Clinical Nurse SpecialistA Copyright B 2015 Wolters Kluwer Health, Inc. All rights reserved.
Feature Article The Life Changes in Epilepsy Scale Development and Establishment of Content and Face Validity Wendy R. Miller, PhD, RN, CCRN n Tamilyn Bakas, PhD, RN, FAHA, FAAN n Michael T. Weaver, PhD, RN, FAAN n Janice M. Buelow, PhD, RN, FAAN n Dragos Sabau, MD Purpose/Objectives: Epilepsy is the most common chronic neurological disease in the United States. Adults with epilepsy suffer downturns in quality of life. The development of self-management interventions aimed at improving the quality of life of adults with epilepsy is hindered by the lack of a sensitive, patient-centered outcome measure. The purpose of this study was to develop the Life Changes in Epilepsy Scale (LCES); a second purpose was to establish evidence of the content and face validity of the LCES. Methods: The LCES was developed based on existing qualitative data and a theoretical framework derived from the literature; items were developed to measure perceived changes in the areas of social functioning, somatic health, and subjective well-being since epilepsy onset. Content validity indices were calculated based on evaluation of the scale by 3 experts in the field of epilepsy, whereas face validity was evaluated by 5 adults with epilepsy who were recruited from a Midwestern epilepsy clinic; qualitative data regarding the appropriateness of outcomes included in the LCES were also collected. Results: The initial version of the LCES included 41 items. Following review of the LCES by experts in which both scale- and item-content validity indices of 1.0 were achieved, the number of items was reduced to 35. All 35 items were maintained following review of the LCES by adults with epilepsy. Qualitative comments from participants supported the inclusion of outcomes measured by the LCES. Author Affiliations: Assistant Professor (Dr Miller), Department of Adult Health, School of Nursing, Indiana University, Bloomington; Professor and Chair (Dr Bakas) and Professor (Dr Weaver) of Science of Nursing Care, School of Nursing, Indiana University, Indianapolis; Vice President (Dr Buelow), Programs and Research Epilepsy Foundation of America, Landover, Maryland; Assistant Professor (Dr Sabau), Department of Neurology, School of Medicine, Indiana University, Indianapolis. Source of Funding: National Institutes of Health (KL2TR000163). The author reports no conflicts of interest. Correspondence: Wendy R. Miller, PhD, RN, CCRN, Department of Adult Health, School of Nursing, Indiana University, 1033 E 3rd St, Sycamore Hall, Room 441 Bloomington, IN 47405 ([email protected]). DOI: 10.1097/NUR.0000000000000109
Clinical Nurse Specialist
Conclusions/Implications: Results of this study provide evidence of both content and face validity of the LCES. Further psychometric testing of the scale is ongoing. In addition to being used as an outcome measure in intervention studies, the psychometrically tested LCES can serve as a valuable tool for advanced practice nurses caring for adults with epilepsy in inpatient, outpatient, and community settings. The LCES can allow for a brief assessment of ways in which patients’ lives have been affected by epilepsy, thus allowing nurses to develop targeted nursing interventions for these patients. KEY WORDS: epilepsy, quality of life, tool development, validity
E
pilepsy, often incurable, is the most common chronic neurological disease in the United States, affecting more than 3 million Americans. In the United States, 500 people are diagnosed with the condition each day. Seventy percent of new-onset epilepsy diagnoses occur in adults.1 Given epilepsy’s chronic nature, those affected by it are often charged with managing the disease for the remainder of their lives. Prior research indicates that adults with epilepsy experience marked decrements in quality of life (QoL).2,3 The development and testing of behavioral self-management interventions for adults with epilepsy are hindered by the lack of a sensitive, patient-centered outcome measure. There currently exist several epilepsy-specific QoL measures, many of them having demonstrated evidence of reliability and validity. However, these measures are not sensitive enough, as they do not measure perceived changes in QoL caused by epilepsy. That is, they are not capable of detecting life changes specifically caused by epilepsy and its associated selfmanagement. Recent patient-centered outcomes research involving persons with adult-onset epilepsy has revealed that adult-onset epilepsy causes undesired life changes, including alterations in social functioning, somatic health, and wellbeing.2,4,5 A tool that can be easily used in clinical practice to
A
www.cns-journal.com
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
95
Feature Article measure these life changes resulting from having epilepsy is needed to prioritize and guide the development of interventions for adults with epilepsy and to provide a more comprehensive and sensitive assessment of outcomes for adults with epilepsy. The purpose of this study was to develop an instrument, the Life Changes in Epilepsy Scale (LCES), designed to measure perceived life changes in adults’ lives since the onset of epilepsy. In addition, we sought to establish content and face validity of the LCES. Development and testing of the LCES are consistent with priorities established by the Centers for Disease Control and Prevention Managing Epilepsy Well Network.6 Sensitive outcome measures are needed to test the effectiveness of new and innovative epilepsy self-management and symptomrelief interventions. Not only does the LCES have the potential to serve as a sensitive outcome measure for future clinical trials, but it might also serve as an assessment tool in practice to improve the lives of those living with epilepsy. In addition, the development of this instrument aligns with the health-related QoL initiative of Healthy People 2020, a specific goal of which is to promote the development of measures to evaluate the effects of chronic illness on QoL.7
REVIEW OF LITERATURE There is ample evidence demonstrating that epilepsy is a life-altering condition. Adults with epilepsy are likely to experience unpleasant symptoms, are at high risk for psychiatric comorbidities and other chronic conditions,8 and commonly experience unemployment and negative changes in social relationships and physical functioning.2,9 Existing Quality-of-Life Measures Table 1 summarizes a critique of 6 QoL instruments that are epilepsy-specific or widely used in the population: the Medical Outcomes SF-36 Health Survey (SF-36),10 Impact of Epilepsy Scale,11 Quality of Life IndexYEpilepsy (QoLIE),12 31-item Quality of Life in Epilepsy (QoLIE-31),13 and the Patient Reported Outcomes Measurement Information System
(PROMIS) Impact of Illness Scales.14 The SF-36 is a general measure of health with evidence of reliability and validity, including in the epilepsy population. However, it is a global measure not sensitive to the context of epilepsy. Jacoby and colleagues15 administered the SF-36 to a sample of persons with epilepsy (N = 3520) to assess psychometrics in this population. Although demonstrating evidence of reliability and validity, the SF-36 had substantial ceiling effects in all subscales. These authors recommended the use of populationspecific measures when assessing the health-related QoL in those with epilepsy. Birbeck and colleagues16 administered the SF-36, as well as an epilepsy-specific measure of healthrelated QoL (QoLIE-31), to adults with epilepsy over time. The authors correlated scores from both tools with objective measures including number of seizures experienced, days of work missed, clinic visits, and complications. Scores from the epilepsy-specific measure had correlations with objective findings that were statistically significantly larger than were those from the SF-36, and epilepsy-specific measure scores were more sensitive to change in the objective measurements than were SF-36 scores.16 In addition to being too global for the epilepsy population, the SF-36 does not measure perceived changes in health. The Impact of Epilepsy Scale, although epilepsy-specific and sensitive to measuring perceived changes, lacks evidence of reliability and validity and was theoretically based. Both the QoLIE and QoLIE-31 are useful tools in assessing the healthrelated QoL in adults with epilepsy; both have evidence of reliability, validity, and a theoretical basis and are epilepsy specific.12,13 However, neither measures perceived changes in health-related QoL and thus do not remedy the gap in measurement tools for this population described earlier. The QoLIE scales render a cross-sectional view of the QoL of a person with epilepsy, making it impossible to determine how a person’s life has be changed by epilepsy. The PROMIS14 is a system of patient-reported measures for physical, mental, and social well-being. The PROMIS has demonstrated evidence of reliability and validity in a variety of chronic disease populations. This system includes 2 instruments that measure
Table 1. Critique of Existing Instruments Instrument
Epilepsy Specific
SF-36 Health Survey
Theory Based
Measures Perceived Changes
(
Impact of Epilepsy Scale
(
Quality of Life IndexYEpilepsy (QoLIE)
(
(
QoLIE-31
(
(
Evidence of Reliability and Validity (
( ( (
Patient Reported Outcomes Measurement Information System (PROMIS) Impact of Illness Negative Scale
(
(
(
PROMIS Impact of Illness Positive Scale
(
(
(
96
www.cns-journal.com
March/April 2015
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
the impact of a chronic condition (illness impact negative or positive). This system has not, however, been used in a population of those with epilepsy, and the illness impact scales lack epilepsy-specific items. Epilepsy is a complex condition and is characterized by its unique effects on those who suffer from it. Thus, an epilepsy-specific measure is needed to adequately capture life changes due to having adult-onset epilepsy. Conceptual Framework Our goal was to develop an epilepsy-specific, theory-based, and patient-centered outcome measure sensitive to life changes caused by adult-onset epilepsy. The LCES was thus developed based on a review of the epilepsy and chronic disease self-management literature and portions of Lazarus and Folkman’s17 Theory of Stress, Coping, and Adaptation. Lazarus and Folkman identify 3 adaptational outcomes that are met to some degree as an outcome of coping: social functioning, somatic health, and subjective well-being.17 Based on qualitative research with adults with epilepsy, including that in which persons with epilepsy were asked to identify self-management outcomes of importance to them,2,4 we posit that the adaptational outcomes included in Lazarus and Folkman’s17 theory are representative of patient-centered outcomes for adults with epilepsy. The Figure depicts the conceptual framework in which the LCES is housed; it is based on a combination of a review of literature, social cognitive theory,18 socioecological theory,19 our prior qualitative research, and the Theory of Stress, Coping, and Adaptation.17 As described earlier, persons with epilepsy experience symptoms (such as physical, emotional, and cognitive), which persons with epilepsy have reported cause life changes in the areas of social functioning, somatic health, and well-being.2,4 These changes are moderated by individual characteristics such as epilepsy severity, social support, demographics, and existing comorbidities and may be mediated by internal variables of self-efficacy as defined in social cognitive theory,18 disease knowledge, and multilevel thinking. Multilevel thinking refers to a person’s ability to consider multiple levels of his/her environment when making decisions and changing behaviors and is derived from the socioecological model. The interactions between all of the previously described variables occur within the context of epilepsy self-management.
METHODS Development Following a review of literature, and based on the conceptual framework, we developed original items for the LCES; each epilepsy-specific item was designed to measure life changes since onset of epilepsy in the domains of social functioning, somatic health, and well-being. All items were Clinical Nurse Specialist
FIGURE. Conceptual framework.
written at a fifth-grade reading level.20 The response format was adapted from that of the Bakas Caregiving Outcomes Scale,21 with responses measured on a 7-point scale (changed for the worst = j3 to changed for the best = +3). This response scale was chosen because it most accurately reflects Lazarus’ definition of adaptational outcomes. Developed based on Lazarus’ definition of adaptational outcomes, the Bakas Caregiving Outcomes Scale has been shown to have strong evidence of internal consistency, reliability, and content, construct, and criterion-related validity.21 Initially, 41 items were generated. Content Validity The content validity of the 41-item LCES was evaluated via review by 3 content experts. One expert had an active program of epilepsy research, one was an expert clinician specializing in treatment of epilepsy, and one had active epilepsy-focused clinical and research programs. Experts were provided with an evaluation form, on which they were asked to assign each item to a domain (social functioning, somatic health, or well-being) and to rate its relevance to adults with epilepsy on a 1- to 5-point scale, with 1 indicating not at all relevant, and 5 indicating extremely relevant. Experts were also asked to provide suggestions for changes in wording and given the option to recommend the removal of any item. Experts were also given an area in which to leave qualitative comments about the measure. Item- and scale-level content validity indices (CVIs) were calculated using Polit and Beck’s22 guidelines. Complete agreement by all experts (item- and scale-level CVIs) was desired, given there were only 3 reviewers. Thus, we sought CVIs of 1.0 at both the item and scale levels.22 On both the item and scale
A
www.cns-journal.com
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
97
Feature Article Table 2. Domains of Life Changes and Supporting Qualitative Comments
Definition17
Domain
Sample Items (Participants Indicate Perceived Change Since Epilepsy Diagnosis)
Participant Responses
Social functioning
The way(s) in which a person fulfills various roles and satisfaction with relationships; also refers to the skill set needed to maintain roles and relationships
My relationship with my friends
‘‘My social life is pretty much turned upside downI I find it real hard to maintain my friendships and also manage this.’’
Somatic health
A person’s physiological status, including symptoms
How often I have unpleasant physical symptoms
‘‘I’m having to deal with a lot of feeling tiredI fatigued and it’s keeping me from the stuff I wanna be doing.’’
Well-being
How a person feels about himself/ herself and his/her life conditions
My happiness in general
‘‘I’m just not the same person anymoreI it’s been real hard to figure out if I can be happy againI at least not until I get used to this.’’
levels, CVIs were calculated by adding reviewers’ ratings of each item, and then the entire scale, and dividing by the total number of reviewers. Face Validity To provide evidence of face validity, following institutional review board approval, 5 persons with adult-onset epilepsy recruited from a Midwestern neuroscience center were asked to evaluate the LCES after it had been evaluated for content validity. In order to be eligible, participants had to be 18 years or older, diagnosed with epilepsy at age 18 years or older, be prescribed at least 1 antiepileptic drug, speak and read English, and be cognitively intact as measured by the Six-Item Screener for cognitive impairment.23 Participants were sent a copy of the LCES via e-mail or postal mail, along with an evaluation form. On the evaluation form, participants were asked to rate the clarity and relevance of each item using a Likert scale. They were also asked to indicate whether they suggested the removal of any items. In a follow-up phone conversation with the principal investigator, participants discussed their ratings and provided qualitative feedback regarding the scale’s ability to measure perceived life changes since onset of epilepsy. In order to determine congruence between participants’ reported life changes and those being measured by the LCES, the researcher used a semistructured interview guide to ask par-
ticipants about ways in which their lives have changed since being diagnosed with epilepsy.
RESULTS Content Validity After experts’ initial review of the LCES, the scale CVI was 0.94, and 6 items had item-level CVIs of 0.67 or lower; all experts recommended removal of these 6 items. Removal was suggested because of lack of relevance and/or redundancy with other items. Removal of these 6 items rendered item- and scale-level CVIs of 1.0, resulting in a 35-item scale with evidence of content validity. Slight changes were made to the directions on the LCES, which were recommended by all reviewers. Face Validity Three women and 2 men reviewed the LCES. Their average age was 41.2 years, with a range of 34 to 61 years. Mean age at diagnosis was 32.6 years, with a range of 21 to 51 years. Mean length of time since diagnosis was 8.6 years, with a range of 1 to 17 years. Participants’ ratings for all items ranged from 4.8 to 5. Qualitative comments provided by each participant were transcribed and analyzed via content analysis. All comments were supportive of all items being maintained in the scale, whereas no comments suggested the need for additional items. As 1 participant stated, ‘‘I feel like all the
Table 3. Sample Items and Instructions From the Life Changes in Epilepsy Scale Response Scale Changed for the Worst
Sample Item
Changed for the better
1. How often I have unpleasant symptoms
j3
j2
j1
0
+1
+2
+3
2. My memory
j3
j2
j1
0
+1
+2
+3
3. My ability to travel outside my home
j3
j2
j1
0
+1
+2
+3
Instruction: For each possible change listed, circle the number indicating the degree of change you have experienced since being diagnosed with epilepsy. The numbers indicating the degree of change range from j3 (‘‘changed for the worst’’) to +3 (‘‘changed for the best’’). The number 0 means ‘‘did not change.’’
98
www.cns-journal.com
March/April 2015
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
itemsI capture what has happened to me since I was diagnosed and areas where I think my life is different. It captures my changes at work, home, with my husband and parentsI everyone. I can’t think of anything else I would add.’’ More specifically, comments supported participants having experienced life changes in the areas of social functioning, somatic health, and well-being. Comments illustrative of all items in each of the 3 domains were made by participants. Table 2 provides examples of some of these comments. Based on feedback from the 5 participants, all 35 items were maintained, and wording of some items was changed slightly to enhance clarity. Of note is that the number of items on the LCES will be significantly reduced following future psychometric testing and item analysis.
DISCUSSION The LCES is a patient-centered outcome measure designed to assess adults’ perceived life changes due to having epilepsy (see Table 3 for sample items). Evaluation of the LCES by content experts and persons with adult-onset epilepsy led to evidence of the content and face validity of a 35-item version of the tool. Qualitative comments provided by adults with epilepsy who reviewed the LCES were supportive of the experience of life changes in the domains of social functioning, somatic health, and well-being following adultonset epilepsy; this finding is congruent with findings from multiple studies involving adults with epilepsy in which participants reported decrements in QoL in the 3 domains included in the LCES.2,4 Based on current results, the LCES is a potentially useful patient-centered outcome measure for adults with epilepsy. Before the tool can be implemented, however, establishment of the psychometrical soundness of the LCES must occur. We are currently testing the psychometric properties of the LCES with a sample of 175 adults with epilepsy. Once evidence of reliability and validity of the LCES has been obtained, the tool will be used as an outcome measure in a pilot self-management intervention. Limitations Current findings are limited by a small convenience sample. Thus, results may not be generalizable beyond the participants in this sample. As discussed earlier, psychometric testing of the LCES with a large and more diverse sample is ongoing.
CONCLUSION In addition to being used as an outcome measure in intervention studies, the psychometrically tested LCES can serve as a valuable tool for advanced practice nurses caring for adults with epilepsy in inpatient, outpatient, and community settings. The LCES can allow for a brief and simple assessment of ways in which patients’ lives have been affected by Clinical Nurse Specialist
epilepsy, thus allowing nurses to develop targeted nursing interventions for these patients.
References 1. Epilepsy Foundation of America. Epilepsy Statistics. www.epilepsy .com. Accessed April 20, 2014. 2. Unger W, Buelow J. Hybrid concept analysis of self-management in adults newly diagnosed with epilepsy. Epilepsy Behav. 2009; 14:89Y95. 3. World Health Organization. Fact Sheets. www.who.int/mediacentre/ factsheets/Millfs999/en/. Accessed April 20, 2014. 4. Miller W. Patient-centered outcomes in older adults with epilepsy. Seizure. 2014;23:592Y597. 5. Miller W, Bakas T, Buelow J. Problems, needs, and useful strategies in older adults self-managing epilepsy: implications for patient education and future intervention programs. Epilepsy Behav. 2013; 5(31):25Y30. 6. Managing Epilepsy Well Network. MEW Network at a glance. http:// www.sph.emory.edu/ManagingEpilepsyWell. Accessed April 14, 2014. 7. Department of Health and Human Services. Healthy People 2020. http://www.healthypeople.gov/2020/default.aspx. Accessed April 5, 2014. 8. Babau CS, Satischandra P, Sinha S, Subbakrishna DK. Co-morbidities in people living with epilepsy: hospital based case-control study from a resource-poor setting. Epilepsy Res. 2009;86(2): 146Y152. 9. de Boer HM. Overview and perspectives of employment in people with epilepsy. Epilepsia. 2005;46(1):52Y54. 10. Ware JEJ, Snow KK, Kosinski M, Gandek B. SF-35 Health Survey, Manual, and Interpretation Guide. Boston, MA: The Health Institute, New England Medical Center; 1993. 11. Jacoby A, Baker G, Smith D, Dewey M, Chadwick D. Measuring the impact of epilepsy: the development of a novel scale. Epilepsy Res. 1993;16(1):83Y88. 12. Ferrans C, Cohen F. Quality of life: persons with epilepsy and the general population. Epilepsia. 1996;34(6):25. 13. Cramer JA, Perrine K, Devinsky O. Bryant
Feature Article The Life Changes in Epilepsy Scale Development and Establishment of Content and Face Validity Wendy R. Miller, PhD, RN, CCRN n Tamilyn Bakas, PhD, RN, FAHA, FAAN n Michael T. Weaver, PhD, RN, FAAN n Janice M. Buelow, PhD, RN, FAAN n Dragos Sabau, MD Purpose/Objectives: Epilepsy is the most common chronic neurological disease in the United States. Adults with epilepsy suffer downturns in quality of life. The development of self-management interventions aimed at improving the quality of life of adults with epilepsy is hindered by the lack of a sensitive, patient-centered outcome measure. The purpose of this study was to develop the Life Changes in Epilepsy Scale (LCES); a second purpose was to establish evidence of the content and face validity of the LCES. Methods: The LCES was developed based on existing qualitative data and a theoretical framework derived from the literature; items were developed to measure perceived changes in the areas of social functioning, somatic health, and subjective well-being since epilepsy onset. Content validity indices were calculated based on evaluation of the scale by 3 experts in the field of epilepsy, whereas face validity was evaluated by 5 adults with epilepsy who were recruited from a Midwestern epilepsy clinic; qualitative data regarding the appropriateness of outcomes included in the LCES were also collected. Results: The initial version of the LCES included 41 items. Following review of the LCES by experts in which both scale- and item-content validity indices of 1.0 were achieved, the number of items was reduced to 35. All 35 items were maintained following review of the LCES by adults with epilepsy. Qualitative comments from participants supported the inclusion of outcomes measured by the LCES. Author Affiliations: Assistant Professor (Dr Miller), Department of Adult Health, School of Nursing, Indiana University, Bloomington; Professor and Chair (Dr Bakas) and Professor (Dr Weaver) of Science of Nursing Care, School of Nursing, Indiana University, Indianapolis; Vice President (Dr Buelow), Programs and Research Epilepsy Foundation of America, Landover, Maryland; Assistant Professor (Dr Sabau), Department of Neurology, School of Medicine, Indiana University, Indianapolis. Source of Funding: National Institutes of Health (KL2TR000163). The author reports no conflicts of interest. Correspondence: Wendy R. Miller, PhD, RN, CCRN, Department of Adult Health, School of Nursing, Indiana University, 1033 E 3rd St, Sycamore Hall, Room 441 Bloomington, IN 47405 ([email protected]). DOI: 10.1097/NUR.0000000000000109
Clinical Nurse Specialist
Conclusions/Implications: Results of this study provide evidence of both content and face validity of the LCES. Further psychometric testing of the scale is ongoing. In addition to being used as an outcome measure in intervention studies, the psychometrically tested LCES can serve as a valuable tool for advanced practice nurses caring for adults with epilepsy in inpatient, outpatient, and community settings. The LCES can allow for a brief assessment of ways in which patients’ lives have been affected by epilepsy, thus allowing nurses to develop targeted nursing interventions for these patients. KEY WORDS: epilepsy, quality of life, tool development, validity
E
pilepsy, often incurable, is the most common chronic neurological disease in the United States, affecting more than 3 million Americans. In the United States, 500 people are diagnosed with the condition each day. Seventy percent of new-onset epilepsy diagnoses occur in adults.1 Given epilepsy’s chronic nature, those affected by it are often charged with managing the disease for the remainder of their lives. Prior research indicates that adults with epilepsy experience marked decrements in quality of life (QoL).2,3 The development and testing of behavioral self-management interventions for adults with epilepsy are hindered by the lack of a sensitive, patient-centered outcome measure. There currently exist several epilepsy-specific QoL measures, many of them having demonstrated evidence of reliability and validity. However, these measures are not sensitive enough, as they do not measure perceived changes in QoL caused by epilepsy. That is, they are not capable of detecting life changes specifically caused by epilepsy and its associated selfmanagement. Recent patient-centered outcomes research involving persons with adult-onset epilepsy has revealed that adult-onset epilepsy causes undesired life changes, including alterations in social functioning, somatic health, and wellbeing.2,4,5 A tool that can be easily used in clinical practice to
A
www.cns-journal.com
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
95
Feature Article measure these life changes resulting from having epilepsy is needed to prioritize and guide the development of interventions for adults with epilepsy and to provide a more comprehensive and sensitive assessment of outcomes for adults with epilepsy. The purpose of this study was to develop an instrument, the Life Changes in Epilepsy Scale (LCES), designed to measure perceived life changes in adults’ lives since the onset of epilepsy. In addition, we sought to establish content and face validity of the LCES. Development and testing of the LCES are consistent with priorities established by the Centers for Disease Control and Prevention Managing Epilepsy Well Network.6 Sensitive outcome measures are needed to test the effectiveness of new and innovative epilepsy self-management and symptomrelief interventions. Not only does the LCES have the potential to serve as a sensitive outcome measure for future clinical trials, but it might also serve as an assessment tool in practice to improve the lives of those living with epilepsy. In addition, the development of this instrument aligns with the health-related QoL initiative of Healthy People 2020, a specific goal of which is to promote the development of measures to evaluate the effects of chronic illness on QoL.7
REVIEW OF LITERATURE There is ample evidence demonstrating that epilepsy is a life-altering condition. Adults with epilepsy are likely to experience unpleasant symptoms, are at high risk for psychiatric comorbidities and other chronic conditions,8 and commonly experience unemployment and negative changes in social relationships and physical functioning.2,9 Existing Quality-of-Life Measures Table 1 summarizes a critique of 6 QoL instruments that are epilepsy-specific or widely used in the population: the Medical Outcomes SF-36 Health Survey (SF-36),10 Impact of Epilepsy Scale,11 Quality of Life IndexYEpilepsy (QoLIE),12 31-item Quality of Life in Epilepsy (QoLIE-31),13 and the Patient Reported Outcomes Measurement Information System
(PROMIS) Impact of Illness Scales.14 The SF-36 is a general measure of health with evidence of reliability and validity, including in the epilepsy population. However, it is a global measure not sensitive to the context of epilepsy. Jacoby and colleagues15 administered the SF-36 to a sample of persons with epilepsy (N = 3520) to assess psychometrics in this population. Although demonstrating evidence of reliability and validity, the SF-36 had substantial ceiling effects in all subscales. These authors recommended the use of populationspecific measures when assessing the health-related QoL in those with epilepsy. Birbeck and colleagues16 administered the SF-36, as well as an epilepsy-specific measure of healthrelated QoL (QoLIE-31), to adults with epilepsy over time. The authors correlated scores from both tools with objective measures including number of seizures experienced, days of work missed, clinic visits, and complications. Scores from the epilepsy-specific measure had correlations with objective findings that were statistically significantly larger than were those from the SF-36, and epilepsy-specific measure scores were more sensitive to change in the objective measurements than were SF-36 scores.16 In addition to being too global for the epilepsy population, the SF-36 does not measure perceived changes in health. The Impact of Epilepsy Scale, although epilepsy-specific and sensitive to measuring perceived changes, lacks evidence of reliability and validity and was theoretically based. Both the QoLIE and QoLIE-31 are useful tools in assessing the healthrelated QoL in adults with epilepsy; both have evidence of reliability, validity, and a theoretical basis and are epilepsy specific.12,13 However, neither measures perceived changes in health-related QoL and thus do not remedy the gap in measurement tools for this population described earlier. The QoLIE scales render a cross-sectional view of the QoL of a person with epilepsy, making it impossible to determine how a person’s life has be changed by epilepsy. The PROMIS14 is a system of patient-reported measures for physical, mental, and social well-being. The PROMIS has demonstrated evidence of reliability and validity in a variety of chronic disease populations. This system includes 2 instruments that measure
Table 1. Critique of Existing Instruments Instrument
Epilepsy Specific
SF-36 Health Survey
Theory Based
Measures Perceived Changes
(
Impact of Epilepsy Scale
(
Quality of Life IndexYEpilepsy (QoLIE)
(
(
QoLIE-31
(
(
Evidence of Reliability and Validity (
( ( (
Patient Reported Outcomes Measurement Information System (PROMIS) Impact of Illness Negative Scale
(
(
(
PROMIS Impact of Illness Positive Scale
(
(
(
96
www.cns-journal.com
March/April 2015
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
the impact of a chronic condition (illness impact negative or positive). This system has not, however, been used in a population of those with epilepsy, and the illness impact scales lack epilepsy-specific items. Epilepsy is a complex condition and is characterized by its unique effects on those who suffer from it. Thus, an epilepsy-specific measure is needed to adequately capture life changes due to having adult-onset epilepsy. Conceptual Framework Our goal was to develop an epilepsy-specific, theory-based, and patient-centered outcome measure sensitive to life changes caused by adult-onset epilepsy. The LCES was thus developed based on a review of the epilepsy and chronic disease self-management literature and portions of Lazarus and Folkman’s17 Theory of Stress, Coping, and Adaptation. Lazarus and Folkman identify 3 adaptational outcomes that are met to some degree as an outcome of coping: social functioning, somatic health, and subjective well-being.17 Based on qualitative research with adults with epilepsy, including that in which persons with epilepsy were asked to identify self-management outcomes of importance to them,2,4 we posit that the adaptational outcomes included in Lazarus and Folkman’s17 theory are representative of patient-centered outcomes for adults with epilepsy. The Figure depicts the conceptual framework in which the LCES is housed; it is based on a combination of a review of literature, social cognitive theory,18 socioecological theory,19 our prior qualitative research, and the Theory of Stress, Coping, and Adaptation.17 As described earlier, persons with epilepsy experience symptoms (such as physical, emotional, and cognitive), which persons with epilepsy have reported cause life changes in the areas of social functioning, somatic health, and well-being.2,4 These changes are moderated by individual characteristics such as epilepsy severity, social support, demographics, and existing comorbidities and may be mediated by internal variables of self-efficacy as defined in social cognitive theory,18 disease knowledge, and multilevel thinking. Multilevel thinking refers to a person’s ability to consider multiple levels of his/her environment when making decisions and changing behaviors and is derived from the socioecological model. The interactions between all of the previously described variables occur within the context of epilepsy self-management.
METHODS Development Following a review of literature, and based on the conceptual framework, we developed original items for the LCES; each epilepsy-specific item was designed to measure life changes since onset of epilepsy in the domains of social functioning, somatic health, and well-being. All items were Clinical Nurse Specialist
FIGURE. Conceptual framework.
written at a fifth-grade reading level.20 The response format was adapted from that of the Bakas Caregiving Outcomes Scale,21 with responses measured on a 7-point scale (changed for the worst = j3 to changed for the best = +3). This response scale was chosen because it most accurately reflects Lazarus’ definition of adaptational outcomes. Developed based on Lazarus’ definition of adaptational outcomes, the Bakas Caregiving Outcomes Scale has been shown to have strong evidence of internal consistency, reliability, and content, construct, and criterion-related validity.21 Initially, 41 items were generated. Content Validity The content validity of the 41-item LCES was evaluated via review by 3 content experts. One expert had an active program of epilepsy research, one was an expert clinician specializing in treatment of epilepsy, and one had active epilepsy-focused clinical and research programs. Experts were provided with an evaluation form, on which they were asked to assign each item to a domain (social functioning, somatic health, or well-being) and to rate its relevance to adults with epilepsy on a 1- to 5-point scale, with 1 indicating not at all relevant, and 5 indicating extremely relevant. Experts were also asked to provide suggestions for changes in wording and given the option to recommend the removal of any item. Experts were also given an area in which to leave qualitative comments about the measure. Item- and scale-level content validity indices (CVIs) were calculated using Polit and Beck’s22 guidelines. Complete agreement by all experts (item- and scale-level CVIs) was desired, given there were only 3 reviewers. Thus, we sought CVIs of 1.0 at both the item and scale levels.22 On both the item and scale
A
www.cns-journal.com
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
97
Feature Article Table 2. Domains of Life Changes and Supporting Qualitative Comments
Definition17
Domain
Sample Items (Participants Indicate Perceived Change Since Epilepsy Diagnosis)
Participant Responses
Social functioning
The way(s) in which a person fulfills various roles and satisfaction with relationships; also refers to the skill set needed to maintain roles and relationships
My relationship with my friends
‘‘My social life is pretty much turned upside downI I find it real hard to maintain my friendships and also manage this.’’
Somatic health
A person’s physiological status, including symptoms
How often I have unpleasant physical symptoms
‘‘I’m having to deal with a lot of feeling tiredI fatigued and it’s keeping me from the stuff I wanna be doing.’’
Well-being
How a person feels about himself/ herself and his/her life conditions
My happiness in general
‘‘I’m just not the same person anymoreI it’s been real hard to figure out if I can be happy againI at least not until I get used to this.’’
levels, CVIs were calculated by adding reviewers’ ratings of each item, and then the entire scale, and dividing by the total number of reviewers. Face Validity To provide evidence of face validity, following institutional review board approval, 5 persons with adult-onset epilepsy recruited from a Midwestern neuroscience center were asked to evaluate the LCES after it had been evaluated for content validity. In order to be eligible, participants had to be 18 years or older, diagnosed with epilepsy at age 18 years or older, be prescribed at least 1 antiepileptic drug, speak and read English, and be cognitively intact as measured by the Six-Item Screener for cognitive impairment.23 Participants were sent a copy of the LCES via e-mail or postal mail, along with an evaluation form. On the evaluation form, participants were asked to rate the clarity and relevance of each item using a Likert scale. They were also asked to indicate whether they suggested the removal of any items. In a follow-up phone conversation with the principal investigator, participants discussed their ratings and provided qualitative feedback regarding the scale’s ability to measure perceived life changes since onset of epilepsy. In order to determine congruence between participants’ reported life changes and those being measured by the LCES, the researcher used a semistructured interview guide to ask par-
ticipants about ways in which their lives have changed since being diagnosed with epilepsy.
RESULTS Content Validity After experts’ initial review of the LCES, the scale CVI was 0.94, and 6 items had item-level CVIs of 0.67 or lower; all experts recommended removal of these 6 items. Removal was suggested because of lack of relevance and/or redundancy with other items. Removal of these 6 items rendered item- and scale-level CVIs of 1.0, resulting in a 35-item scale with evidence of content validity. Slight changes were made to the directions on the LCES, which were recommended by all reviewers. Face Validity Three women and 2 men reviewed the LCES. Their average age was 41.2 years, with a range of 34 to 61 years. Mean age at diagnosis was 32.6 years, with a range of 21 to 51 years. Mean length of time since diagnosis was 8.6 years, with a range of 1 to 17 years. Participants’ ratings for all items ranged from 4.8 to 5. Qualitative comments provided by each participant were transcribed and analyzed via content analysis. All comments were supportive of all items being maintained in the scale, whereas no comments suggested the need for additional items. As 1 participant stated, ‘‘I feel like all the
Table 3. Sample Items and Instructions From the Life Changes in Epilepsy Scale Response Scale Changed for the Worst
Sample Item
Changed for the better
1. How often I have unpleasant symptoms
j3
j2
j1
0
+1
+2
+3
2. My memory
j3
j2
j1
0
+1
+2
+3
3. My ability to travel outside my home
j3
j2
j1
0
+1
+2
+3
Instruction: For each possible change listed, circle the number indicating the degree of change you have experienced since being diagnosed with epilepsy. The numbers indicating the degree of change range from j3 (‘‘changed for the worst’’) to +3 (‘‘changed for the best’’). The number 0 means ‘‘did not change.’’
98
www.cns-journal.com
March/April 2015
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
itemsI capture what has happened to me since I was diagnosed and areas where I think my life is different. It captures my changes at work, home, with my husband and parentsI everyone. I can’t think of anything else I would add.’’ More specifically, comments supported participants having experienced life changes in the areas of social functioning, somatic health, and well-being. Comments illustrative of all items in each of the 3 domains were made by participants. Table 2 provides examples of some of these comments. Based on feedback from the 5 participants, all 35 items were maintained, and wording of some items was changed slightly to enhance clarity. Of note is that the number of items on the LCES will be significantly reduced following future psychometric testing and item analysis.
DISCUSSION The LCES is a patient-centered outcome measure designed to assess adults’ perceived life changes due to having epilepsy (see Table 3 for sample items). Evaluation of the LCES by content experts and persons with adult-onset epilepsy led to evidence of the content and face validity of a 35-item version of the tool. Qualitative comments provided by adults with epilepsy who reviewed the LCES were supportive of the experience of life changes in the domains of social functioning, somatic health, and well-being following adultonset epilepsy; this finding is congruent with findings from multiple studies involving adults with epilepsy in which participants reported decrements in QoL in the 3 domains included in the LCES.2,4 Based on current results, the LCES is a potentially useful patient-centered outcome measure for adults with epilepsy. Before the tool can be implemented, however, establishment of the psychometrical soundness of the LCES must occur. We are currently testing the psychometric properties of the LCES with a sample of 175 adults with epilepsy. Once evidence of reliability and validity of the LCES has been obtained, the tool will be used as an outcome measure in a pilot self-management intervention. Limitations Current findings are limited by a small convenience sample. Thus, results may not be generalizable beyond the participants in this sample. As discussed earlier, psychometric testing of the LCES with a large and more diverse sample is ongoing.
CONCLUSION In addition to being used as an outcome measure in intervention studies, the psychometrically tested LCES can serve as a valuable tool for advanced practice nurses caring for adults with epilepsy in inpatient, outpatient, and community settings. The LCES can allow for a brief and simple assessment of ways in which patients’ lives have been affected by Clinical Nurse Specialist
epilepsy, thus allowing nurses to develop targeted nursing interventions for these patients.
References 1. Epilepsy Foundation of America. Epilepsy Statistics. www.epilepsy .com. Accessed April 20, 2014. 2. Unger W, Buelow J. Hybrid concept analysis of self-management in adults newly diagnosed with epilepsy. Epilepsy Behav. 2009; 14:89Y95. 3. World Health Organization. Fact Sheets. www.who.int/mediacentre/ factsheets/Millfs999/en/. Accessed April 20, 2014. 4. Miller W. Patient-centered outcomes in older adults with epilepsy. Seizure. 2014;23:592Y597. 5. Miller W, Bakas T, Buelow J. Problems, needs, and useful strategies in older adults self-managing epilepsy: implications for patient education and future intervention programs. Epilepsy Behav. 2013; 5(31):25Y30. 6. Managing Epilepsy Well Network. MEW Network at a glance. http:// www.sph.emory.edu/ManagingEpilepsyWell. Accessed April 14, 2014. 7. Department of Health and Human Services. Healthy People 2020. http://www.healthypeople.gov/2020/default.aspx. Accessed April 5, 2014. 8. Babau CS, Satischandra P, Sinha S, Subbakrishna DK. Co-morbidities in people living with epilepsy: hospital based case-control study from a resource-poor setting. Epilepsy Res. 2009;86(2): 146Y152. 9. de Boer HM. Overview and perspectives of employment in people with epilepsy. Epilepsia. 2005;46(1):52Y54. 10. Ware JEJ, Snow KK, Kosinski M, Gandek B. SF-35 Health Survey, Manual, and Interpretation Guide. Boston, MA: The Health Institute, New England Medical Center; 1993. 11. Jacoby A, Baker G, Smith D, Dewey M, Chadwick D. Measuring the impact of epilepsy: the development of a novel scale. Epilepsy Res. 1993;16(1):83Y88. 12. Ferrans C, Cohen F. Quality of life: persons with epilepsy and the general population. Epilepsia. 1996;34(6):25. 13. Cramer JA, Perrine K, Devinsky O. Bryant
