceived overprotectiveness. Patient Educ Couns 1999; 38: 21–32. 37. Herber OR, Jones MC, Smith K, et al. Assessing acute coronary syndrome patients’ cardiac-related beliefs, motivation and mood over time to predict non-attendance at cardiac rehabilitation. J Adv Nurs 2012; 68: 2778–2788. 38. McKinley S, Fien M, Riegel B, et al. Complications after acute coronary syndrome are reduced by perceived control of cardiac illness. J Adv Nurs 2012; 68: 2320–2330. 39. Bandura A. Self-efficacy: The exercise of control. Basingstoke: W. H. Freeman, 1997. 40. Clark NM and Dodge JA. Exploring self-efficacy as a predictor of disease management. Health Educ Behav 1999; 26: 72–89. 41. Arnold R, Ranchor AV, DeJongste MJ, et al. The relationship between self-efficacy and self-reported physical functioning in chronic obstructive pulmonary disease and chronic heart failure. Behav Med 2005; 31: 107–115.
Downloaded from cnu.sagepub.com at University of Newcastle on August 30, 2014
