New Quality-of-Life Inventory for Epilepsy Patients: Interim Results

Summary: The process for developing and evaluating a comprehensive, self-report measure of quality of life in epilepsy (QOLIE) is described, and interim results for 64 patients are reported. A test battery of 98 quality-of-life items was constructed with use of the RAND 36-Item Health Survey as a generic core and adding other quality-of-life items, the latter derived from a literature review and expert opinion on areas of importance to people with mild to moderate epilepsy. Seventeen scales tapping unique quality-of-life dimensions were identified from this QOLIE test battery. The battery was administered to 64 adults with mild to moderate epilepsy and their proxies (relative or close friend) on two separate visits 2–3 weeks apart. Patients also completed a neuropsychological test battery on the first visit. Interim analysis of these data demonstrated that 16 of 17 scales on the QOLIE test battery are sufficiently reliable for group comparison: Cronbach's alpha for the 16 scales ranged from 0.73 to 0.88; test-retest reliability ranged from 0.56 to 0.88. Preliminary evaluation of validity confirmed hypothesized correlations between selected QOLIE scales and Profile of Mood State scales. Correlations between patient and proxy scores ranged from 0.29 to 0.69 (all statistically significant at p < 0.005). A more detailed, final analysis of data for over 300 patients currently enrolled in the study will be published later.     

Validation of a new quality of life measure for children with epilepsy

PURPOSE: There is no adequate measure of health-related quality of life (HRQOL) specifically for children with epilepsy. The aim of this study was to develop an epilepsy-specific HRQOL questionnaire for children, covering five domains: physical function, emotional well-being, cognitive function, social function, and behavior. Second, we aimed to demonstrate the instrument's reliability and validity, and its sensitivity to differences in epilepsy severity. METHODS: The subjects were guardians of children with refractory epilepsy, whose syndrome had been defined by using video-EEG monitoring. Each family completed the developed epilepsy-specific HRQOL scale for children and two standard, generic measures of HRQOL. RESULTS: The results indicated that each of the scales of the questionnaire had good internal consistency reliability. Furthermore, each scale correlated more highly with theoretically similar scales on established, generic health measures than with theoretically dissimilar scales (construct validity). The sensitivity of the questionnaire to differences in epilepsy severity also was demonstrated. As seizure severity increased, HRQOL subscale scores decreased, independent of age, gender, age of seizure onset, and IQ. Further, there was a negative relation between the number of antiepileptic medications taken and measures of memory and language performance, which was independent of age, gender, age of seizure onset, IQ, and seizure severity. CONCLUSIONS: This study demonstrated that the developed HRQOL instrument is a reliable and valid measure and is sensitive to differences in epilepsy. These results indicate that this new instrument may be a viable medical or surgical outcome measure for children with epilepsy.     

Development of the Quality of Life in Epilepsy Inventory for Adolescents: The QOLIE-AD-48

PURPOSE: We report the development of an instrument to assess health-related quality of life (HRQOL) in adolescents with epilepsy. METHODS: A sample of 197 English-speaking adolescents (aged 11-17 years) with epilepsy completed a test questionnaire of 88 items. Also included were mastery and self-esteem scales to assess external validity. A parent simultaneously completed an 11-item questionnaire to evaluate the child's HRQOL. Both adolescent and parent questionnaires were repeated in 2-4 weeks. Demographic information and information pertaining to seizures were collected at baseline along with assessment of systemic and neurologic toxicity. RESULTS: The QOLIE-AD-48 contains 48 items in eight subscales: epilepsy impact (12 items), memory/concentration (10), attitudes toward epilepsy (four), physical functioning (five), stigma (six), social support (four), school behavior (four), health perceptions (three), and a total summary score, with higher scores indicating better HRQOL. Internal construct validity was demonstrated in a single-factor solution for the eight dimensions. All correlations were statistically significant at p < 0.05 level. Internal consistency reliability estimated by Cronbach's alpha coefficient was 0.74 for the summary score and ranged from a low of 0.52 (three-item Health Perceptions Scale) to 0.73-0.94 for the other individual scales. Good test-retest reliability was found for the overall measure (0.83). Summary score correlations with the two external validity scales, self-efficacy and self-esteem were 0.65 and 0.54, respectively. Statistically significant differences in summary scores indicating that HRQOL was increasingly better for adolescents as seizure severity decreases (no seizures = 77+/-13, low = 70+/-17, high = 63+/-17) were found among seizure-severity groups. CONCLUSIONS: These data describe the development of a robust instrument to evaluate HRQOL in adolescents with epilepsy. Empiric analyses provide strong evidence that the QOLIE-AD-48 is both a reliable and valid measure for adolescents with epilepsy.     

Development of the Quality of Life in Epilepsy Inventory

Summary: We developed an instrument to measure health-related quality of life (HRQOL) in epilepsy. A 99-item inventory was constructed from the RAND 36-Item Health Survey (generic core), with 9 additional generic items, 48 epilepsy-targeted items, and 6 other items concerning attitudes toward epilepsy and self-esteem. We administered the 99-item inventory to 304 adults with epilepsy at 25 epilepsy centers. Patients and patient-designated proxies completed the inventory and were retested 1–91 days later. A multitrait scaling analysis of these data led to retention of 86 items distributed in 17 multiitem scales (Cronbach's alpha ranged from 0.78 to 0.92). Factor analysis of the 17 multiitem scales yielded four underlying dimensions of health: an epilepsy-targeted dimension, a cognitive factor, mental health, and physical health. Construct validity was supported by significant patient-proxy correlations for all scales and correlations between neuropsychologic tests and self-reported emotional and cognitive function (all p values < 0.05). There were significant negative correlations between the four factor scores derived from the HRQOL scales and neurotoxicity, systemic toxicity, and health care utilization (except for the correlation between mental health factor and health care utilization; all p values < 0.05). Patients who were seizure-free in the preceding year reported better HRQOL for the overall score, three of the four factor scores, and 8 of the 17 scale scores than did patients with a high frequency of seizures. Relative validity analysis showed that the epilepsy-targeted factor and three of its four component scales were more sensitive to categorization of patients by severity of seizure frequency and type than scales tapping physical health, mental health, or cognitive function. These cross-sectional data support the reliability and validity of this measure of HRQOL in epilepsy. The addition of an epilepsy-targeted supplement to the generic core improved the sensitivity to severity of epilepsy. The 86 items included in the field testing were supplemented by three additional items to form the Quality of Life in Epilepsy (QOLIE-89) inventory.     

Patient-oriented outcome assessment after temporal lobectomy for refractory epilepsy.

OBJECTIVE: To determine patient-oriented outcome after anterior temporal lobectomy (ATL) for refractory epilepsy. BACKGROUND: Health-related quality of life (HRQOL) is an important component of the assessment of outcome from epilepsy surgery, but prior controlled studies of the effect of surgery on HRQOL are inconclusive. Direct assessment of the effect of surgery on patient concerns of living with epilepsy has not been reported. METHODS: We used reliable and valid instruments to compare HRQOL and patient concerns of 125 patients who had received an ATL more than than one year previously to a clinically similar group of 71 patients who were awaiting ATL. All patients were selected for surgery based on similar criteria. We also used bivariate correlation analysis and multivariate regression modeling to determine the association of traditional outcome variables with HRQOL. RESULTS: Patients who had undergone ATL reported significantly less concern of living with epilepsy in 16 of 20 items of the EFA Concerns Index and better HRQOL in 8 of 11 scales of the Epilepsy Surgery Inventory-55. Regression analysis in the postoperative group demonstrated that mood status, employment, driving, and antiepileptic drug (AED) cessation, but not seizure-free status or IQ, were associated with better HRQOL. CONCLUSIONS: Our findings support a positive affect of ATL on patient concerns and HRQOL in refractory temporal lobe epilepsy, although longitudinal studies are needed to corroborate these results. Mood, employment, driving ability, and AED use are important postoperative predictors of HRQOL.     

Relationships between seizure severity and health-related quality of life in refractory localization-related epilepsy

PURPOSE: To evaluate relationships between self-report measures of seizure severity and health-related quality of life (HRQOL) in people with refractory localization-related epilepsy. METHODS: A sample of 340 adults enrolled in a seven-center, prospective study of resective epilepsy surgery completed baseline questionnaires that included the Quality of Life in Epilepsy (QOLIE)-89 and a seven-item adaptation of the National Hospital Seizure Severity Scale. Associations between QOLIE-89 summary measures and both the total seizure severity scale score and individual seizure severity items were assessed, after adjustment for seizure frequency. RESULTS: The seizure severity measure had adequate scale score variability and reliability in this sample. Correlations between individual items in the scale did not exceed 0. 43. Product-moment partial correlations between the seizure severity scale and QOLIE-89 summary measures ranged from -0.17 to -0.29 (all p values <0.01). Of the seven seizure severity items, the average time before individuals perceived they were "really back to normal" after their seizures was broadly related to all domains of HRQOL (r values ranged from -0.16 to -0.30; p values <0.01). Severity of injury during seizures was the only other item having more than minimal associations with HRQOL, and it was selectively related to the physical health measure. Higher frequency of falls during seizures was modestly related to less employment. CONCLUSIONS: This seizure severity measure assesses constructs that are generally distinct from HRQOL, except for moderate and broad associations between HRQOL and patient's perceptions of the average duration of recovery time after seizures. Recovery time may potentially be a useful clinical indicator of seizure severity that reflects meaningful impairment of HRQOL in adults with frequent seizures.     

Validity of three measures of health-related quality of life in children with intractable epilepsy

PURPOSE: Validity studies on health-related quality of life (HRQOL) scales for pediatric epilepsy are few, and cross-validation with other samples has not been reported. This study was designed to assess the validity of three parent-rated measures of HRQOL in pediatric epilepsy: (a) the Impact of Childhood Illness Scale (ICI), (b) the Impact of Child Neurologic Handicap Scale (ICNH), and (c) the Hague Restrictions in Epilepsy Scale (HARCES). METHODS: Retrospective data were examined for 44 children with intractable epilepsy. Validity was assessed by evaluating differences across epilepsy severity groups as well as correlations between HRQOL scales and neurologic variables (seizure severity, epilepsy duration, current/prior antiepileptic medications) and psychosocial measures (emotional functioning, IQ, social skills, adaptive behavior). Scale overlap with a global QOL rating also was assessed. RESULTS: The HRQOL measures were moderately to highly intercorrelated. The scales differed in terms of their associations with criterion measures. The HARCES was related to the highest number of neurologic variables and the ICNH to the fewest. All three scales were related to psychosocial functioning and to global quality of life. CONCLUSIONS: The results of this study suggest that the three measures are likely adequate measures of HRQOL for use in intractable childhood epilepsy. The measures were highly intercorrelated, and they were all broadly related to criterion measures reflecting specific domains of HRQOL as well as global QOL. Some differences between scales emerged, however, that suggest care in choosing HRQOL instruments for children with epilepsy.     

The Washington Psychosocial Seizure Inventory (WPSI): psychometric evaluation and future applications.

The Washington Psychosocial Seizure Inventory (WPSI) clinical scales were developed via an empirical item selection approach and have been used widely to measure aspects of psychosocial functioning of patients with epilepsy. However, these empirically derived clinical scales have not been assessed psychometrically using a modern item response theory-based model. The goals of this study were to: (1) evaluate how items in each clinical scale performed in such a way as to represent the underlying constructs being measured; and (2) derive a shorter version while maintaining measurement precision. WPSI item response data from 145 adults with epilepsy collected for an evaluation study of an intervention to pact negative attributional style in epilepsy were used. The dichotomous Rasch model suitable for the true-false response choices was used to analyse each clinical scale separately. Most items within each scale fit the measurement model well, with very few exceptions. All items, therefore, were retained. A method, based on computerised adaptive testing (CAT), is offered for shortening the WPSI using a psychosocial outcomes item bank derived from the study. Individuals' specific levels of functioning are used to derive measures of their psychosocial functioning with a minimum number of items.     

Properties of the 15D and EQ-5D utility measures in a community sample of people with epilepsy

To perform economic evaluation studies in epilepsy using utilities, such as cost-utility analyses, it is necessary to have reliable and valid instruments for eliciting people's preferences. The objective of this study was to assess the reliability and validity of two multiattribute utility measures in a community sample of 397 people with epilepsy. We assessed the test-retest reliability of individual questionnaire items and aggregate scores. Additionally, construct validity was assessed by correlating items of the EQ-5D with items of the 15D health status questionnaire, and discriminant validity was assessed by comparing scores for known groups. The test-retest reliabilities for the individual items of the 15D (weighted kappa 0.59-0.90, except mobility with only 0.28) and the EQ-5D (weighted kappa 0.49-0.86) were acceptable. For the composite utility scores the test-retest reliability was better (intraclass correlation coefficient 0.93 for both 15D and the EQ-5D). Spearman's rank correlations between EQ-5D single item scores and corresponding 15D single item scores were high (rho 0.34-0.79) and generally higher than the associations between non-corresponding items. Some EQ-5D and 15D items discriminated well between patients according to seizure status, psychiatric comorbidity and working status; less well after antiepileptic drug use and neurologic comorbidity. Both the EQ-5D and 15D were reliable instruments and showed properties supporting the construct validity of both measures.     

Neuroticism in Temporal Lobe Epilepsy: Assessment and Implications for Pre- and Postoperative Psychosocial Adjustment and Health-Related Quality of Life

Summary: We assessed 77 candidates for epilepsy surgery to determine the association among neuroticism (a dimension of personality characterized by chronic negative emotions and behaviors), psychosocial adjustment as measured by the Washington Psychosocial Seizure Inventory (WPSI), and health-related quality of life (HRQOL) as measured by the Epilepsy Surgery Inventory 55 (ESI-55). Minnesota Multiphasic Personality Inventory 2 (MMPI-2) Neuroticism scale scores were significantly correlated with many domains of patient-perceived psychosocial adjustment and HRQOL regardless of frequency or type of seizures. We then followed 45 of the patients who subsequently underwent epilepsy surgery to determine the influence of neuroticism on postoperative functioning. Two-way analysis of variance (ANOVA) indicated that patients with high preoperative neuroticism had significantly poorer postoperative psychosocial adjustment and HRQOL scores than patients who had low or moderate preoperative neuroticism scores. These results support the validity of the MMPI-2 as a useful measure of neuroticism. Preoperative neuroticism has an important influence on postoperative psychosocial adjustment and HRQOL that is independent of postoperative seizure outcome. Understanding the influence of personality variables, such as neuroticism, on psychosocial functioning both before and after epilepsy surgery is essential in managing intractable seizures.     

Outcome assessment for epilepsy surgery: The impact of measuring health-related quality of life

Epilepsy surgery is an increasingly common treatment for intractable epilepsy; yet there is no clear consensus among experts on how to report epilepsy surgery outcome. Most published outcome reporting systems focus on seizure frequency and type but differ in how they define clinically distinct outcome categories. We used a reliable and valid measure of self-reported health-related quality of life (HRQOL), the Epilepsy Surgery Inventory (ESI)-55, as an external standard by which to evaluate seven previously published, seizure-based outcome classification systems. The ESI-55 was administered to 133 adults who had previously undergone surgery for intractable epilepsy, and results were linked to data on their seizure occurrence before and after surgery (over the year prior to their HRQOL reports). These 133 patients were classified according to each seizure-based outcome system, and variation in HRQOL across outcome groups was evaluated using analysis of variance. Results reveal noteworthy variation in the extent to which different systems reflect patients' HRQOL at follow-up. We modified existing systems to derive a seizure-based surgery outcome system that most closely reflects HRQOL when applied over the latest 1-year postoperative interval.     

Development of a stroke-specific quality of life scale.

BACKGROUND AND PURPOSE: Clinical stroke trials are increasingly measuring patient-centered outcomes such as functional status and health-related quality of life (HRQOL). No stroke-specific HRQOL measure is currently available. This study presents the initial development of a valid, reliable, and responsive stroke-specific quality of life (SS-QOL) measure, for use in stroke trials. METHODS: Domains and items for the SS-QOL were developed from patient interviews. The SS-QOL, Short Form 36, Beck Depression Inventory, National Institutes of Health Stroke Scale, and Barthel Index were administered to patients 1 and 3 months after ischemic stroke. Items were eliminated with the use of standard psychometric criteria. Construct validity was assessed by comparing domain scores with similar domains of established measures. Domain responsiveness was assessed with standardized effect sizes. RESULTS: All 12 domains of the SS-QOL were unidimensional. In the final 49-item scale, all domains demonstrated excellent internal reliability (Cronbach's alpha values for each domain >/=0.73). Most domains were moderately correlated with similar domains of established outcome measures (r2 range, 0.3 to 0.5). Most domains were responsive to change (standardized effect sizes >0.4). One- and 3-month SS-QOL scores were associated with patients' self-report of HRQOL compared with before their stroke (P<0.001). CONCLUSIONS: The SS-QOL measures HRQOL, its primary underlying construct, in stroke patients. Preliminary results regarding the reliability, validity, and responsiveness of the SS-QOL are encouraging. Further studies in diverse stroke populations are needed.     

Predictors of health-related and global quality of life among young adults with difficult-to-treat epilepsy and mild intellectual disability

ObjectiveThis study evaluated predictors of health-related quality of life (HRQOL) and global quality of life (QOL) among young adults with difficult-to-treat epilepsy and mild intellectual disability.MethodsOne hundred and forty-two persons with epilepsy and cognitive problems were routinely screened on HRQOL, global QOL, and psychological distress four weeks after admission to a time-limited residential rehabilitation unit. The PESOS scales (PE = PErformance, SO = SOciodemographic aspects, S = Subjective evaluation/estimation) on epilepsy-specific problems were administered as measures of HRQOL; a questionnaire on life satisfaction and an item on overall QOL were used as measures of global QOL. Psychological distress was captured with the Symptom Checklist 90-R. Further data were gained from medical files. Quality-of- life predictors were identified using univariate methods and stepwise regression analyses.ResultsPsychological distress was the only predictor of all HRQOL and global QOL parameters. Seizure frequency was a predictor of most HRQOL variables. Other epilepsy variables affected only some HRQOL variables but were not associated with global QOL. Health-related quality of life did not seem to be strongly impaired. Only low correlations were found between HRQOL and global QOL.ConclusionThe notion of psychological distress as the most influential predictor of all QOL measures is in line with most findings on QOL in epilepsy. Former observations of weak associations between HRQOL and global QOL among patients with epilepsy and mild intellectual disability are supported. Thus, interventions to reduce psychological distress, besides epilepsy treatment, seem to be of great importance to improve QOL.     

Health-related quality of life outcome in medically refractory epilepsy treated with anterior temporal lobectomy

PURPOSE: A prospective study to investigate health-related quality of life (HRQOL) outcome in patients with temporal lobe epilepsy treated with anterior temporal lobectomy (ATL). METHODS: The majority of the patients with medically refractory focal epilepsy had Quality of Life in Epilepsy-89 (QOLIE-89) assessment at the time of prolonged video/EEG monitoring as part of their presurgical evaluation. Thirty-seven patients who were not treated surgically constituted the control group, and 53 patients who underwent ATL made up the surgery group. Both control and surgery groups had HRQOL assessment repeated at approximately 1-and 2-year intervals. Repeated measures analysis of variance (ANOVA) was used to test for differences between the two groups. RESULTS: For the overall score and almost every scale, the surgery group had a higher baseline mean than the control group. Because of this baseline difference, change scores were used in further analysis. The overall score and 10 of 17 scales in QOLIE-89 showed significant HRQOL improvement after ATL, and the improvement was significant relative to score changes of the nonsurgical comparison group. Scores improved in overall QOL, emotional well-being, attention/concentration, language, social isolation, health perception, role limitations-physical, work/drive/social, health discouragement, and seizure worry. For the first five scales, there was group-time interaction; the improvement was significantly more on the 2-year than on the 1-year follow-up. When the surgery patients were divided into four categories (class IA-, completely seizure free; class IA+, seizure free with aura; class II, rare seizures; class III, worthwhile improvement in seizure control; and class IV, no improvement), the improved HRQOL in the surgery group was almost entirely contributed by the class IA- outcome patients who were totally seizure free. The class IA+ patients with continuing aurae and class II/III/IV patients had no significant improvement in their overall HRQOL scores at 1-or 2-year follow-up. CONCLUSIONS: Overall score and 10 of the 17 scales of QOLIE-89 significantly improved in patients with medically refractory temporal lobe epilepsy after ATL. For some scales, there was delay in the improvement to manifest. The HRQOL improvement was related to achieving an entirely seizure-free status (i.e., no seizures or aurae postoperatively).     

Construct and concurrent validation of the MG‐QOL15 in the practice setting

Health‐related quality of life (HRQOL) estimates can play an important role in patient care by providing information about the patient's perception of impairment and disability and the degree to which the patient tolerates disease manifestations. The 15‐item myasthenia gravis quality of life scale (MG‐QOL15) is an HRQOL evaluative instrument specific to patients with myasthenia gravis (MG) that was designed to be easy to administer and interpret. In this multicenter study we demonstrate the construct validity of the MG‐QOL15 in the practice setting. To assess the construct validity, score distributions were examined for test items in different MG patient groups that represent the clinical spectrum of the disease. For example, patients in remission more frequently scored test items as normal than did patients in other groups. Patients with lower (better) MG composite scores also more frequently scored items as normal than did patients with higher (worse) scores. There was also appropriate correlation between the MG‐QOL15 and the other MG‐specific scales studied. The study findings shed light on what troubles MG patients. The MG‐QOL15 has construct validity in the clinical practice setting and represents an efficient and valuable tool for assessing HRQOL for patients with MG. Muscle Nerve, 2010     

Development of the PedsQL™ Epilepsy Module: Focus group and cognitive interviews

Youth with epilepsy have impaired health-related quality of life (HRQOL). Existing epilepsy-specific HRQOL measures are limited by not having parallel self- and parent-proxy versions, having a restricted age range, not being inclusive of children with developmental disabilities, or being too lengthy for use in a clinical setting. Generic HRQOL measures do not adequately capture the idiosyncrasies of epilepsy. The purpose of the present study was to develop items and content validity for the PedsQL™ Epilepsy Module.MethodsAn iterative qualitative process of conducting focus group interviews with families of children with epilepsy, obtaining expert input, and conducting cognitive interviews and debriefing was utilized to develop empirically derived content for the instrument. Eleven health providers with expertise in pediatric epilepsy from across the country provided feedback on the conceptual model and content, including epileptologists, nurse practitioners, social workers, and psychologists. Ten pediatric patients (age 4–16 years) with a diagnosis of epilepsy and 11 parents participated in focus groups. Thirteen pediatric patients (age 5–17 years) and 17 parents participated in cognitive interviews.ResultsFocus groups, expert input, and cognitive debriefing resulted in 6 final domains including restrictions, seizure management, cognitive/executive functioning, social, sleep/fatigue, and mood/behavior. Patient self-report versions ranged from 30 to 33 items and parent proxy-report versions ranged from 26 to 33 items, with the toddler and young child versions having fewer items.ConclusionsStandardized qualitative methodology was employed to develop the items and content for the novel PedsQL™ Epilepsy Module. The PedsQL™ Epilepsy Module has the potential to enhance clinical decision-making in pediatric epilepsy by capturing and monitoring important patient-identified contributors to HRQOL.     

Does adding MS-specific items to a generic measure (the SF-36) improve measurement?

OBJECTIVE: The 36-item Short Form Health Survey Questionnaire (SF-36) is a widely used generic health status measure. Recently it has been adapted to produce a disease-specific measure for MS-the 54-item Multiple Sclerosis Quality of Life Scale (MSQOL-54)-composed of five unchanged SF-36 scales; three altered SF-36 scales (one item added to each scale); and five new scales incorporating 15 additional items. This study evaluates the impact of these additions by comparing the measurement properties of the MSQOL-54 with the SF-36. METHODS: A total of 150 patients with MS, representing a broad spectrum of disease severity, completed a range of questionnaires, which included the MSQOL-54 (from which the SF-36 score was computed). Of these, 44 people completed the measures before and after inpatient rehabilitation to evaluate responsiveness. Standard psychometric methods were used to evaluate the measurement properties. RESULTS: The measurement properties of the unchanged scales, inevitably, remain identical. Those of the three altered scales are virtually identical. Of the five new scales, the validity of the two sexual scales is questioned because of the high percentage of missing data, and the validity of the overall quality-of-life scale is limited as demonstrated by the low to moderate correlations with other related and unrelated measures. Responsiveness of the new scales also appears limited. CONCLUSION: Modifying existing measures by simply adding clinically chosen items may not be as useful as anticipated in improving the measurement properties of an instrument.     

Health-related quality of life in epilepsy: findings obtained with a new Italian instrument

The aim of the present study was to evaluate the Epi-QoL, a new Italian-specific measure of health-related quality of life (HRQOL) for adults with epilepsy; the clinical variables that affected the HRQOL score were also assessed. The Epi-QoL is a 46-item self-administered questionnaire focusing on six domains: Physical Functioning, Cognitive Functioning, Emotional Well-Being, Social Functioning, Seizure Worry, and Medication Effects. Eight hundred fifteen patients recruited from 24 secondary and tertiary Italian centers for the care of epilepsy were assessed. The results supported the reliability and validity of the Epi-QoL as a measure of HRQOL. The variables that significantly affected HRQOL scores were: geographic area, gender, seizure frequency, prognostic categories, number of medications, comorbidity, presence of cognitive impairment, psychiatric disturbances, and disability. We believe that a new specific questionnaire for the evaluation of HRQOL in Italy can contribute much to the understanding of the influence of epilepsy on patients' lives.     

An item response analysis of the international restless legs syndrome study group rating scale for restless legs syndrome

BACKGROUND AND PURPOSE: Restless legs syndrome (RLS) is a common central nervous system disorder; however, there is currently a lack of well-validated and easily-administered measures of RLS severity available. The International Restless Legs Syndrome Study Group has recently developed a 10-item scale to meet this need. The International Restless Legs Severity Scale (IRLS) has been shown to have a high degree of reliability, validity, and internal consistency. In order to further demonstrate the validity of the IRLS, the present study examined the relationship between scores on individual IRLS items and overall RLS severity. PATIENTS AND METHODS: The 10-item IRLS was administered to 196 RLS patients. Option characteristic curves (the probability of scoring different options for a given item as a function of overall IRLS score) were generated in order to illustrate the scoring patterns for each item across the range of total RLS severity. Item characteristic curves (the expected score on an item as a function of overall IRLS score) were also generated to illustrate the relationship between scores on the individual items and total RLS severity. RESULTS: The IRLS items demonstrated excellent item response properties, with option and item characteristic curves closely approximating those of an ideal item. Item 3 (relief of arm or leg discomfort from moving around) was the most problematic item in that a 'floor' effect was evident; however, the item response characteristics for this item were still acceptable. CONCLUSIONS: Each IRLS item showed a good relationship between responses on that item and overall RLS severity, providing further evidence for the validity of the IRLS as a measure of RLS severity in RLS patients.     

Psychometric properties of the Dutch version of the Washington Psychosocial Seizure Inventory

PURPOSE: The psychometric properties of the Dutch version of the Washington Psychosocial Seizure Inventory (WPSI) were investigated. METHODS: The dimensional structure, reliability, and validity of the WPSI scales were assessed in 218 patients with epilepsy. The association with relevant patient and epilepsy characteristics also was studied. RESULTS: An exploratory seven-factor principal components analysis was compared with a confirmatory factor analysis, and a loss of 3.36% of total variance was found. To increase the homogeneity of the scales, 30 items with low factor loadings or highest factor loading on the wrong clinical scale were excluded. This resulted in a higher amount of explained variance and improvement of the factor loadings of the remaining items. The reliability and validity of the WPSI scales was satisfactory to good. No clinically relevant associations were found between the WPSI scales and patient and epilepsy characteristics. CONCLUSIONS: The factor structure, reliability, and validity of the Dutch translation of the WPSI are good and comparable to the original English version of Dodrill. The results demonstrate that shortening the WPSI makes the inventory more reliable and the clinical scales less dependent on each other.