To determine whether community integration and/or quality of life (QoL) among people living with chronic spinal cord injury (SCI) are superior among sport participants vs non-sport participants.
Persons (n = 90) living in the community with SCI (ASIA Impairment Scale A–D), level C5 or below, > 15 years of age, ≥ 12 months postinjury, and requiring a wheelchair for > 1 hours/day were divided into 2 groups based on their self-reported sport participation at interview: sport participants (n = 45) and non-sport participants (n = 45).
Independent-sample t tests revealed that both Community Integration Questionnaire (CIQ) and Reintegration to Normal Living Index (RNL) total mean scores were higher among sport participants vs non-sport participants (P < 0.05). Significant correlation between CIQ and RNL total scores was found for all participants (Pearson correlation coefficients, P < 0.01). Logistic regression analysis revealed that the unadjusted odds ratio of a high CIQ mean score was 4.75 (95% CI 1.7, 13.5) among current sport participants. Similarly, the unadjusted odds ratio of a high RNL score was 7.00 (95% CI 2.3, 21.0) among current sport participants. Regression-adjusted odds ratios of high CIQ and high RNL scores were 1.36 (95% CI 0.09, 1.45) and 0.15 (95% CI 0.04, 0.55), respectively. The odds ratio for pre-SCI sport participation predicting post-SCI sport participation was 3.06 (95% CI 1.23, 7.65).
CIQ and QoL scores were higher among sport participants compared to non-sport participants. There was an association between mean CIQ and RNL scores for both groups. Sport participants were 4.75 and 7.00 times as likely to have high CIQ and QoL scores. Both groups had a similar likelihood of high CIQ and RNL scores after adjusting for important confounders. Individuals who participated in sports prior to SCI were more likely to participate in sports post-SCI.
Spinal cord injuries; Tetraplegia; Paraplegia; Disability; Sport participation; Wheelchair sports; Community reintegration; Quality of life
The objective of our study was to assess the psychometric properties of the Medical Outcomes Study's 12-Item Short Form Survey Instrument (SF-12) for use in a low-income African American community. The SF-12, a commonly used functional health status assessment, was developed based on responses of an ethnically homogeneous sample of whites. Our assessment addressed the appropriateness of the instrument for establishing baseline indicators for mental and physical health status as part of Nashville, Tennessee's, Racial and Ethnic Approaches to Community Health (REACH) 2010 initiative, a community-based participatory research study.
A cross-sectional random residential sample of 1721 African Americans responded to a telephone survey that included the SF-12 survey items and other indicators of mental and physical health status. The SF-12 was assessed by examining item-level characteristics, estimates of scale reliability (internal consistency), and construct validity.
Construct validity assessed by the method of extreme groups determined that SF-12 summary scores varied for individuals who differed in self-reported medical conditions. Convergent and discriminate validity assessed by multitrait analysis yielded satisfactory coefficients. Concurrent validity was also shown to be satisfactory, assessed by correlating SF-12 summary scores with independent measures of physical and mental health status.
The SF-12 appears to be a valid measure for assessing health status of low-income African Americans.
Purpose: To further investigate the construct validity of the Community Balance and Mobility Scale (CB&M), developed for ambulatory individuals with traumatic brain injury (TBI).
Methods: A convenience sample of 35 patients with TBI (13 in-patients, 22 outpatients) was recruited. Analyses included a comparison of CB&M and Berg Balance Scale (BBS) admission and change scores and associations between the CB&M and measures of postural sway, gait, and dynamic stability; the Community Integration Questionnaire (CIQ); and the Activities-specific Balance Confidence (ABC) Scale.
Results: Mean admission scores on the BBS and the CB&M were 53.6/56 (SD=4.3) and 57.8/96 (SD=23.3) respectively. Significant correlations were demonstrated between the CB&M and spatiotemporal measures of gait, including walking velocity, step length, step width, and step time; measures of dynamic stability, including variability in step length and step time; and the ABC (p<0.05). Significant correlations between the CB&M and CIQ were revealed with a larger data set (n=47 outpatients) combined from previous phases of research.
Conclusions: In patients with TBI, the CB&M is less susceptible to a ceiling effect than the BBS. The construct validity of the CB&M was supported, demonstrating associations with laboratory measures of dynamic stability, measures of community integration, and balance confidence.
balance; brain injuries; posture; mobility limitations; outcome assessment; équilibre; évaluation des résultats; limites à la mobilité; posture; traumatisme crânien
Health is defined as the state of complete physical, mental and social well-being than just the absence of disease or infirmity. In order to measure health in the community, a reliable and validated instrument is required.
To adapt and translate the Medical Outcomes Study Short-Form Health Survey (SF-36) for use in India, to study its validity and reliability and to explore its higher order factor structure.
Materials and Methods:
Face-to-face interviews were conducted in 184 adult subjects by two trained interviewers. Statistical analyses for establishing item-level validity, scale-level validity and reliability and tests of known group comparison were performed. The higher order factor structure was investigated using principal component analysis with varimax rotation.
The questionnaire was well understood by the respondents. Item-level validity was established using tests of item internal consistency, equality of item-scale correlations and item-discriminant validity. Tests of scale-level validity and reliability performed well as all the scales met the required internal consistency criteria. Tests of known group comparison discriminated well across groups differing in socio-demographic and clinical variables. The higher order factor structure was found to comprise of two factors, with factor loadings being similar to those observed in other Asian countries.
The item-and scale-level statistical analyses supported the validity and reliability of SF-36 for use in India.
Health surveys; reliability; questionnaires; quality of life; translations; validity
The Manchester Foot Pain and Disability Index (MFPDI) is a 19 item questionnaire used to assess the severity and impact of foot pain. The aim of this study was to develop a Greek-language version of the MFPDI and to assess the instrument's psychometric properties.
The MFPDI was translated into Greek by three bilingual content experts and two bilingual language experts, and then back-translated into English to assess for equivalence. The final Greek version was administered, along with a questionnaire consisting medical history and the Medical Outcomes Study Short Form 36 (SF-36), to 104 Greek-speaking, community-dwelling people (64 female, 40 male), aged between 64 and 90 years (mean 73.00, SD 5.26) with disabling foot pain.
The Greek translation of the MFPDI was found to have high internal consistency (Cronbach's α= 0.89, and item-total correlation coefficients from 0.33 to 0.72). Principal components analysis revealed a four-factor structure representing the constructs of functional limitation, pain intensity, concern with appearance and activity restriction, which explained 60.8% of the variance, with 38.9% of the variance explained by the first construct (functional limitation). Six items demonstrated different factor loadings to the original English version.
The Greek-language version of the MFPDI appears to be a valid tool in assessing foot pain in Greek-speaking older people. The total MFPDI scores are comparable between the Greek and English version, however due to differences in the factor loadings of some items, between-language comparisons of MFPDI should be undertaken with some caution.
Purpose: The purposes of these studies were to develop and initially evaluate the psychometric properties of the Reasons for Living Scale—Older Adult version (RFL-OA), an older adults version of a measure designed to assess reasons for living among individuals at risk for suicide. Design and Methods: Two studies are reported. Study 1 involved instrument development with 106 community-dwelling older adults, and initial psychometric evaluation with a second sample of 119 community-dwelling older adults. Study 2 evaluated the psychometric properties of the RFL-OA in a clinical sample. One hundred eighty-one mental health patients 50 years or older completed the RFL-OA and measures of depression, suicide ideation at the current time and at the worst point in one's life, and current mental status and physical functioning. Results: Strong psychometric properties were demonstrated for the RFL-OA, with high internal consistency (Cronbach's alpha coefficient). Convergent validity was evidenced by negative associations among RFL-OA scores and measures of depression and suicide ideation. RFL-OA scores predicted current and worst-episode suicide ideation above and beyond current depression. Discriminant validity was evidenced with measures of current mental status and physical functioning. Criterion-related validity was also demonstrated with respect to lifetime history of suicidal behavior. Implications: These findings provide preliminary support for the validity and reliability of the RFL-OA. The findings also support the potential value of attending to reasons for living during clinical treatment with depressed older adults and others at risk for suicide.
Suicide; Reasons for living; Suicide risk; Resilience
To examine if activity limitation differs between 2 low back pain (LBP) subgroups in the Movement System Impairment (MSI) model.
Cross-sectional observational study.
University medical center musculoskeletal analysis laboratory.
Convenience sample of 83 subjects with chronic LBP who were subgrouped as rotation (Rot) or rotation with extension (RotExt) according to the MSI model.
Main Outcome Measurements
Subjects completed the modified Oswestry Low Back Pain Disability Questionnaire and the physical function subscale of the 36-Item Short-Form Health survey (SF-36 PFS) to assess activity limitation. Subjects also completed baseline measures related to demographics, LBP history, pain intensity, habitual activity level, general health status, and fear-avoidance behavior. Independent-samples t-tests, χ2 tests of independence, and 2-way analysis of variance tests were used to analyze the data.
Subjects in the Rot subgroup reported greater activity limitation on the modified Oswestry Questionnaire (P = .02) and SF-36 PFS (P = .03) than subjects in the RotExt subgroup. No other differences between LBP subgroups were significant (P > .05), except gender. More women (71%) than men (29%) were in the RotExt subgroup (P = .03). However, there was no main effect of gender and no interaction effect of gender and LBP subgroup on the modified Oswestry Questionnaire or the SF-36 PFS (P > .05).
These results support that the Rot and RotExt LBP subgroups based on the MSI model differ with regard to variables that index activity limitation, with the Rot subgroup reporting greater limitation on both activity limitation measures. These differences are not the result of differences in other baseline measures.
There currently exists no reliable or validated tool for the assessment of exercise-related injuries in older adults. The purpose was to develop and evaluate the psychometric properties of a questionnaire to measure exercise-related injury in older adults participating in supervised exercise programmes.
The study utilised a repeated survey design.
The study took place at one community-based older-adult exercise facility.
The questionnaire was administered to 110 community-dwelling older adults (45 men, mean age 75±8 years; 65 women, mean age 71±8 years). All participants completed the survey at both time points.
Test–retest reliability of the self-administered written questionnaire was determined at two-time points. The questionnaire asked participants about their exercise-related injury incurred at the facility in the 12 months. Items included the mechanism, cause and site of injury. The minimum requirement for reliability (κ coefficient) was set at 0.80.
16% (n=18) reported having an injury. Test–retest reliability ranged from 0.76 to 1.00, with all but type of injury (0.76) having κ coefficients greater than 0.80. The lower extremities were the most common site of exercise-related injury. Overexertion movements were the most common cause of injury occurring during strength training exercises.
The present questionnaire assessing the 12-month recall in older adults is a reliable measure of exercise-related injuries and information gained indicates that older adults can safely participate in exercise activities.
Epidemiology; Sports Medicine; Statistics & Research Methods
Depression worsens outcomes of physical illness. However, it is unknown whether this negative effect persists after depressive symptoms remit in older adults. This study examined whether prior depression history predicts deterioration of physical health in community-dwelling older adults.
Prospective cohort study
Three urban communities in the United States
351 adults aged 60 or older – 145 with a history of major or non-major depression in full remission and 206 concurrent age- and gender-matched comparison subjects with no history of mental illness.
Participants were assessed at baseline, 6 weeks, 1 year and 2 years for physical health functioning (the Physical Component Summary of the 36-Item Short-Form Health Survey) and chronic medical burden (the Chronic Disease Score). Given the repeated nature of measurements, linear mixed model regression was performed.
Both physical functioning and chronic medical burden deteriorated more rapidly over time in the group with prior depression history compared to comparison subjects, and these changes were independent of the measures of mental health functioning, depressive symptoms and sleep quality. Similar results were observed when those who developed depressive episodes during follow-up were excluded.
A prior history of clinical depression is associated with a faster deterioration of physical health in community-dwelling older adults, which is not explained by current levels of depressive symptoms and mental health functioning, nor by recurrence of depressive episodes. Careful screening for a past history of depression may identify those older adults at greatest risk for physical declines and chronic medical burden.
prior depression history; physical health; older adults
Self-perceptions of aging have been implicated as independent predictors of functional disability and mortality in older adults. In spite of this, research on self-perceptions of aging is limited. One reason for this is the absence of adequate measures. Specifically, there is a need to develop a measure that is theoretically-derived, has good psychometric properties, and is multidimensional in nature. The present research seeks to address this need by adopting the Self-Regulation Model as a framework and using it to develop a comprehensive, multi-dimensional instrument for assessing self-perceptions of aging. This study describes the validation of this newly-developed instrument, the Aging Perceptions Questionnaire (APQ).
Participants were 2,033 randomly selected community-dwelling older (+65 yrs) Irish adults who completed the APQ alongside measures of physical and psychological health. The APQ assesses self-perceptions of aging along eight distinct domains or subscales; seven of these examine views about own aging, these are: timeline chronic, timeline cyclical, consequences positive, consequences negative, control positive, control negative, and emotional representations; the eighth domain is the identity domain and this examines the experience of health-related changes.
Mokken scale analysis showed that the majority of items within the views about aging subscales were strongly scalable. Confirmatory factor analysis also indicated that the model provided a good fit for the data. Overall, subscales had good internal reliabilities. Hierarchical linear regression was conducted to investigate the independent contribution of APQ subscales to physical and psychological health and in doing so determine the construct validity of the APQ. Results showed that self-perceptions of aging were independently related to physical and psychological health. Mediation testing also supported a role for self-perceptions of aging as partial mediators in the relationship between indices of physical functioning and physical and psychological health outcomes.
Findings support the complex and multifaceted nature of the aging experience. The good internal reliability and construct validity of the subscales suggests that the APQ is a promising instrument that can enable a theoretically informed, multidimensional assessment of self-perceptions of aging. The potential role of self-perceptions of aging in facilitating physical and psychological health in later life is also highlighted.
Symptom-based surveys suggest that the prevalence of gastrointestinal diseases is lower in China than in Western countries. The aim of this study was to validate a methodology for the epidemiological investigation of gastrointestinal symptoms and endoscopic findings in China.
A randomized, stratified, multi-stage sampling methodology was used to select 18 000 adults aged 18-80 years from Shanghai, Beijing, Xi'an, Wuhan and Guangzhou. Participants from Shanghai were invited to provide blood samples and undergo upper gastrointestinal endoscopy. All participants completed Chinese versions of the Reflux Disease Questionnaire (RDQ) and the modified Rome II questionnaire; 20% were also invited to complete the 36-item Short Form Health Survey (SF-36) and Epworth Sleepiness Scale (ESS). The psychometric properties of the questionnaires were evaluated statistically.
The study was completed by 16 091 individuals (response rate: 89.4%), with 3219 (89.4% of those invited) completing the SF-36 and ESS. All 3153 participants in Shanghai provided blood samples and 1030 (32.7%) underwent endoscopy. Cronbach's alpha coefficients were 0.89, 0.89, 0.80 and 0.91, respectively, for the RDQ, modified Rome II questionnaire, ESS and SF-36, supporting internal consistency. Factor analysis supported construct validity of all questionnaire dimensions except SF-36 psychosocial dimensions.
This population-based study has great potential to characterize the relationship between gastrointestinal symptoms and endoscopic findings in China.
Purpose: This cross-sectional study explores the psychometric properties and dimensionality of the Fullerton Advanced Balance (FAB) Scale, a multi-item balance test for higher-functioning older adults.
Methods: Participants (n=480) were community-dwelling adults able to ambulate independently. Data gathering consisted of survey and balance performance assessment. Psychometric properties were assessed using Rasch analysis.
Results: Mean age of participants was 76.4 (SD=7.1) years. Mean FAB Scale scores were 24.7/40 (SD=7.5). Analyses for scale dimensionality showed that 9 of the 10 items fit a unidimensional measure of balance. Item 10 (Reactive Postural Control) did not fit the model. The reliability of the scale to separate persons was 0.81 out of 1.00; the reliability of the scale to separate items in terms of their difficulty was 0.99 out of 1.00. Cronbach's alpha for a 10-item model was 0.805. Items of differing difficulties formed a useful ordinal hierarchy for scaling patterns of expected balance ability scoring for a normative population.
Conclusion: The FAB Scale appears to be a reliable and valid tool to assess balance function in higher-functioning older adults. The test was found to discriminate among participants of varying balance abilities. Further exploration of concurrent validity of Rasch-generated expected item scoring patterns should be undertaken to determine the test's diagnostic and prescriptive utility.
aged; balance; fall risk assessment tool; falls; psychometrics; FAB Scale; aînés; chutes; équilibre; outil d'évaluation du risque de chute; psychométrie
The WHODAS-II was substantially modified for use in the World Mental Health Surveys. This paper considers the modified WHODAS-II’s psychometric properties and implications of filter items employed to reduce respondent burden.
Study design and setting
Seventeen surveys in 16 countries administered a modified WHODAS-II to population samples (N=38,934 adults). Modifications included introducing filter questions for four sub-scales and substituting questions on the number of days activity was limited for the Life Activities domain. We evaluated distributional properties, reliability, and validity of the modified WHODAS-II.
Most respondents (77%–99%) had zero scores on filtered subscales. Lower bound estimates of internal consistency (alpha) for the filtered subscales were typically in the 0.70’s, but were higher for the Global scale. Loadings of subscale scores on a Global Disability factor were moderate-to-high. Correlations with the Sheehan Disability Scale were modest but consistently positive, while correlations with SF-12 Physical Component Summary were considerably higher. Cross-national variability in disability scores was observed, but was not readily explainable.
Internal consistency and validity of the modified WHODAS-II was generally supported, but use of filter questions impaired measurement properties. Group differences in modified WHODAS-II disability scores may be compared within, but not necessarily across, countries.
Disability; Measurement; Reliability; Validity; Survey; Epidemiology
Effective communication skills and professionalism are critical for physicians in order to provide optimum care and achieve better health outcomes. The aims of this study were to evaluate residents' self-assessment of their communication skills and professionalism in dealing with patients, and to evaluate the psychometric properties of a self-assessment questionnaire.
A modified version of the American Board of Internal Medicine's (ABIM) Patient Assessment survey was completed by 130 residents in 23 surgical and non-surgical training programs affiliated with a single medical school. Descriptive, regression and factor analyses were performed. Internal consistency, inter-item gamma scores, and discriminative validity of the questionnaire were determined.
Factor analysis suggested two groups of items: one group relating to developing interpersonal relationships with patients and one group relating to conveying medical information to patients. Cronbach's alpha (0.86) indicated internal consistency. Males rated themselves higher than females in items related to explaining things to patients. When compared to graduates of U.S. medical schools, graduates of medical schools outside the U.S. rated themselves higher in items related to listening to the patient, yet lower in using understandable language. Surgical residents rated themselves higher than non-surgical residents in explaining options to patients.
This appears to be an internally consistent and reliable tool for residents' self-assessment of communication skills and professionalism. Some demographic differences in self-perceived communication skills were noted.
Many clinical trials comparing the outcomes of open surgical repair (OSR) versus endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAAs) have been conducted, with varying results. Surprisingly, few outcomes studies have closely examined perceived physical and mental health-related quality of life (HRQOL) factors through a validated survey tool. The purpose of this prospective observational study was to describe the trajectory of HRQOL measures, from baseline to 1 year after surgery, in patients undergoing OSR or EVAR for AAA, and to explore for differences in physical and mental composite scores and their construct domains (subscales) using the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36®) tool.
Patients and methods
Over an 18-month period, a small sample of patients undergoing elective AAA repair in a community hospital setting were prospectively enrolled. Fifteen patients undergoing OSR and twenty patients undergoing EVAR were studied. Physical and mental HRQOL parameters were assessed using the SF-36.
No significant differences in demographic and clinical variables were found between the OSR and EVAR groups. In the multivariable linear models with repeated measures, both groups showed a significant decline in physical health composite scores 30 days after the surgical procedure (P < 0.01). However, although the OSR group showed a statistically significant decline in three of the four physical health domains, the EVAR group declined in only one physical health domain. Only the OSR group showed a significant decline in three of the four mental health domains at 30 days; however, the decline of these domains was not reflected in the group’s mental health composite scores. By 90 days after surgery, both groups were not significantly different from their baseline in physical or mental health composite scores, or in any of their respective physical health domains.
In this small sample of patients undergoing AAA repair, EVAR resulted in less physical and emotional decline than OSR in the early postoperative period. However, patients in both groups may return to near baseline status at 90 days.
AAA; endovascular aneurysm repair (EVAR); open surgical repair (OSR); Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36®); health related quality of life (HRQ)
The Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) and the Medical Outcomes Study Short Form 36 (SF-36) are widely used to assess patient-reported outcome in individuals with pulmonary hypertension (PH). The aim of the study was to compare the psychometric properties of the two measures.
Participants were recruited from specialist PH centres in Australia and New Zealand. Participants completed the CAMPHOR and SF-36 at two time points two weeks apart. The SF-36 is a generic health status questionnaire consisting of 36 items split into 8 sections. The CAMPHOR is a PH-specific measure consisting of 3 scales; symptoms, activity limitations and needs-based QoL. The questionnaires were assessed for distributional properties (floor and ceiling effects), internal consistency (Cronbach's alpha), test-retest reliability and construct validity (scores by World Health Organisation functional classification).
The sample comprised 65 participants (mean (SD) age = 57.2 (14.5) years; n(%) male = 14 (21.5%)). Most of the patients were in WHO class 2 (27.7%) and 3 (61.5%). High ceiling effects were observed for the SF-36 bodily pain, social functioning and role emotional domains. Test-retest reliability was poor for six of the eight SF-36 domains, indicating high levels of random measurement error. Three of the SF-36 domains did not distinguish between WHO classes. In contrast, all CAMPHOR scales exhibited good distributional properties, test retest reliability and distinguished between WHO functional classes.
The CAMPHOR exhibited superior psychometric properties, compared with the SF-36, in the assessment of PH patient-reported outcome.
To (1) describe the relationship between symptom scores and mobility function measures, (2) assess whether symptom scores and disease scores are similarly associated with mobility function, and (3) identify clusters of symptoms that are most strongly associated with functional status in older adults
Secondary analysis of cross-sectional data from three cohorts
Academic medical center
195 community-dwelling subjects with poor flexibility or cardiorespiratory fitness (fitness cohort), 211 female retirement community residents with vertebral fractures (VF cohort), and 61 subjects with Parkinson's disease (PD cohort)
20-item self-reported symptom scale, 17-item self-reported disease scale, Short Form 36 (SF-36) Physical Functioning Scale, 5-item Nagi Disability scale, 10-meter walk time, supine to stand time
Symptom scores correlated with mobility function measures (Spearman correlation coefficients range from 0.222 to 0.509) at least as strongly as, if not more strongly than did disease scores. Symptom scores remained associated with functional outcomes after controlling for disease score and demographic variables. Adding symptom scores to models that contained disease scores significantly increased the association with functional outcomes. In the fitness cohort, muscle weakness was the most explanatory single symptom, associated with an average decrease of 17.8 points on the Physical Functioning Scale. A model that included only muscle weakness, pain, and shortness of breath accounted for 21.2% of the variability in the Physical Functioning Score.
Symptoms represent useful indicators of disability burden in older adults and are promising targets for interventions to improve function in complex patients.
symptom; function; disability; comorbidity
Objective: The 36-Item Short Form Health Survey (SF-36) is widely validated and popularly used in assessing the subjective quality of life (QOL) of patients and the general public. The aim of the study is to assess the psychometric properties of the 36-Item Short Form Health Survey (SF-36) in medical students in mainland of China.
Methods: The reliability and validity of the 36-Item Short Form Health Survey (SF-36) questionnaire were assessed by conducting a cross-sectional study of Chinese medical students in December 2011. All 1358 3rd year and 4th year medical students from 46 classes at China Medical University were investigated.
Results: The overall Cronbach's α coefficient of the SF-36 questionnaire was 0.791, while the respective Cronbach's α coefficients for each of the seven dimensions were > 0.70, except where the social function dimension was 0.631. Results showed that the SF-36 questionnaire was reliable and valid.
Conclusion: In general, this study provides evidence that the SF-36 questionnaire is suitable measures for assess the QOL of medical students in China.
Medical student; Quality of life; The 36-item short form health survey (SF-36); Reliability; Validity.
Previous studies have analyzed the psychometric properties of the World Health Organization Disability Assessment Schedule II (WHO-DAS II) using classical omnibus measures of scale quality. These analyses are sample dependent and do not model item responses as a function of the underlying trait level. The main objective of this study was to examine the effectiveness of the WHO-DAS II items and their options in discriminating between changes in the underlying disability level by means of item response analyses. We also explored differential item functioning (DIF) in men and women.
The participants were 3615 adult general practice patients from 17 regions of Spain, with a first diagnosed major depressive episode. The 12-item WHO-DAS II was administered by the general practitioners during the consultation. We used a non-parametric item response method (Kernel-Smoothing) implemented with the TestGraf software to examine the effectiveness of each item (item characteristic curves) and their options (option characteristic curves) in discriminating between changes in the underliying disability level. We examined composite DIF to know whether women had a higher probability than men of endorsing each item.
Item response analyses indicated that the twelve items forming the WHO-DAS II perform very well. All items were determined to provide good discrimination across varying standardized levels of the trait. The items also had option characteristic curves that showed good discrimination, given that each increasing option became more likely than the previous as a function of increasing trait level. No gender-related DIF was found on any of the items.
All WHO-DAS II items were very good at assessing overall disability. Our results supported the appropriateness of the weights assigned to response option categories and showed an absence of gender differences in item functioning.
Sleep is an important element of functioning and well-being. The Medical Outcomes Study Sleep Scale (MOS-Sleep) includes 12 items assessing sleep disturbance, sleep adequacy, somnolence, quantity of sleep, snoring, and awakening short of breath or with a headache. A sleep problems index, grouping items from each of the former domains, is also available. This study evaluates the psychometric properties of MOS-Sleep Scale in a painful diabetic peripheral neuropathic population based on a clinical trial conducted in six countries.
Clinical data and health-related quality of life data were collected at baseline and after 12 weeks of follow-up. Overall, 396 patients were included in the analysis. Psychometric properties of the MOS-Sleep were assessed in the overall population and per country when the sample size was sufficient. Internal consistency reliability was assessed by Cronbach's alpha; the structure of the instrument was assessed by verifying item convergent and discriminant criteria; construct validity was evaluated by examining the relationships between MOS-Sleep scores and sleep interference and pain scores, and SF-36 scores; effect-sizes were used to assess the MOS-Sleep responsiveness. The study was conducted in compliance with United States Food and Drug Administration regulations for informed consent and protection of patient rights.
Cronbach's alpha ranged from 0.71 to 0.81 for the multi-item dimensions and the sleep problems index. Item convergent and discriminant criteria were satisfied with item-scale correlations for hypothesized dimensions higher than 0.40 and tending to exceed the correlations of items with other dimensions, respectively. Taken individually, German, Polish and English language versions had good internal consistency reliability and dimension structure. Construct validity was supported with lower sleep adequacy score and greater sleep problems index scores associated with measures of sleep interference and pain scores. In addition, correlations between the SF-36 scores and the MOS-Sleep scores were low to moderate, ranging from -0.28 to -0.53. Responsiveness was supported by effect sizes > 0.80 for patients who improved according to the mean sleep interference and pain scores and clinician and patient global impression of change (p < 0.0001).
The MOS-Sleep had good psychometric properties in this painful diabetic peripheral neuropathic population.
As this study was conducted from 2000 to 2002 (i.e., before the filing requirement came out), no trial registration number is available.
Studies that compare health-related quality of life (HRQOL) and other patient-reported outcomes in different populations rest on the assumption that the measure has equivalent psychometric properties across groups. This study examined the measurement equivalence (ME) of the 36-item Medical Outcomes Study Short Form Survey (SF-36), a widely-used measure of HRQOL, by sex and race in a population-based Canadian sample.
SF-36 data were from the Canadian Multicentre Osteoporosis Study, a prospective cohort study that randomly sampled adult men and women from nine sites across Canada. Confirmatory factor analysis (CFA) techniques were used to test hypotheses about four forms of ME, which are based on equality of the factor loadings, variances, covariances, and intercepts. Analyses were conducted for Caucasian and non-Caucasian females (n = 6,539) and males (n = 2,884). CFA results revealed that a measurement model with physical and mental health factors provided a good fit to the data. All forms of ME were satisfied for the study groups.
The results suggest that sex and race do not influence the conceptualization of a general measure of HRQOL in the Canadian population.
SF-36; Health-related quality of life; Psychometrics; Equivalence; Confirmatory factor analysis
The short version of the World Health Organization's Quality of Life Instrument (WHOQOL-BREF) is widely validated and popularly used in assessing the subjective quality of life (QOL) of patients and the general public. We examined its psychometric properties in a large sample of community residents in mainland China.
The WHOQOL-BREF was administered to 1052 adult community residents in a major metropolitan city in southern China. The structural integrity of the 4-factor model in confirmatory factor analyses (CFA) and the relationship of QOL with demographic variables were examined. Validity was assessed using the known-group comparison (229 with vs. 823 without chronic illness), item-domain correlations, and CFA using the ML estimation in LISREL.
Internal consistency reliability of the whole instrument (26 items) was 0.89, and the psychological, social, and environment domains had acceptable reliability (alpha = 0.76, 0.72, 0.78 respectively), while that of the physical domain was slightly lower (α = 0.67). The respective mean scores of these domains were 13.69, 14.11, 12.33 and 14.56. Item-domain correlations were much higher for corresponding domains than for non-corresponding domains, indicating good convergent validity. CFA provided a marginally acceptable fit to the a priori four-factor model when two matching content item pairs were allowed to be correlated; χ2 (244) = 1836, RMSEA = 0.088, NNFI = 0.898, CFI = 0.909. This factorial structure was shown to be equivalent between the participants with and without chronic illness. The differences in means between these two groups were significant but small in some domains; effect size = 0.55, 0.15, 0.18 in the physical, psychological, and social relationship domains respectively. Furthermore, males had significantly higher QOL scores than females in the psychological domain, while individuals with a younger age, higher income, and higher education levels also had significantly higher QOL. Compared with the international data, the Chinese in this study had relatively low QOL scores with about 5% of males and 16% of females being at risk for poor QOL.
This study has provided psychometric properties of the WHOQOL-BREF as used in China and should definitely be useful for researchers who would like to use or further refine the instrument.
Differential item functioning (DIF) assesses the consistency of items on a metric across clinical samples in relation to the attribute being measured. We hypothesized that in older adults with persistent pain, items of the Geriatric Depression Scale (GDS) would evidence DIF based on presence or intensity of pain.
Unidimensionality was determined by factor and item analyses. DIF was tested using Rasch Modeling. We then evaluated the psychometric properties of a revised GDS (GDS-PAIN), comprised of items that did not evidence DIF.
Patient and Settings
A total of 677 community dwelling older adults (age 65–91) participating in observational or treatment studies of low back or knee pain who endorsed at least moderate pain for at least 3 months. A total of 201 pain-free controls were included in the analysis.
Ten of the 30 items displayed significant DIF. These items were: 1) dropping activities and interests; 2) bothered by persistent thoughts; 3) often get fidgety and restless; 4) prefer to stay home; 5) do not feel full of energy; 6) do not enjoy getting up in the morning; 7) mind is not as clear as it was, 8) feel life is empty; 9) feel more problems with memory; and 10) do not find life very exciting. The modified GDS-PAIN scale did not adversely affect the psychometric properties of the scale.
The performance of the GDS is affected by pain. When unstable items are removed, the revised GDS (GDS-PAIN) appears to be psychometrically stable and maintains both internal consistency and similar correlation values with a measure of pain as the original scale.
Depression; Geriatric; Chronic Pain; Measurement
Multi-dimensional, multi-symptom approaches to cancer symptom assessment and management have been emphasized across health disciplines. However, each dimension that is assessed significantly increases patient/subject burden. Efficient, reliable, and valid assessment of the critical dimensions of patients’ most salient symptoms is important in clinical and research settings. The Symptom Representation Questionnaire (SRQ), derived from information processing theory, assesses critical cognitive and emotional factors that are known to influence coping and outcomes. The SRQ was developed and evaluated in a three-phase process: 1) item selection, modification, and review by theoretical and clinical experts; 2) pilot evaluation of feasibility and psychometric properties; and 3) large sample psychometric evaluation. In phase three, members (n=713) of the National Ovarian Cancer Coalition participated via mailed surveys. Internal consistency was good for all subscales (α= 0.63 – 0.88). The internal structure of the SRQ was theoretically consistent except that emotional representation, identity, and consequence items all loaded onto a single factor. Between-group comparisons supported construct validity: representations differed between long-term survivors and women with active disease. Finally, there were significant correlations between SRQ subscales and Symptom Interference and Life Satisfaction. The SRQ appears to be a psychometrically sound instrument for assessing representations of cancer-related symptoms. This instrument could play an essential role in advancing knowledge of the relationships among representations of symptoms, symptom management processes, and symptom related outcomes. It could also be used in intervention research when changes in symptom representations are hypothesized to mediate changes in outcomes as a result of psycho-educational interventions.
Symptom assessment; illness representations; symptom management; ovarian cancer; cancer
Common symptoms for children with Anderson-Fabry Disease (FD) such as acroparaesthesia and gastrointestinal manifestations can only be objectively assessed in patients using a valid instrument. To date, no such instrument exists.
A preliminary 40-item measure of symptoms and experience with FD, the Fabry-specific Paediatric Health and Pain Questionnaire (FPHPQ) was developed, but lacked a formal assessment of its measurement properties. The FPHPQ was used in the Fabry Outcome Survey (FOS), a registry for all patients with a confirmed diagnosis of FD who are receiving agalsidase alfa, or are treatment naïve and who are managed by physicians participating in FOS. After an item analysis to explore how items performed and combined into domains, a battery of psychometric analyses was performed to assess the measurement properties of this new instrument.
Eighty-seven children (ages 4-18 years) completed the questionnaire. Twenty-three items in three subscales of the questionnaire emerged: pain associated with heat or exertion, pain associated with cold, and abdominal pain and fatigue symptoms. Internal consistency reliability for all three subscales was good (Cronbach alpha ≥ 0.84). Reliability was equally high for all age groups (4-7, 8-12, and 13-18). Test-retest reliability was high for all three subscales (intraclass correlation coefficient ≥ 0.74). Construct validity was demonstrated by moderate correlation with brief pain inventory (BPI), KINDL, and EQ-5D. Known group validity showed all subscales were able to discriminate between Fabry disease severity groups as classified by above or below median of the FOS MSSI (Mainz Severity Score Index) grade. The heat or exertion subscale was responsive to change in symptoms between responders and non-responders as defined by change in EQ-5D index scores between the first and second visit.
Preliminary results indicate that the measurement properties of FPHPQ are valid and reliable for assessing patient-reported symptoms of FD. The questionnaire could be a useful tool for clinicians to understand the progression of disease and monitor treatment effects. FPHPQ will be further validated and refined as the FOS registry is continuously adding more patients.
Fabry disease; Enzyme replacement therapy; Children; Paediatric Health and Pain Questionnaire; Psychometrics validation