http://informahealthcare.com/ada ISSN: 0095-2990 (print), 1097-9891 (electronic) Am J Drug Alcohol Abuse, 2014; 40(2): 131–136 ! 2014 Informa Healthcare USA, Inc. DOI: 10.3109/00952990.2013.877919
A validation study of the English version of the AlQol 9 to measure quality of life Carlos Zubaran, MD, MHM, PhD1, Elham Zolfaghari2, Katia Foresti, MD3, Jonathan Emerson, MD1, Rishi Sud, MD1, and Justin Surjadi1 1
School of Medicine, University of Western Sydney, 2School of Psychology, University of Western Sydney, and 3Department of Psychiatry, Westmead Hospital, Western Sydney Local Health District, Australia Abstract
Keywords
Background: Quality of life (QoL) is an important clinical and research outcome within the drug and alcohol abuse context. The AlQoL 9 is a specific questionnaire designed to assess health- and non-health-related consequences of alcoholism. The English version of the AlQoL 9 has not been validated using a larger sample. Objectives: The aim of this study was to assess the psychometric properties of the English version of AlQoL 9 in a sample of treatment-seeking individuals in Australia. Methods: A sample of 138 participants from inpatient and outpatient treatments facilities completed the AlQoL 9 test and the World Health Organisation Quality of Life Assessment-BREF (WHOQOL-BREF). The study’s investigative parameters included the demographic characteristics of the sample, internal structure, and convergent validity. Furthermore, correlations between the AlQoL 9 scale scores and the scores obtained from the WHOQOL-BREF test were investigated using Pearson product-moment correlation analyses. Results: The English version of the AlQoL 9 attained a significant Cronbach’s alpha of 0.825. The mean score obtained in the test was 21.92 (SD ¼ 6.79). Using Varimax rotation, the AlQoL 9 yielded one principal factor that had accounted for 37.85% of variance. Convergent validity analysis demonstrated significant correlations (p50.001) between the AlQoL 9 scores and the scores of all four dimensions of the WHOQOL-BREF questionnaire. Conclusion: The present study demonstrated that the English version of the AlQoL 9 constitutes a valid and reliable research instrument for evaluating quality of life among alcohol-dependent individuals.
Alcohol-related disorder, Australia, quality of life, questionnaires, validation studies
The field of quality of life (QoL) measurement has been evolving as a formal discipline for over 30 years characterised by a structured theoretical foundation, specific methodologies for assessment and measurement as well as diverse applications (1). The increasing recognition of QoL as a valid and independent outcome variable has led to its salience among treatment studies and health service research (2). It is used in clinical trials and in observational studies of health and disease with the aim of evaluating interventions, monitoring adverse effects of treatment and identifying the impact of the disease process itself (3). The concept of QoL has especial relevance to health given the World Health Organisation (WHO) definition that health can be conceptualized as not only the absence of disease but also the presence of a positive state of physical, mental, social and spiritual well-being (4). The conceptual boundaries of QoL transcend the dichotomy of the health-disease process, including also socio-economic, cultural factors and additional Address correspondence to: Carlos Zubaran, MD, MHM, PhD, Department of Psychiatry, Western Sydney Local Health District, PO Box 6010, Blacktown, NSW 2148, Australia. Tel: +61 (2) 9881 8888. Fax: +61 (2) 9881 8899. E-mail: [email protected]
Received 17 September 2013 Revised 16 December 2013 Accepted 16 December 2013 Published online 27 February 2014
aspects that contribute to health (5). defined QoL as a reflection of respondents’ perceptions and reactions to not only their mental and physical health, but also to nonhealth-related areas, including family, friends and work (6). A broader definition also includes life satisfaction, attainment in social and professional roles, a sense of being productive and having control over one’s destiny, as well as a satisfying perception of existence and spiritual fulfilment (7). Other definitions give salience to factors related to patient’s health status and overall functioning, including absence of symptoms, physical aptitude, emotional aspects, cognitive capacity and overall sense of life satisfaction (8). Quality of life, can therefore be seen as a subjective, multidimensional and dynamic paradigm between an individuals’ perceived and attained goals (9). Quality of life instruments have been distinguished as either generic or condition-specific tools (10), each category having its own constellation of advantages and disadvantages in relation to the purpose and objective of that which is investigated. Generic QoL instruments measure concepts that are representative of basic human values and that are relevant to everyone’s well-being and functional status (11). Generic QoL measures cover a broad spectrum of dimensions related to QoL, including physical aptitude, social relationships, mental
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History
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well-being and an overall perception of physical and general QoL, which allow for comparative evaluations of various health conditions (11,12). In contrast, condition-specific tools provide sensitive measurements of issues that are salient to a given disorder (11). This attribute can potentially allow for not only a finer understanding of the disorder process but also for more comprehensive planning and evaluation of intervention programs. Like in other areas of health, quality of life is also becoming an important clinical and research outcome variable within the drug and alcohol abuse context. The subjective aspect of QoL, especially in the field of mental health, has not only achieved importance in the measurement of therapeutic results but facilitated a gradual shift in clinical focus (12). In addition, given the usual chronic nature of substance dependence, it is important to establish a model of longitudinal monitoring which helps to improve communication between patients and healthcare professionals (13). The AlQoL 9 may be the only available specific questionnaire to assess health- and non-health-related consequences of alcoholism on individuals at present. This nine-item questionnaire, developed by Malet and colleagues (14), was conceived by condensing the French version of the SF-36 and including exclusively the areas that were ‘‘particularly pertinent to alcoholism’’ (11, p. 232). Data from the New European Alcoholism Treatment (NEAT) study, a prospective and open multicentric trial, was used to develop the AlQoL 9 (9). The authors aimed at identifying the best subscale of SF 36 to be used specifically for alcohol dependence, by selecting the smallest number of items covering non-redundant dimensions. Psychometric properties were adequate in the French sample and the number of resulting dimensions (nine) included both mental and physical components (9,14). The internal consistency of the French version of the AlQoL 9 was high, given the Cronbach’s coefficients of 0.85 and 0.71 reported for outpatients and inpatients, respectively (14). The validity of the AlQoL 9 in the original French study was adequate, as it showed ‘‘informative qualities, and [was] sensitive to most of the factors known to be involved in the quality of life of alcohol-dependent persons’’ (14, p. 186). Given that, to date, the AlQoL 9 had not been validated for use in the English language using a large sample (11), the current study was developed with the aim of assessing the psychometric properties of the English version of AlQoL 9 as used for the first time in an Australian sample. It was hypothesised that the English version of the AlQoL 9 would yield satisfactory levels of internal consistency reliability and convergent validity. These parameters were defined respectively as follows: Cronbach’s alpha 7 for all items of the scale and Pearson’s r coefficient 0.4 with p40.05 in correlations with all domains of the WHOQOL-BREF. To the authors’ knowledge, this is the first time that an English version of the AlQoL 9 has been used to test a sample of treatment-seeking individuals.
Methods Sample This study evaluated 138 adults recruited from inpatient and outpatient treatment facilities within the Western Sydney
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Local Health District catchment area, Australia, from April 2010 to December 2012. Research sites included Blacktown Hospital, Cumberland Hospital, Nepean Hospital, and the Mount Druitt Centre for Addiction Medicine, all of which are higher education training facilities within Western Sydney Local Health District. Potential participants presenting for treatment were invited to respond to the questionnaires according to simple random sampling in order to guarantee equal probability of selection. The inclusion criteria comprised (a) being above the age of 18; (b) fulfillment of the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edition) criteria for any disorder related to alcohol use; and (c) the ability to understand the aim of the study as well as the content of the questions in both questionnaires, which entailed a satisfactory command of English. Exclusion criteria comprised of presentations exclusively due to alcohol abuse and/or involuntary admission for inpatient treatment. Informed consent This study was granted approval by the Western Sydney Local Health District Human Research Ethics Committee. Prospective participants were provided with a written protocol pertaining to the study and a verbal explanation about the purpose of the study. They were also informed that participation was voluntary, confidential and anonymous. Volunteers were also informed that they could withdraw from this study at any time without any repercussion to their treatments. Research participants were then asked to sign an informed consent form prior to their inclusion in the study. Interview process Six data collectors underwent a period of training and supervision by the principal investigator prior to administering questionnaires independently. The data collectors met regularly to address any queries and ensure each were following the same procedure. The study participants completed the questionnaires under minimal guidance from the trained examiners, who followed standardised instructional procedures. Interviews took place in a suitable room at one of the research sites mentioned above. Occasionally, specific questions not considered in the initial instruction procedures were answered on a one-to-one basis. Particular care was taken with non-native English speaking participants in order to ensure a satisfactory understanding. Instruments Demographic information forms Research participants were also asked to complete forms related to demographic information including age, sex, ethnicity, highest level of educational attainment, employment status, and most frequently consumed drugs. AlQoL 9 The AlQoL 9 includes dichotomic alternatives as well as Likert-type items varying from three to six items based on parameters of intensity and frequency. The mean overall QoL
The English version of the Alqol 9
DOI: 10.3109/00952990.2013.877919
score is expressed quantitatively and without cut-off thresholds. In this study, the English version of the AlQoL 9 was used (15). AlQoL 9 scores can vary from 9 (lowest) to 41 (highest). No changes were made in the English version used in this study.
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and the scores of each dimension of the WHOQOL-BREF test were investigated via Pearson product-moment correlation analyses. All analyses were conducted with IBM SPSS StatisticsÕ software.
Results The World Health Organisation Quality Of Life Assessment-BREF (WHOQOL-BREF)
Demographic information
The WHOQOL-BREF is a questionnaire developed by the WHO as an abbreviated 26-item version of the WHOQOL100 instrument for the assessment of quality of life across various cultural settings (16). The WHOQOL-BREF is divided into four domains: Physical, Psychological, Social Relationships, and Environment. Each domain score reflects an individual’s perception of his or her quality of life in that particular area. Two additional questions examine the individual’s overall perception of (i) quality of life and (ii) health status. The WHOQOL-BREF has been validated across a wide range of languages. Statistical analysis Descriptive statistics were used to analyse demographic information. The analysis of internal consistency of the English version of the AlQoL 9 tested in Australia was determined by generating Cronbach’s alpha indices for each question of this assessment tool. The factorial analysis of the same scale was conducted by Maximum Likelihood Factor analysis with Varimax rotation. Application of the scree test was performed to identify the most meaningful factorial structure. A Chi-square goodness-of-fit test was used to confirm that the assumption of normalcy was justified. A series of correlations between the AlQoL 9 scale scores
The sample consisted of 91 males (65.9%) and 47 females (34.1%). The mean age of the sample was 42.38 years (SD ¼ 11.52), and there was no significant age difference between male and female participants. In terms of educational attainment, 48.6% had not completed secondary school, 23.2% had completed secondary school, 18.8% had completed vocational studies, and 8% had completed a university degree or higher. The majority of the sample (75.4%) was born in Australia. Reliability estimation The internal consistency (correlation of the items with the total score) of the English version of the AlQoL 9 is shown in Table 1. All nine items included in the scale attained significant Cronbach’s alpha of 0.776 or superior. The AlQoL 9 overall Cronbach’s alpha totaled 0.825. Table 2 presents the inter-item correlation matrix for the AlQoL 9, with correlations between all items. Validity evidences Internal structure The dimensionality of the nine items was analysed using maximum likelihood factor analysis. A scree plot (shown in Figure 1) revealed that one factor was the most tenable option,
Table 1. The English version of the AlQol 9 – metric properties and item reliability data (n ¼ 138).
Item
Mean
Standard deviation
Scale mean if item deleted
Scale variance if item is deleted
Corrected item – total correlation
Cronbach’s alpha if item deleted
1. 2. 3. 4. 5. 6. 7. 8. 9.
2.20 3.49 3.10 2.88 2.83 2.24 1.18 1.34 2.64
0.77 1.45 1.58 1.47 1.40 1.04 0.39 0.48 1.24
19.71 18.42 18.80 19.02 19.07 19.67 20.72 20.57 19.26
40.78 36.36 32.01 33.06 32.21 37.90 44.35 42.87 35.35
0.478 0.438 0.647 0.643 0.752 0.557 0.309 0.479 0.622
0.815 0.822 0.793 0.793 0.776 0.805 0.830 0.821 0.795
Health limits climbing stairs Had bodily pain Being very nervous Felt downhearted and blue Felt worn out General health status Accomplished less due to emotional problems Difficulty to work as a result of physical health Physical and emotional problems interfering with social life
Table 2. The inter-item correlation matrix for the AlQol 9, with correlations between all items.
Item Item Item Item Item Item Item Item Item
1 2 3 4 5 6 7 8 9
Item 1
Item 2
Item 3
Item 4
Item 5
Item 6
Item 7
Item 8
Item 9
1 0.411** 0.318** 0.264** 0.403** 0.397** 0.100 0.413** 0.286**
1 0.275** 0.205* 0.442 0.433** 0.041 0.395** 0.279**
1 0.674 0.580** 0.310** 0.244** 0.284** 0.535**
1 0.570 0.392** 0.397** 0.245** 0.529**
1 0.527** 0.273** 0.460** 0.559**
1 0.164 0.352** 0.372**
1 0.138 0.363**
1 0.305*
1
*Correlation is significant at 0.05 level (two-tailed); **Correlation is significant at 0.01 level (two-tailed).
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Figure 1. Screen test plot representing factorial analysis Eigenvalues.
given that one main factor stood up before all remaining factors levelled off. A Varimax rotation procedure was conducted, which revealed that one factor accounted for 37.85% of variance. Factor loadings were as follows: (1) ¼ 0.49; (2) 0.48; (3) ¼ 0.72; (4) ¼ 0.72; (5) ¼ 0.83; (6) ¼ 0.59; (7) ¼ 0.36; (8) ¼ 0.50; (9) ¼ 0.69. Correlations with other variables Analyses of correlation between the AlQoL 9 test scores and the scores on different dimensions of the WHOQOL-BREF Questionnaire revealed statistically significant relationships in all cases. The correlations between the AlQoL 9 and D1, D2, D3 and D4 of the WHOQOL-BREF were respectively as follows: r ¼ 0.587, p50.001; r ¼ 0.650, p50.001; r ¼ 0.496, p50.001; r ¼ 0.528, p50.001.
Discussion The concept of QoL in the area of alcohol dependence has only recently started attracting serious research attention (17). For example, it has been applied to evaluate overall level of functioning, well-being and life satisfaction in the context of alcohol abuse and dependence (18,19). The accumulating evidence indicates that the relationship between QoL and alcohol consumption is unequivocal (20), with research evidence demonstrating a curvilinear relationship between the quantity and rate of alcohol consumption and QoL (21). It has been advocated that the objective of evaluating QoL among alcohol-dependent individuals should go beyond the basic assessment of patients with regards to the presence or absence of symptoms or adverse reaction to treatment, but also to focus on how alcohol-dependent individuals experience their daily lives (22,23). However, the evaluation of QoL among those who present with alcohol abuse and dependence has been conducted mainly using generic QoL instruments (e.g. the SF-36) (24). While generic measures allow for comparative comparisons across different categories and disorders, these tools may not fully capture all the nuances related to the QoL in a specific disorder. Some studies have focused preferentially on health-related factors, which overshadows the subjective complexities of alcoholism and the personal factors that may hinder effective treatment (22).
Am J Drug Alcohol Abuse, 2014; 40(2): 131–136
In order to overcome these shortcomings, a recent generation of assessment tools has been designed to focus specifically on areas related to alcohol dependence. In contrast to general QoL measures, which are structured around domains of similar importance, QoL tools specifically designed for alcohol dependence use measurements that allow for a specific selection of life areas that are most salient to alcoholism (11,24). Examples of life areas pertinent to alcoholism include familial, social and occupational domains where the repercussions of alcohol dependence are mostly experienced (14). Given the relevancy of the need to have reliable and valid condition-specific tools for the measurement of QoL, the present study relates to the validation of the AlQoL 9 within a large English-speaking sample. Overall, it was found that this instrument was easy to administer, well accepted by most of the research participants and that the majority of the sample found it easy to complete the questionnaire. In regards to demographic information, approximately two thirds of the sample comprised of males (65.9%) indicating that the gender distribution observed in this study, on the whole, matched the prevalence rates of alcohol use disorders by gender in Australia (16). A prototypical description of this sample would be an Australian-born male in his early 40 s who has not completed secondary education, and seeking treatment for alcohol dependence and associated problems. There has been well-documented evidence that alcohol is the most commonly used and abused licit drug in Australia (25), with males showing greater consumption rates of alcohol in high-risk quantities (26). In light of the foregoing, the demographic data and alcohol use findings obtained in the current study are consistent with previous epidemiological evidence collected in Australia. The AlQoL 9 proved to have sound psychometric properties based on the statistical analysis carried out in this study in terms of factorial structure, internal consistency and reliability. Factor analysis demonstrated the unifactorial nature of the tool and this finding is consistent with results gained in the original Malet et al. (14) study. Different criteria have been proposed for establishing the number of factors to be extracted based on the magnitudes of the Eigenvalues. One criterion is to retain all factors that have Eigenvalues greater that the unity, whereas another method is to examine the scree plot and to retain factors with Eigenvalues in the sharp descent part of the plot before the Eigenvalues start to plateau (27). A factorial analysis based on the results of the scree test yields accurate results more often than the extraction method based on Eigenvalues with values greater than the unity (28). This study utilised the scree plot test and found, as in the original Malet et al. study (14), one main factor. The AlQoL 9 was also found to perform adequately in regard to other essential psychometric properties, namely, internal consistency and reliability, thereby making it a reliable instrument for the measurement of alcohol-specific quality of life. Significant intercorrelations among all items in the AlQoL 9 as demonstrated in Table 2 were also confirmed. Cortina (29) notes that ‘‘one can achieve a high internal consistency reliability estimate by having either many items or highly intercorrelated items (or some combination of the two)’’ (29). The mean inter-item correlation score of the
The English version of the Alqol 9
DOI: 10.3109/00952990.2013.877919
AlQoL 9 was 0.491, which falls within the recommended range of 0.15–0.50 (30). Furthermore, in the current study with regard to internal consistency, all nine items included in the scale attained significant Cronbach’s alpha of 0.772 or superior with an overall Cronbach’s alpha of 0.822. These results are in line with the original Malet et al. study (14) where an internal consistency of the AlQoL 9 was also noted as being high, with an observed Cronbach’s alpha of 0.85 for outpatients and 0.71 for inpatients. Given that validation studies can potentially be more prone to methodological limitations (30), a distinct advantage of the current study was the use of face-to-face interview technique which in turn made it easier to monitor and control issues related to a more valid and reliable collection of data (e.g. rapport, engagement). An additional strength of the present study can be seen in the recruitment setting. The study was conducted entirely within the public healthcare sector, which allowed for the inclusion of all prospective research participants, irrespective of private healthcare insurance cover or employment status. The results presented in the current study can be seen as providing a fairly representative analysis of the quality of life of alcohol-dependent individuals in urban areas of Australia. However, future studies may need to identify if the scale is equally appropriate for a more rural population given certain broad differences in social structure (e.g. limited access to healthcare).
Conclusion The present study investigated the factorial validity and reliability of the AlQoL 9, which is an alcohol-specific tool designed to assess quality of life among alcohol-dependent individuals, in a population sample of English-speaking individuals in Australia. The unifactorial structure of the scale was replicated in an Australian sample. Further, the internal consistency of the AlQoL 9 was satisfactory, which demonstrates that the instrument reliably investigates quality of life as measured by its items. The AlQoL 9 was well accepted by the majority of participants and questions were answered without experiencing significant difficulties, thereby adding to its utility as a sound measuring tool. The results presented here indicate that the AlQoL 9 represents a valid and reliable measurement tool for the assessment of key issues pertinent to an alcohol dependent individual’s quality of life in urban Australia.
Acknowledgements
3. 4. 5. 6. 7. 8. 9.
10. 11.
12. 13. 14. 15.
16. 17. 18. 19.
20. 21. 22.
This study was supported by grant from the NSW Health Drug and Alcohol Research Grants Program 2009/10.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
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A validation study of the English version of the AlQol 9 to measure quality of life Carlos Zubaran, MD, MHM, PhD1, Elham Zolfaghari2, Katia Foresti, MD3, Jonathan Emerson, MD1, Rishi Sud, MD1, and Justin Surjadi1 1
School of Medicine, University of Western Sydney, 2School of Psychology, University of Western Sydney, and 3Department of Psychiatry, Westmead Hospital, Western Sydney Local Health District, Australia Abstract
Keywords
Background: Quality of life (QoL) is an important clinical and research outcome within the drug and alcohol abuse context. The AlQoL 9 is a specific questionnaire designed to assess health- and non-health-related consequences of alcoholism. The English version of the AlQoL 9 has not been validated using a larger sample. Objectives: The aim of this study was to assess the psychometric properties of the English version of AlQoL 9 in a sample of treatment-seeking individuals in Australia. Methods: A sample of 138 participants from inpatient and outpatient treatments facilities completed the AlQoL 9 test and the World Health Organisation Quality of Life Assessment-BREF (WHOQOL-BREF). The study’s investigative parameters included the demographic characteristics of the sample, internal structure, and convergent validity. Furthermore, correlations between the AlQoL 9 scale scores and the scores obtained from the WHOQOL-BREF test were investigated using Pearson product-moment correlation analyses. Results: The English version of the AlQoL 9 attained a significant Cronbach’s alpha of 0.825. The mean score obtained in the test was 21.92 (SD ¼ 6.79). Using Varimax rotation, the AlQoL 9 yielded one principal factor that had accounted for 37.85% of variance. Convergent validity analysis demonstrated significant correlations (p50.001) between the AlQoL 9 scores and the scores of all four dimensions of the WHOQOL-BREF questionnaire. Conclusion: The present study demonstrated that the English version of the AlQoL 9 constitutes a valid and reliable research instrument for evaluating quality of life among alcohol-dependent individuals.
Alcohol-related disorder, Australia, quality of life, questionnaires, validation studies
The field of quality of life (QoL) measurement has been evolving as a formal discipline for over 30 years characterised by a structured theoretical foundation, specific methodologies for assessment and measurement as well as diverse applications (1). The increasing recognition of QoL as a valid and independent outcome variable has led to its salience among treatment studies and health service research (2). It is used in clinical trials and in observational studies of health and disease with the aim of evaluating interventions, monitoring adverse effects of treatment and identifying the impact of the disease process itself (3). The concept of QoL has especial relevance to health given the World Health Organisation (WHO) definition that health can be conceptualized as not only the absence of disease but also the presence of a positive state of physical, mental, social and spiritual well-being (4). The conceptual boundaries of QoL transcend the dichotomy of the health-disease process, including also socio-economic, cultural factors and additional Address correspondence to: Carlos Zubaran, MD, MHM, PhD, Department of Psychiatry, Western Sydney Local Health District, PO Box 6010, Blacktown, NSW 2148, Australia. Tel: +61 (2) 9881 8888. Fax: +61 (2) 9881 8899. E-mail: [email protected]
Received 17 September 2013 Revised 16 December 2013 Accepted 16 December 2013 Published online 27 February 2014
aspects that contribute to health (5). defined QoL as a reflection of respondents’ perceptions and reactions to not only their mental and physical health, but also to nonhealth-related areas, including family, friends and work (6). A broader definition also includes life satisfaction, attainment in social and professional roles, a sense of being productive and having control over one’s destiny, as well as a satisfying perception of existence and spiritual fulfilment (7). Other definitions give salience to factors related to patient’s health status and overall functioning, including absence of symptoms, physical aptitude, emotional aspects, cognitive capacity and overall sense of life satisfaction (8). Quality of life, can therefore be seen as a subjective, multidimensional and dynamic paradigm between an individuals’ perceived and attained goals (9). Quality of life instruments have been distinguished as either generic or condition-specific tools (10), each category having its own constellation of advantages and disadvantages in relation to the purpose and objective of that which is investigated. Generic QoL instruments measure concepts that are representative of basic human values and that are relevant to everyone’s well-being and functional status (11). Generic QoL measures cover a broad spectrum of dimensions related to QoL, including physical aptitude, social relationships, mental
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History
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well-being and an overall perception of physical and general QoL, which allow for comparative evaluations of various health conditions (11,12). In contrast, condition-specific tools provide sensitive measurements of issues that are salient to a given disorder (11). This attribute can potentially allow for not only a finer understanding of the disorder process but also for more comprehensive planning and evaluation of intervention programs. Like in other areas of health, quality of life is also becoming an important clinical and research outcome variable within the drug and alcohol abuse context. The subjective aspect of QoL, especially in the field of mental health, has not only achieved importance in the measurement of therapeutic results but facilitated a gradual shift in clinical focus (12). In addition, given the usual chronic nature of substance dependence, it is important to establish a model of longitudinal monitoring which helps to improve communication between patients and healthcare professionals (13). The AlQoL 9 may be the only available specific questionnaire to assess health- and non-health-related consequences of alcoholism on individuals at present. This nine-item questionnaire, developed by Malet and colleagues (14), was conceived by condensing the French version of the SF-36 and including exclusively the areas that were ‘‘particularly pertinent to alcoholism’’ (11, p. 232). Data from the New European Alcoholism Treatment (NEAT) study, a prospective and open multicentric trial, was used to develop the AlQoL 9 (9). The authors aimed at identifying the best subscale of SF 36 to be used specifically for alcohol dependence, by selecting the smallest number of items covering non-redundant dimensions. Psychometric properties were adequate in the French sample and the number of resulting dimensions (nine) included both mental and physical components (9,14). The internal consistency of the French version of the AlQoL 9 was high, given the Cronbach’s coefficients of 0.85 and 0.71 reported for outpatients and inpatients, respectively (14). The validity of the AlQoL 9 in the original French study was adequate, as it showed ‘‘informative qualities, and [was] sensitive to most of the factors known to be involved in the quality of life of alcohol-dependent persons’’ (14, p. 186). Given that, to date, the AlQoL 9 had not been validated for use in the English language using a large sample (11), the current study was developed with the aim of assessing the psychometric properties of the English version of AlQoL 9 as used for the first time in an Australian sample. It was hypothesised that the English version of the AlQoL 9 would yield satisfactory levels of internal consistency reliability and convergent validity. These parameters were defined respectively as follows: Cronbach’s alpha 7 for all items of the scale and Pearson’s r coefficient 0.4 with p40.05 in correlations with all domains of the WHOQOL-BREF. To the authors’ knowledge, this is the first time that an English version of the AlQoL 9 has been used to test a sample of treatment-seeking individuals.
Methods Sample This study evaluated 138 adults recruited from inpatient and outpatient treatment facilities within the Western Sydney
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Local Health District catchment area, Australia, from April 2010 to December 2012. Research sites included Blacktown Hospital, Cumberland Hospital, Nepean Hospital, and the Mount Druitt Centre for Addiction Medicine, all of which are higher education training facilities within Western Sydney Local Health District. Potential participants presenting for treatment were invited to respond to the questionnaires according to simple random sampling in order to guarantee equal probability of selection. The inclusion criteria comprised (a) being above the age of 18; (b) fulfillment of the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edition) criteria for any disorder related to alcohol use; and (c) the ability to understand the aim of the study as well as the content of the questions in both questionnaires, which entailed a satisfactory command of English. Exclusion criteria comprised of presentations exclusively due to alcohol abuse and/or involuntary admission for inpatient treatment. Informed consent This study was granted approval by the Western Sydney Local Health District Human Research Ethics Committee. Prospective participants were provided with a written protocol pertaining to the study and a verbal explanation about the purpose of the study. They were also informed that participation was voluntary, confidential and anonymous. Volunteers were also informed that they could withdraw from this study at any time without any repercussion to their treatments. Research participants were then asked to sign an informed consent form prior to their inclusion in the study. Interview process Six data collectors underwent a period of training and supervision by the principal investigator prior to administering questionnaires independently. The data collectors met regularly to address any queries and ensure each were following the same procedure. The study participants completed the questionnaires under minimal guidance from the trained examiners, who followed standardised instructional procedures. Interviews took place in a suitable room at one of the research sites mentioned above. Occasionally, specific questions not considered in the initial instruction procedures were answered on a one-to-one basis. Particular care was taken with non-native English speaking participants in order to ensure a satisfactory understanding. Instruments Demographic information forms Research participants were also asked to complete forms related to demographic information including age, sex, ethnicity, highest level of educational attainment, employment status, and most frequently consumed drugs. AlQoL 9 The AlQoL 9 includes dichotomic alternatives as well as Likert-type items varying from three to six items based on parameters of intensity and frequency. The mean overall QoL
The English version of the Alqol 9
DOI: 10.3109/00952990.2013.877919
score is expressed quantitatively and without cut-off thresholds. In this study, the English version of the AlQoL 9 was used (15). AlQoL 9 scores can vary from 9 (lowest) to 41 (highest). No changes were made in the English version used in this study.
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and the scores of each dimension of the WHOQOL-BREF test were investigated via Pearson product-moment correlation analyses. All analyses were conducted with IBM SPSS StatisticsÕ software.
Results The World Health Organisation Quality Of Life Assessment-BREF (WHOQOL-BREF)
Demographic information
The WHOQOL-BREF is a questionnaire developed by the WHO as an abbreviated 26-item version of the WHOQOL100 instrument for the assessment of quality of life across various cultural settings (16). The WHOQOL-BREF is divided into four domains: Physical, Psychological, Social Relationships, and Environment. Each domain score reflects an individual’s perception of his or her quality of life in that particular area. Two additional questions examine the individual’s overall perception of (i) quality of life and (ii) health status. The WHOQOL-BREF has been validated across a wide range of languages. Statistical analysis Descriptive statistics were used to analyse demographic information. The analysis of internal consistency of the English version of the AlQoL 9 tested in Australia was determined by generating Cronbach’s alpha indices for each question of this assessment tool. The factorial analysis of the same scale was conducted by Maximum Likelihood Factor analysis with Varimax rotation. Application of the scree test was performed to identify the most meaningful factorial structure. A Chi-square goodness-of-fit test was used to confirm that the assumption of normalcy was justified. A series of correlations between the AlQoL 9 scale scores
The sample consisted of 91 males (65.9%) and 47 females (34.1%). The mean age of the sample was 42.38 years (SD ¼ 11.52), and there was no significant age difference between male and female participants. In terms of educational attainment, 48.6% had not completed secondary school, 23.2% had completed secondary school, 18.8% had completed vocational studies, and 8% had completed a university degree or higher. The majority of the sample (75.4%) was born in Australia. Reliability estimation The internal consistency (correlation of the items with the total score) of the English version of the AlQoL 9 is shown in Table 1. All nine items included in the scale attained significant Cronbach’s alpha of 0.776 or superior. The AlQoL 9 overall Cronbach’s alpha totaled 0.825. Table 2 presents the inter-item correlation matrix for the AlQoL 9, with correlations between all items. Validity evidences Internal structure The dimensionality of the nine items was analysed using maximum likelihood factor analysis. A scree plot (shown in Figure 1) revealed that one factor was the most tenable option,
Table 1. The English version of the AlQol 9 – metric properties and item reliability data (n ¼ 138).
Item
Mean
Standard deviation
Scale mean if item deleted
Scale variance if item is deleted
Corrected item – total correlation
Cronbach’s alpha if item deleted
1. 2. 3. 4. 5. 6. 7. 8. 9.
2.20 3.49 3.10 2.88 2.83 2.24 1.18 1.34 2.64
0.77 1.45 1.58 1.47 1.40 1.04 0.39 0.48 1.24
19.71 18.42 18.80 19.02 19.07 19.67 20.72 20.57 19.26
40.78 36.36 32.01 33.06 32.21 37.90 44.35 42.87 35.35
0.478 0.438 0.647 0.643 0.752 0.557 0.309 0.479 0.622
0.815 0.822 0.793 0.793 0.776 0.805 0.830 0.821 0.795
Health limits climbing stairs Had bodily pain Being very nervous Felt downhearted and blue Felt worn out General health status Accomplished less due to emotional problems Difficulty to work as a result of physical health Physical and emotional problems interfering with social life
Table 2. The inter-item correlation matrix for the AlQol 9, with correlations between all items.
Item Item Item Item Item Item Item Item Item
1 2 3 4 5 6 7 8 9
Item 1
Item 2
Item 3
Item 4
Item 5
Item 6
Item 7
Item 8
Item 9
1 0.411** 0.318** 0.264** 0.403** 0.397** 0.100 0.413** 0.286**
1 0.275** 0.205* 0.442 0.433** 0.041 0.395** 0.279**
1 0.674 0.580** 0.310** 0.244** 0.284** 0.535**
1 0.570 0.392** 0.397** 0.245** 0.529**
1 0.527** 0.273** 0.460** 0.559**
1 0.164 0.352** 0.372**
1 0.138 0.363**
1 0.305*
1
*Correlation is significant at 0.05 level (two-tailed); **Correlation is significant at 0.01 level (two-tailed).
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Figure 1. Screen test plot representing factorial analysis Eigenvalues.
given that one main factor stood up before all remaining factors levelled off. A Varimax rotation procedure was conducted, which revealed that one factor accounted for 37.85% of variance. Factor loadings were as follows: (1) ¼ 0.49; (2) 0.48; (3) ¼ 0.72; (4) ¼ 0.72; (5) ¼ 0.83; (6) ¼ 0.59; (7) ¼ 0.36; (8) ¼ 0.50; (9) ¼ 0.69. Correlations with other variables Analyses of correlation between the AlQoL 9 test scores and the scores on different dimensions of the WHOQOL-BREF Questionnaire revealed statistically significant relationships in all cases. The correlations between the AlQoL 9 and D1, D2, D3 and D4 of the WHOQOL-BREF were respectively as follows: r ¼ 0.587, p50.001; r ¼ 0.650, p50.001; r ¼ 0.496, p50.001; r ¼ 0.528, p50.001.
Discussion The concept of QoL in the area of alcohol dependence has only recently started attracting serious research attention (17). For example, it has been applied to evaluate overall level of functioning, well-being and life satisfaction in the context of alcohol abuse and dependence (18,19). The accumulating evidence indicates that the relationship between QoL and alcohol consumption is unequivocal (20), with research evidence demonstrating a curvilinear relationship between the quantity and rate of alcohol consumption and QoL (21). It has been advocated that the objective of evaluating QoL among alcohol-dependent individuals should go beyond the basic assessment of patients with regards to the presence or absence of symptoms or adverse reaction to treatment, but also to focus on how alcohol-dependent individuals experience their daily lives (22,23). However, the evaluation of QoL among those who present with alcohol abuse and dependence has been conducted mainly using generic QoL instruments (e.g. the SF-36) (24). While generic measures allow for comparative comparisons across different categories and disorders, these tools may not fully capture all the nuances related to the QoL in a specific disorder. Some studies have focused preferentially on health-related factors, which overshadows the subjective complexities of alcoholism and the personal factors that may hinder effective treatment (22).
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In order to overcome these shortcomings, a recent generation of assessment tools has been designed to focus specifically on areas related to alcohol dependence. In contrast to general QoL measures, which are structured around domains of similar importance, QoL tools specifically designed for alcohol dependence use measurements that allow for a specific selection of life areas that are most salient to alcoholism (11,24). Examples of life areas pertinent to alcoholism include familial, social and occupational domains where the repercussions of alcohol dependence are mostly experienced (14). Given the relevancy of the need to have reliable and valid condition-specific tools for the measurement of QoL, the present study relates to the validation of the AlQoL 9 within a large English-speaking sample. Overall, it was found that this instrument was easy to administer, well accepted by most of the research participants and that the majority of the sample found it easy to complete the questionnaire. In regards to demographic information, approximately two thirds of the sample comprised of males (65.9%) indicating that the gender distribution observed in this study, on the whole, matched the prevalence rates of alcohol use disorders by gender in Australia (16). A prototypical description of this sample would be an Australian-born male in his early 40 s who has not completed secondary education, and seeking treatment for alcohol dependence and associated problems. There has been well-documented evidence that alcohol is the most commonly used and abused licit drug in Australia (25), with males showing greater consumption rates of alcohol in high-risk quantities (26). In light of the foregoing, the demographic data and alcohol use findings obtained in the current study are consistent with previous epidemiological evidence collected in Australia. The AlQoL 9 proved to have sound psychometric properties based on the statistical analysis carried out in this study in terms of factorial structure, internal consistency and reliability. Factor analysis demonstrated the unifactorial nature of the tool and this finding is consistent with results gained in the original Malet et al. (14) study. Different criteria have been proposed for establishing the number of factors to be extracted based on the magnitudes of the Eigenvalues. One criterion is to retain all factors that have Eigenvalues greater that the unity, whereas another method is to examine the scree plot and to retain factors with Eigenvalues in the sharp descent part of the plot before the Eigenvalues start to plateau (27). A factorial analysis based on the results of the scree test yields accurate results more often than the extraction method based on Eigenvalues with values greater than the unity (28). This study utilised the scree plot test and found, as in the original Malet et al. study (14), one main factor. The AlQoL 9 was also found to perform adequately in regard to other essential psychometric properties, namely, internal consistency and reliability, thereby making it a reliable instrument for the measurement of alcohol-specific quality of life. Significant intercorrelations among all items in the AlQoL 9 as demonstrated in Table 2 were also confirmed. Cortina (29) notes that ‘‘one can achieve a high internal consistency reliability estimate by having either many items or highly intercorrelated items (or some combination of the two)’’ (29). The mean inter-item correlation score of the
The English version of the Alqol 9
DOI: 10.3109/00952990.2013.877919
AlQoL 9 was 0.491, which falls within the recommended range of 0.15–0.50 (30). Furthermore, in the current study with regard to internal consistency, all nine items included in the scale attained significant Cronbach’s alpha of 0.772 or superior with an overall Cronbach’s alpha of 0.822. These results are in line with the original Malet et al. study (14) where an internal consistency of the AlQoL 9 was also noted as being high, with an observed Cronbach’s alpha of 0.85 for outpatients and 0.71 for inpatients. Given that validation studies can potentially be more prone to methodological limitations (30), a distinct advantage of the current study was the use of face-to-face interview technique which in turn made it easier to monitor and control issues related to a more valid and reliable collection of data (e.g. rapport, engagement). An additional strength of the present study can be seen in the recruitment setting. The study was conducted entirely within the public healthcare sector, which allowed for the inclusion of all prospective research participants, irrespective of private healthcare insurance cover or employment status. The results presented in the current study can be seen as providing a fairly representative analysis of the quality of life of alcohol-dependent individuals in urban areas of Australia. However, future studies may need to identify if the scale is equally appropriate for a more rural population given certain broad differences in social structure (e.g. limited access to healthcare).
Conclusion The present study investigated the factorial validity and reliability of the AlQoL 9, which is an alcohol-specific tool designed to assess quality of life among alcohol-dependent individuals, in a population sample of English-speaking individuals in Australia. The unifactorial structure of the scale was replicated in an Australian sample. Further, the internal consistency of the AlQoL 9 was satisfactory, which demonstrates that the instrument reliably investigates quality of life as measured by its items. The AlQoL 9 was well accepted by the majority of participants and questions were answered without experiencing significant difficulties, thereby adding to its utility as a sound measuring tool. The results presented here indicate that the AlQoL 9 represents a valid and reliable measurement tool for the assessment of key issues pertinent to an alcohol dependent individual’s quality of life in urban Australia.
Acknowledgements
3. 4. 5. 6. 7. 8. 9.
10. 11.
12. 13. 14. 15.
16. 17. 18. 19.
20. 21. 22.
This study was supported by grant from the NSW Health Drug and Alcohol Research Grants Program 2009/10.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
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