Psychometric properties of the EuroQol Five Dimensional Questionnaire (EQ-5D-3L) in caregivers of autistic children

Purpose

This study aimed to ascertain the psychometric properties of EuroQol Five Dimensional Questionnaire (EQ-5D-3L) in primary caregivers of children with autism. The convergent validity, discriminant validity, known-groups validity, internal consistency reliability, and floor and ceiling effects of EQ-5D-3L were analyzed.

Methods

A cross-sectional design was used for study purposes. Through an online survey, relevant study information was collected from 316 primary caregivers of children with autism. Study participants were from families of children with autism living in the United States who were registered with the Interactive Autism Network. Convergent validity of the EQ-5D-3L was assessed through its correlation with other measures of similar constructs. Discriminant validity was assessed by observing the correlation of EQ-5D-3L domains with theoretically unrelated constructs. Known-groups validity was tested by comparing EQ-5D-3L index and visual analog scale (VAS) scores across levels of autism severity among the care recipients. Internal consistency reliability of EQ-5D-3L was tested. Lastly, floor and ceiling effects of EQ-5D-3L were assessed.

Results

More than 60 % of participants reported problems of ‘anxiety/depression.’ Convergent and discriminant validity of the EQ-5D-3L was good. Significant correlation (convergent validity) was observed among EQ-5D-3L index and VAS and (SF-12v2) physical component summary and mental component summary scores. Caregivers’ EQ-5D-3L index and VAS scores varied by levels of autism severity among care recipients, providing evidence of known-groups validity. Reliability assessed through Cronbach’s alpha was less than satisfactory; however, corrected item-total correlations were adequate.

Conclusions

The EQ-5D-3L is a psychometrically sound tool to elicit health state preferences among caregivers of children with autism.     

Psychometric properties and Dutch norm data of the PedsQL Multidimensional Fatigue Scale for Young Adults

Purpose

The aim of this study was to assess internal consistency and construct validity (known-groups validity) and to provide Dutch norm data for the Dutch Pediatric Quality of Life Inventory Multidimensional Fatigue Scale for Young Adults ages 18–30 years (PedsQL fatigue_YA).

Methods

A Dutch sample of 649 young adults completed online a sociodemographic questionnaire and the PedsQL fatigue_YA including three subscales: general fatigue, sleep/rest fatigue and cognitive fatigue (0–100: Higher scores indicate less fatigue symptoms).

Results

The PedsQL fatigue_YA showed satisfactory to good internal consistency (Cronbach’s alpha = .70–.94), except for one scale (.68). The mean scale scores were 68.23 (SD 19.15) for ‘general fatigue,’ 67.04 (SD 15.54) for ‘sleep/rest fatigue’ and 74.62 (SD 19.02) for ‘cognitive fatigue.’ Men reported significantly higher scores on ‘general fatigue’ and ‘sleep/rest fatigue’ than women. The PedsQL fatigue_YA distinguished between healthy young adults and young adults with chronic health conditions, with higher scores on all scales in healthy young adults than in those with a chronic health condition.

Conclusion

The results demonstrate good psychometric properties of the PedsQL fatigue_YA in a sample of Dutch young adults. With the current norms available, it is possible to evaluate fatigue in the Netherlands from childhood to adulthood with the PedsQL Multidimensional Fatigue Scale.     

Activity limitation and participation restrictions of breast cancer patients receiving chemotherapy: psychometric properties and validation of the Chinese version of the WHODAS 2.0

Purpose

This study sought to determine the psychometric properties of the Chinese version of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) in a sample of 402 primary breast cancer patients receiving chemotherapy after surgery.

Methods

Four-hundred and two subjects were interviewed with the Chinese version of the WHODAS 2.0. Patients also completed the Functional Assessment of Cancer Therapy-Breast (FACT-B). Internal consistency reliability was measured by Cronbach’s α. Spearman correlation coefficients between total scores and subscales of FACT-B and WHODAS 2.0 were examined to get the convergent validity. Independent sample t test was applied to test discriminant validity by comparing the difference of disability scores for different degree of relevant symptoms. The factor structure of the WHODAS 2.0 was examined by Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis.

Results

The Chinese version of the WHODAS 2.0 showed satisfactory internal consistency (r, 0.72–0.92), convergent validity and discriminant validity. After 4 items(item D2.2: standing up; D3.3: eating; D4.5: sexual activities; and D6.3: living with dignity) were excluded, EFA identified seven separate factors for ‘Self-care and Household activities,’ ‘Getting along with people,’ ‘Getting around,’ ‘Understanding,’ ‘Communicating,’ ‘Participation in society’ and ‘Family burden’(explained variance 72.13 %). The reduced model also presented the best fit [Confirmatory Fit Index = 0.914, Tucker-Lewis Index = 0.900, Root Mean Square Error of Approximation = 0.069] compared with the model suggested by EFA and hypothesized a prior.

Conclusions

Overall, the Chinese version of the WHODAS 2.0 is a reliable and valid instrument for measuring activity limitation and participation restrictions in Chinese breast cancer patients receiving chemotherapy.     

Validation of the Korean version of the Pain Catastrophizing Scale in patients with chronic non-cancer pain

Purpose

Pain catastrophizing often has been measured using the Pain Catastrophizing Scale (PCS). Studies of the PCS nearly consistently support its three-factor structure (i.e., helplessness, magnification, and rumination) and satisfactory psychometric properties across different countries and languages. This study aimed to assess the generalizability of the three-factor structure of the PCS to Korean patients with chronic non-cancer pain and to investigate reliability, measurement error, and construct validity of a Korean version of the PCS (K-PCS).

Methods

A total of 182 patients with chronic pain seeking treatment in a tertiary pain center located in Seoul, Korea, participated.

Results

Confirmatory factor analysis demonstrated the adequacy of the three-factor structure of the K-PCS; ‘helplessness,’ ‘magnification,’ and ‘rumination.’ The internal consistency for ‘helplessness,’ ‘magnification,’ ‘rumination,’ and total scale of the K-PCS were Cronbach’s α = .90, .71, .86, and .93, respectively; test–retest stability, ICC = .77, .73, .65, and .79, respectively; the standard estimation of measurement, 1.93, 1.34, 2.13, and 3.72, respectively; the minimum detectable change, 5.33, 3.70, 5.89, and 10.28, respectively; and the limits of agreement, ?7.66 to 9.20, ?5.07 to 5.01, ?7.30 to 6.86, and ?15.26 to 16.46, respectively. At least moderate positive correlations were observed between the K-PCS and pain intensity, depression, and pain-related anxiety, and moderate negative correlations between the K-PCS and physical and psychological functioning.

Conclusion

The K-PCS has the reliability, measurement error, and construct validity support for assessing pain catastrophizing in a Korean patient sample with chronic non-cancer pain.     

Development of the Italian version of the 42-item Chronic Pain Coping Inventory, CPCI-I: cross-cultural adaptation, factor analysis, reliability and validity

Purpose

The aim of this study was to translate and adapt the Italian version of the Chronic Pain Coping Inventory (CPCI) and validate the translation in subjects with chronic non-specific pain of the locomotor system.

Methods

The questionnaire was developed following international recommendations. The psychometric analyses included factor analysis, reliability by internal consistency (Cronbach’s alpha) and test–retest reliability (intraclass coefficient correlation, ICC), and construct validity by calculating the correlations between the subscales of the CPCI with measures of pain (numerical rating scale, NRS), disability (SIP-Roland Scale) and depression (CES-D) (Pearson’s correlation).

Results

The CPCI was satisfactorily administered to 270 subjects with chronic non-specific pain. Results of confirmatory factor analyses revealed that, of the CPCI-I 8 subscales, 6 demonstrated good data-model fit (CFI and NFI ≥0.90, RMSEA ≤0.08). Cronbach’s alpha was satisfactory in all of the subscales (0.71–0.80); the ICCs were good/excellent in all of the subscales (0.80–0.91). The correlations with the NRS, SIP-Roland and CES-D were poor in most cases as only the CPCI-Guarding subscale moderately correlated with disability (r = 0.31).

Conclusion

The CPCI was successfully translated into Italian and proved to have a good factorial structure and psychometric properties similar to the original and adapted versions. The use of the Italian version of the CPCI is recommended for clinical and research purposes.     

Pay-for-performance in disease management: a systematic review of the literature

Background

There is a lack of acceptable, reliable, and valid survey instruments to measure conceptual research utilization (CRU). In this study, we investigated the psychometric properties of a newly developed scale (the CRU Scale).

Methods

We used the Standards for Educational and Psychological Testing as a validation framework to assess four sources of validity evidence: content, response processes, internal structure, and relations to other variables. A panel of nine international research utilization experts performed a formal content validity assessment. To determine response process validity, we conducted a series of one-on-one scale administration sessions with 10 healthcare aides. Internal structure and relations to other variables validity was examined using CRU Scale response data from a sample of 707 healthcare aides working in 30 urban Canadian nursing homes. Principal components analysis and confirmatory factor analyses were conducted to determine internal structure. Relations to other variables were examined using: (1) bivariate correlations; (2) change in mean values of CRU with increasing levels of other kinds of research utilization; and (3) multivariate linear regression.

Results

Content validity index scores for the five items ranged from 0.55 to 1.00. The principal components analysis predicted a 5-item 1-factor model. This was inconsistent with the findings from the confirmatory factor analysis, which showed best fit for a 4-item 1-factor model. Bivariate associations between CRU and other kinds of research utilization were statistically significant (p < 0.01) for the latent CRU scale score and all five CRU items. The CRU scale score was also shown to be significant predictor of overall research utilization in multivariate linear regression.

Conclusions

The CRU scale showed acceptable initial psychometric properties with respect to responses from healthcare aides in nursing homes. Based on our validity, reliability, and acceptability analyses, we recommend using a reduced (four-item) version of the CRU scale to yield sound assessments of CRU by healthcare aides. Refinement to the wording of one item is also needed. Planned future research will include: latent scale scoring, identification of variables that predict and are outcomes to conceptual research use, and longitudinal work to determine CRU Scale sensitivity to change.     

Personal hygiene among military personnel: developing and testing a self-administered scale

Objective

Good personal hygiene (PH) behavior is recommended to prevent contagious diseases, and members of military forces may be at high risk for contracting contagious diseases. The aim of this study was to develop and test a new questionnaire on PH for soldiers.

Methods

Participants were all male and from different military settings throughout Iran. Using a five-stage guideline, a panel of experts in the Persian language (Farsi) developed a 21-item self-administered questionnaire. Face and content validity of the first-draft items were assessed. The questionnaire was then translated and subsequently back-translated into English, and both the Farsi and English versions were tested in pilot studies. The consistency and stability of the questionnaire were tested using Cronbach’s alpha and the test–retest strategy. The final scale was administered to a sample of 502 military personnel. Explanatory and confirmatory factor analyses evaluated the structure of the scale. Both the convergent and discriminative validity of the scale were also determined.

Results

Cronbach’s alpha coefficients were >0.85. Principal component analysis demonstrated a uni-dimensional structure that explained 59 % of the variance in PH behaviors. Confirmatory factor analysis indicated a good fit (goodness-of-fit index = 0.902; comparative fitness index = 0.923; root mean square error of approximation = 0.0085).

Conclusions

The results show that this new PH scale has solid psychometric properties for testing PH behaviors among an Iranian sample of military personnel. We conclude that this scale can be a useful tool for assessing PH behaviors in military personnel. Further research is needed to determine the scale’s value in other countries and cultures.     

Screening for frailty in elderly subjects living at home: Validation of the modified Short Emergency Geriatric Assessment (SEGAm) instrument

Objectives

To validate the modified version of the Short Emergency Geriatric Assessment (SEGAm) frailty instrument in elderly people living at home.

Design

Longitudinal, prospective, multicentre study.

Setting

Four departments (Ardennes, Marne, Meurthe-et-Moselle, Meuse) in two French Regions (Champagne-Ardenne and Lorraine).

Participants

Subjects aged 65 years or more, living at home, who could read and understand French, with a degree of autonomy corresponding to groups 5, or 6 in the AGGIR autonomy evaluation scale.

Measurements

Assessment included demographic characteristics, comprehensive geriatric assessment, and the SEGAm instrument. Psychometric validation was used to study feasibility and acceptability, internal structure validity, reliability, and discriminant validity of the SEGAm instrument.

Results

Between July 1st 2012 and March 31st 2013, 167 patients were included in the study. Averaged age was 77±7 years, the majority were women (70.7%). Feasibility and acceptability of the SEGAm instrument were excellent: we observed no refusal to participate, no drop-out during administration, no missing items, no ceiling or floor effects, and the administration time was short (5.0±3.5 min). By factor analysis, the instrument proved to be unidimensional. It showed good internal consistency (Cronbach’s alpha coefficient: 0.68) and good test-retest (intra-class correlation: 0.88) at 7 days interval. Discriminant validity showed a significant difference, mainly for nutritional status, fall risk, dependency, mood and depression risk, and comorbidities.

Conclusion

Based on these psychometric properties, the SEGAm appears to be an easy-to-use instrument that is particularly suitable for use in the community to identify frail elderly people who could benefit from early targeted interventions.     

Validation of the Arabic version of the EORTC quality of life questionnaire among cancer patients in Lebanon

Purpose

The objective of this article was to evaluate the psychometric properties of the translated Lebanese Arabic version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 in a sample of adult cancer patients in Lebanon.

Methods

The EORTC QLQ-C30 was translated into Lebanese Arabic and administered to a convenient sample of 200 adult patients diagnosed with cancer at a tertiary care center in Lebanon between 2009 and 2010. The psychometric indices assessed were reliability, multitrait scaling analysis, construct validity, and confirmatory factor analysis.

Results

Six out of nine subscales had Cronbach’s alpha coefficients above 0.70. Multitrait scaling analysis showed that all item-scale correlation coefficients met the set standards of convergent validity with the exception of item 5 only (95.8 %). In addition, 79.7 % of the item-scale correlation coefficients met the criterion for discriminant validity. In inter-scale correlations, all conceptually related scales had correlation coefficients of ≥0.40 with the exception of role functioning and fatigue scales having an undesirable correlation coefficient of ?0.76. In known-groups comparison, the instrument differentiated significantly between some of the subscales with respect to education, employment, and age. CFA showed an almost good fit (GFI = 0.87) with respect to our current data set.

Conclusion

The translated Lebanese Arabic version of the EORTC QLQ-C30 is a reliable and valid instrument that can be used to assess the quality of life of Lebanese cancer patients.     

Cross-cultural evaluation of the French version of the LEIPAD, a health-related quality of life instrument for use in the elderly living at home

Purpose

To cross-culturally adapt a French version of the LEIPAD, a self-administered questionnaire assessing the health-related quality of life (HRQoL) in adults aged 65 years and over living at home, and to evaluate its psychometric properties.

Methods

After having translated LEIPAD in accordance with guidelines, we studied psychometric properties: reliability and construct validity—factor analysis, relationships between items and scales, internal consistency, concurrent validity with the Medical Outcome Study Short-Form 36 and known-groups validity.

Results

The results obtained in a sample of 195 elderly from the general population showed very good acceptability, with response rates superior to 93 %. Exploratory factor analysis extracted eight factors providing a multidimensionality structure with five misclassifications of items in the seven theoretical scales. Good internal consistency (Cronbach’s alpha ranging from 0.73 and 0.86) and strong test–retest reliability (ICCs higher than 0.80 for six scales and 0.70 for one) were demonstrated. Concurrent validity with the SF-36 showed small to strong expected correlations.

Conclusion

This first evaluation of the French version of LEIPAD’s psychometric properties provides evidence in construct validity and reliability. It would allow HRQoL assessment in clinical and common practice, and investigators would be able to take part in national and international research projects.     

An evaluation of the psychometric properties of the sf-12v2 health survey among adults with hemophilia

Background

This study examined the psychometric properties of version 2 of the SF-12 Health Survey (SF-12v2) among adults with hemophilia in the United States.

Methods

This study employed a cross-sectional design using web-based and paper-based self-administered surveys. Hemophilia patients were recruited using an online panel and at a hemophilia treatment clinic. The psychometric properties of the SF-12v2 were assessed in terms of construct validity, internal consistency reliability, and presence of floor and ceiling effects.

Results

A total of 218 adults with hemophilia completed the survey, with most recruited via the online panel (78%). Confirmatory factor analysis using the WLSMV estimator in Mplus supported a two-factor model for the SF-12v2 where the physical functioning, role physical, bodily pain, and general health items loaded onto a latent physical factor (LPF) and the role emotional, mental health, social functioning, and vitality items loaded onto a latent mental factor (LMF). Model fit statistics for the two-factor model were: Chi-square [df]?=?172.778 [48]; CFI?=?0.972; TLI?=?0.962; RMSEA [90% CI]?=?0.109 [0.092–0.127]; WRMR?=?0.947. Correlated residuals for items belonging to similar domains were estimated and there was a significant correlation between LPF and LMF. All standardized factor loadings were strong and statistically significant, indicating adequate convergent validity. Item-to-other scale correlations were lower than item-to-hypothesized scale correlations suggesting good item discriminant validity. Model testing revealed that LPF and LMF were not perfectly correlated, suggesting adequate construct discriminant validity. Increasing levels of symptom severity were associated with significant decreases in physical component summary (PCS) and mental component summary (MCS) scores, supporting known-groups validity. Internal consistency reliability was satisfactory, with Cronbach’s alpha of 0.848 for the LPF and 0.785 for the LMF items. Finally, none of the participants received the least or maximum possible PCS or MCS score, indicating the absence of floor and ceiling effects.

Conclusions

Overall, the SF-12v2 was found to have adequate psychometric validity in our sample of adults with hemophilia. These results add to the growing evidence of psychometric validity of the SF-12v2 in different patient populations including hemophilia.

     

Psychometric evaluation of the Taiwan Chinese version of the EORTC QLQ-PR25 for HRQOL assessment in prostate cancer patients

Aim

To psychometrically validate the Spanish version of the self-administered 2-item GAD-2 scale for screening probable patients with generalised anxiety disorder (GAD).

Methods

The GAD-2 was self-administered by patients diagnosed with GAD according to DSM-IV criteria and by age- and sex-matched controls who were recruited at random in mental health and primary care centres. Criteria validity was explored using ROC curve analysis, and sensitivity, specificity and positive and negative predictive values were determined for different cut-off values. Concurrent validity was also established using the HAM-A, HADS, and WHODAS II scales.

Results

The study sample consisted of 212 subjects (106 patients with GAD) with a mean age of 50.38?years (SD?=?16.76). No items of the scale were left blank. Floor and ceiling effects were negligible. No patients with GAD had to be assisted to complete the questionnaire. Reliability (internal consistency) was high; Cronbach??s ???=?0.875. A cut-off point of 3 showed adequate sensitivity (91.5%) and specificity (85.8%), with a statistically significant area under the curve (AUC?=?0.937, p?<?0.001), to distinguish GAD patients from controls. Concurrent validity was also high and significant with HAM-A (0.806, p?<?0.001), HADS (anxiety domain, 0.825, p?<?0.001) and WHO-DAS II (0.642, p?<?0.001) scales.

Conclusion

The Spanish version of the GAD-2 scale has been shown to have appropriate psychometric properties to rapidly detect probable cases of GAD in the Spanish cultural context under routine clinical practice conditions.     

Translation and psychometric testing of the Farsi version of the Seattle angina questionnaire

Background

Angina pectoris causes substantial psychological and functional disabilities and adversely effects quality of life in patients. The aim of this study was to investigate the psychometric properties including validity and reliability of the Farsi version of the Seattle angina questionnaire.

Methods

The ‘forward-backward’ procedure was applied to translate this questionnaire from English to Farsi. The translated version of the Seattle angina questionnaire was assessed in terms of validity and reliability with a convenience sample of 200 patients suffering from angina pectoris who were recruited from the inpatient ward (post CCU) and outpatient department at two teaching hospitals in an urban area of Iran. Validity was assessed using content, face and construct validity. The calculation of the Cronbach’s alpha coefficient and the test-retest method helped with the assessment of reliability of the questionnaire’s five subscales. Construct validity of the questionnaire was evaluated using exploratory factor analysis.

Results

The results of exploratory factor analysis indicated a five-factor solution for the questionnaire including ‘physical limitation in middle to strenuous activities’, ‘physical limitation in slight activities’, ‘angina pattern and discomfort of treatment’, ‘treatment satisfaction’ and ‘disease perception’ that jointly accounted for 64.42% of variance observed. Convergent validity was mostly supported by the pattern of association between the Seattle angina questionnaire-Farsi version and the SF-36. Cronbach’s alpha of the subscales ranged from 0.60 to 0.86 and test-retest scores ranged from 0.79 to 0.97 indicating a good range of reliability.

Conclusions

The Seattle angina questionnaire-Farsi version had acceptable psychometric properties. Therefore, it can be used to assess health-related quality of life and assess the effects of different medical and nursing interventions on patients’ quality of life.

     

Development and initial psychometric evaluation of the hepatitis C virus-patient-reported outcomes (HCV-PRO) instrument

Background

Chronic hepatitis C virus (HCV) infection is an important public health issue owing to its worldwide prevalence and its profound effects on patients’ well-being and function. We developed a new patient self-report tool, the HCV patient-reported outcomes (HCV-PRO) instrument, to assess patients’ function and well-being reflecting both HCV disease and treatment burdens.

Methods

Items were developed through a qualitative phase including scientific literature review, expert appraisal, and semi-structured patient interviews. The item pool was initially psychometrically tested in 60 adult HCV patients, 18 years of age or older at a university hepatology clinic. A final psychometric test was conducted in 241 members of the online Harris International Panel to examine scale reliability, confirm factor structure, and assess convergent and discriminant validity.

Results

A single-factor 16-item HCV-PRO instrument demonstrated good model fit. The HCV-PRO items and total score (range 0–100) showed excellent item response (few floor and ceiling effects) and reliability (alpha > 0.90). Convergent validity was established from moderate to high (r > 0.50) correlation with symptom burden, life satisfaction (ladder of life), and SF-36v2 scales scores. Mean HCV-PRO scores differentiated between currently treated patients, those previously treated, and patients never treated (p < 0.01), suggesting strong known-groups validity.

Conclusions

The results provide initial evidence that the HCV-PRO can yield reliable and valid measurement of the effects of HCV and its treatment on the well-being and function of HCV-infected patients.     

Measurement bias of the SF-36 Health Survey in older adults with chronic conditions

Purpose

The objectives of this study were to investigate the psychometric properties of the SF-36 in a sample of older adults with chronic conditions and to test whether measurement bias exists based on the levels of comorbidity.

Methods

Participants included were 979 cognitively intact older adults with comorbidities who were interviewed at their homes. We examined the psychometric properties of the SF-36 and conducted confirmatory factor analysis (CFA) to investigate the assumption of measurement invariance by the levels of comorbidity.

Results

Overall data quality was high and scaling assumptions were generally met with few exceptions. Floor and ceiling effects were present for the role-physical and role-emotional subscales. Using CFA, we found that a three-factor measurement model fits the data well. We identified two violations of measurement invariance. Results showed that participants with high comorbidity level place more emphasis on social functioning (SF) and bodily pain (BP) in relation to physical health-related quality of life (HRQoL) than those with low comorbidity level.

Conclusions

Measurement bias was present for the SF and BP components of the SF-36 physical HRQoL measure. Researchers should be cautious when considering the use of SF-36 in clinical studies among older adults with comorbidities.     

Validity and reliability of the Chinese version of the Short Form of Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q-SF)

Purpose

The Short Form version of the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q-SF) was designed to measure patients’ subjective experience of enjoyment and satisfaction. However, it had not yet been validated for Chinese societies. This paper reports on the validation of the Chinese version of the Q-LES-Q-SF among primary care patients in Taiwan.

Methods

The study included adult patients in primary care clinics. The participants completed the Q-LES-Q-SF, the Patient Health Questionnaire, and the Short Form Health Survey. After that, the trained researchers interviewed the patients using the mood module of the Schedules for Clinical Assessment in Neuropsychiatry and the 17-item Hamilton Rating Scale for Depression. A subsample of participants was reassessed with Q-LES-Q-SF within a 2-week interval.

Results

A total of 1,482 patients completed the Q-LES-Q-SF. The content validity was good, with no significant floor/ceiling effect. The internal consistency of the Q-LES-Q-SF proved to be substantial as well as the test–retest reliability. The factor structure was examined by exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The EFA yielded a 2-factor structure, which was confirmed by a CFA with acceptable fit indices. Known-group validity of the Q-LES-Q-SF was satisfactory in distinguishing patients with and without depression, according to hierarchical regression analyses. Evidence of concurrent validity was provided for the Q-LES-Q-SF, and its two subscales identified significant correlations with other measures.

Conclusion

The Chinese Q-LES-Q-SF was shown to have adequate validity and reliability. It may be a useful tool to measure patients’ quality of life in Chinese societies.     

Assessment of the Dermatology Life Quality Index (DLQI) in a homogeneous population under lifetime arsenic exposure

Purpose

The psychometric property of the Dermatology Life Quality Index (DLQI) is underappreciated in public health settings. Our study aimed to assess the reliability, validity, and measurement invariance of DLQI in a homogeneous population with arsenic-related skin lesions and symptoms.

Methods

A cross-sectional study was conducted in communities under lifetime arsenic exposure. The DLQI was measured through a face-to-face interview. Skin examinations were performed by certificated dermatologists. The intensity of itching was measured by a numerical rating scale. Reliability, structural validity, and measurement invariance were determined using classical and modern test theories, including confirmatory factor analysis and item response models.

Results

465 participants with arsenic-related skin lesions and symptoms completed the DLQI assessment. The Cronbach’s alpha was 0.79, and the split-half reliability was 0.77. A two-factor model exhibited the best model fit among models evaluated, but local dependencies among items were identified. The model showed good root mean square error of approximation (0.031) and acceptable Tucker–Lewis index (0.92). Multi-group confirmatory factor analysis showed no measurement invariance across subgroups of age, gender, ethnicity, and intensity of itching.

Conclusions

The DLQI had acceptable psychometric properties, but measurement invariance was not observed across different groups of participants.

     

Exploring psychometric properties of the SF-6D,a preference-based health-related quality of life measure,in the context of spinal cord injury

Purpose

The validity of the SF-6D, a preference-based measure of health-related quality of life, is not well explored in the context of spinal cord injury (SCI). The aim of this analysis was to assess appropriate measurement properties of the SF-6D in a sample of individuals living with SCI.

Methods

Longitudinal data from the Rick Hansen Spinal Cord Injury Registry were used. Responses to the 36-item short-form health survey were transformed into SF-6D utility scores. We investigated practicality, floor and ceiling effects, and responsiveness to change. Responsiveness to change was explored using three different anchors that reflected changes in self-reported health, functional independence, and life satisfaction. Discriminative validity was assessed by ten a priori defined hypotheses, with a distinction made between ‘strong’ and ‘weak’ hypotheses.

Results

Three hundred and fifty-eight individuals with SCI were included in this analysis. Practicality was deemed acceptable based on a completion rate of 94 %. The SF-6D showed low responsiveness to detect important health changes over time, and differences in responsiveness were found between individuals with paraplegia and tetraplegia. All five strong hypotheses and three weak hypotheses were confirmed.

Conclusion

The SF-6D demonstrated good practicality and discriminative validity in this sample. The failure to detect self-reported and clinically important health changes requires further consideration. Comparative performance of the SF-6D (i.e., how the SF-6D performs against other preference-based measures) is unknown in the SCI context and requires further research.     

Preliminary reliability and validity of Persian version of the Family Dermatology Life Quality Index (FDLQI)

Purpose

Family Dermatology Life Quality Index (FDLQI) is an instrument for assessing the quality of life of family members of dermatologic patients. The aim of this study was to describe the cultural adaptation of this questionnaire and to assess psychometric properties of the Persian version.

Methods

At first, the questionnaire was translated into Persian, and then back-translation was performed. The whole cycle was repeated until a consensus was reached about the optimal translation. In the next step, cognitive debriefing was performed, and after approval of the Persian version by FDLQI developers, it was distributed among 100 family members of dermatological patients in order to evaluate its validity and reliability.

Results

Mean age of participants was 37.1 years (±12.3). Mean score of FDLQI was 15.4 (±5.5) with maximum and minimum scores of 30 and 6, respectively. The quality of life of studied participants showed no significant difference based on age-group, sex, educational level and the family relationship. Cronbach’s alpha was calculated as 0.87. Exploratory factor analysis revealed a one-factor solution that accounted for 40.7 % of the variance. The unidimensional model was supported by confirmatory factor analysis.

Conclusions

The results of the present study showed that the Persian version of FDLQI has acceptable factorial validity and internal consistency reliability.