On the generalizability of statistical expressions of health related quality of life instrument responsiveness: a data synthesis

Impact of Kaposi Sarcoma on Quality of Life Amongst HIV-infected Adults Initiating Antiretroviral Therapy in East Africa

BACKGROUND

In sub-Saharan Africa, increased antiretroviral therapy (ART) availability has improved survival after diagnosis of Kaposi sarcoma (KS) compared to the pre-ART era, but mortality among patients with KS is still considerably higher than HIV-infected persons without KS. Furthermore, among those patients with KS who are treated initially with ART without adjunct chemotherapy and who do survive, little is known about how well they function and feel - quality of life (QOL) - compared to those without KS.

METHODS

Among HIV-infected adults initiating ART in two prospective studies in Uganda, we compared those presenting with KS to those without KS. QOL was measured using the Medical Outcomes Survey-HIV instrument prior to ART initiation and at 16, 32, and 48 weeks thereafter; higher scores indicate better QOL. To ascertain the independent effect of KS versus non-KS on 11 domains of QOL and two summary scores, we created mixed effects models adjusted for directed acyclic graph-informed confounders.

RESULTS

We examined 224 participants with KS and 730 without KS, among whom 64% were women and median age was 34 years. Prior to ART initiation, participants had a median CD4+ T count of 159 cells/mm3 and plasma HIV RNA of 5.1 log10 copies/ml. In adjusted analyses prior to ART initiation, those with KS had lower mean scores in 8 of 11 QOL domains and both physical and mental health summary scores compared to those without KS. After 48 weeks of ART, those with KS had higher mean QOL scores compared those without KS in 4 domains and the mental health summary score, and lower scores in only one domain. There was no significant difference in 6 domains and the physical health summary score.

CONCLUSIONS

Amongst HIV-infected adults in East Africa, at time of ART initiation, those with KS had worse mean QOL compared to those without KS. Over the first year of ART, those with KS became comparable to or exceeded those without KS in most QOL domains. The findings indicate that some patients with KS can be treated with ART alone and further emphasize the need to predict those who will do well with ART alone versus those who need additional initial therapy.

Responsiveness and minimal clinically important difference of EQ-5D-5L in patients with coronary heart disease after percutaneous coronary intervention: A longitudinal study

Background

Although the five-level version of the EuroQol five-dimensional questionnaire (EQ-5D-5L) has been validated in various diseases, no empirical study has evaluated the responsiveness and minimal clinically important difference (MCID) of the instrument in patients with coronary heart disease (CHD), which limits the interpretability and clinical application of EQ-5D-5L. Therefore, this study aimed to determine the responsiveness and MCID of EQ-5D-5L in patients with CHD who underwent percutaneous coronary intervention (PCI) and identify the relationship between the MCID values and minimal detectable change (MDC).

Methods

Patients with CHD were recruited for this longitudinal study at the Tianjin Medical University’s General Hospital in China. At baseline and 4 weeks after PCI, participants completed the EQ-5D-5L and Seattle Angina Questionnaire (SAQ). Additionally, we used the effect size (ES) to assess the responsiveness of EQ-5D-5L. The anchor-based, distribution-based, and instrument-based methods were used in this study to calculate the MCID estimates. The MCID estimates to MDC ratios were computed at the individual and group levels at a 95% CI.

Results

Seventy-five patients with CHD completed the survey at both baseline and follow-up. The EQ-5D-5L health state utility (HSU) improved by 0.125 at follow-up compared with baseline. The ES of EQ-5D HSU was 0.850 in all patients and 1.152 in those who improved, indicating large responsiveness. The average (range) MCID value of the EQ-5D-5L HSU was 0.071 (0.052–0.098). These values can only be used to determine whether the change in scores were clinically meaningful at the group level.

Conclusion

EQ-5D-5L has large responsiveness among CHD patients after undergoing PCI surgery. Future studies should focus on calculating the responsiveness and MCID for deterioration and examining the health changes at the individual level in CHD patients.

Update on Italian-validated questionnaires for pelvic floor disorders

INTRODUCTION

Pelvic floor disorders (PFDs), which include urinary incontinence, pelvic organ prolapse, sexual dysfunction and gastrointestinal disorders, affect over 20% of the adult population. Prevalence may also be underestimated, since a certain portion of patients may be reluctant to talk to physicians about PFDs due to embarrassment. Consequently, there is a need for self-assessed diagnostic tools with the capability to screen population and collect clinical information. Symptom and quality of life (QoL) questionnaires - also identified as patient-reported outcomes (PROs) - have been developed with this purpose. Despite the large number of questionnaires available for the assessment of PFDs and QoL-related issues in the English language, few of them have been validated for the Italian language. The objective of this article is to update the list of Italian-validated PROs for PFDs along with practical information concerning literature references and suggestions on how to obtain every single questionnaire.

EVIDENCE ACQUISITION

PubMed/MEDLINE databases and websites were used to update the list of available Italian-validated questionnaires about PFDs. Once identified, the possibility to get a copy of the questionnaire was verified and steps to obtain it are reported in the tables.

EVIDENCE SYNTHESIS

Eight additional questionnaires validated into the Italian language, for diagnosis and overall management of common urinary, vaginal, sexual and bowel conditions, were retrieved. The complete list of PFDs PROS is reported in a modular format for consultation.

CONCLUSIONS

This format is intended to serve as a tool to promote appropriateness in PROs adoption while investigating PFDs in Italian patients.

The Contact Dermatitis Quality of Life Index (CDQL): Survey Development and Content Validity Assessment

BACKGROUND

There is limited measurement and reporting of quality of life (QoL) outcomes for patients with contact dermatitis (CD).

OBJECTIVE

The purpose of this study is to develop a standardized Contact Dermatitis Quality of Life index (CDQL) for adult patients.

METHODS

A list of 81 topics was compiled from a review of QoL measures used previously in CD research. A total of 2 rounds of web-based Delphi surveys were sent to physicians who registered to attend the 2018 American Contact Dermatitis Society meeting, asking that they rank the relevance of topics for measuring QoL in CD using a 4-point scale. Items met consensus for inclusion if at least 78% of respondents ranked them as relevant or very relevant, and their median score was ≥3.25.

RESULTS

Of the 210 physicians contacted, 34 physicians completed the initial survey and 17 completed the follow-up survey. A total of 22 topics met consensus for inclusion in the CDQL, addressing symptoms, emotions, functions of daily living, social and physical functions, work/school functions, and treatment.

CONCLUSIONS

This study was limited by the following factors: few open-ended questions in the initial survey, a lack of direct patient feedback, and long survey length, which likely contributed to lower survey participation. The CDQL is a comprehensive, CD-specific QoL measure developed on the basis of expert consensus via a modified Delphi process to be used by physicians and other health care professionals who care for adult patients with contact dermatitis.

Development of a Bangla version of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Bath Ankylosing Spondylitis Functional Index (BASFI)

AIM

Development of a Bangla version of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Bath Ankylosing Spondylitis Functional Index (BASFI).

METHODS

This biphasic observational study performed the translation and adaptation of the questionnaires carried out in 5 steps with pre-testing in 30 AS patients followed by the psychometric validation of the pre-final Bangla version utilizing content and construct validity in 115 AS patients. The reliability was examined through internal consistency and test-retest reliability involving 23 AS patients.

RESULTS

After pre-testing of the pre-final Bangla version of both indices, the psychometric validation found that the convergent validity of Bangla version of BASDAI showed strong correlation with C-reactive protein (r = .75) and the Maastricht Ankylosing Spondylitis Enthesitis (r = .64), and moderate correlation with erythrocyte sedimentation rate (r = .49). Again, the Bangla BASFI showed significant correlation with occiput-to-wall distance (OWD) (r = .50), mentum-to-sternum distance (MSD) (r = .50), chest expansion (CE) (r = -.40), finger-to-floor (FFD) (r = .55), number of swollen joints (r = .69), and number of enthesitis (r = .68). The divergent validity demonstrated weak correlations between BASDAI and OWD (r = .43), MSD (r = .34), CE (r = -.44), FFD (r = .47). The divergent validity of BASFI could not be assessed due to lack of a suitable comparing parameter. The instruments revealed acceptable internal consistency as Cronbach's alpha was 0.86 for BASDAI and 0.93 for BASFI. A 7-day test-retest reliability measured by the intraclass correlation coefficient were 0.80 (CI at 95% = 0.58-0.90) for BASDAI and 0.83 (CI at 95% = 95% 0.64-0.92) for BASFI respectively.

CONCLUSIONS

Bangla version of BASDAI and BASFI may be useful in disease activity and functional ability assessment in AS patients.

The SPADI and QuickDASH Are Similarly Responsive in Patients Undergoing Physical Therapy for Shoulder Pain

Study Design Prospective multicenter longitudinal cohort study. Background A key component of assessing clinical effectiveness is to compare instruments measuring similar outcomes and to select one that is sufficiently responsive. Despite their widespread use in reporting outcomes, the responsiveness of the Shoulder Pain and Disability Index (SPADI) and the shortened version of the Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH) has not been compared and reported within the same population. Objective To compare the responsiveness of the SPADI and QuickDASH in a single large cohort of patients. Methods Seven hundred sixty-seven patients referred to physical therapy with shoulder pain completed the SPADI and QuickDASH at baseline, 6 weeks, and 6 months. Patients who improved (improvers) and those who did not improve (nonimprovers) were defined using a 7-point global rating of change scale. Internal and external responsiveness was evaluated. Results For improvers, the effect size and standardized response mean were large (greater than 1.00) at 6 weeks for both the SPADI and QuickDASH and further increased for both measures at 6 months. For participants who worsened, negative effect sizes and standardized response means were larger at 6 weeks than at 6 months. The area under the curve was similar for both the SPADI (0.81) and QuickDASH (0.78), increasing to 0.85 for both at 6 months. Conclusion Both instruments are similarly able to discriminate between clinical improvers and nonimprovers at either follow-up point. J Orthop Sports Phys Ther 2017;47(8):538-547. Epub 6 Jul 2017. doi:10.2519/jospt.2017.7195.

Responsiveness of the short-form health survey and the Parkinson's disease questionnaire in patients with Parkinson's disease

Background

The responsiveness of a measurement instrument is important for understanding its ability to detect changes in the progression of a disease. We examined and compared the internal and external responsiveness of the 36-item Short-Form Health Survey (SF-36) and the 39-item Parkinson’s Disease Questionnaire (PDQ-39) in patients with Parkinson’s Disease (PD).

Methods

Seventy-four patients with PD were evaluated using the SF-36 and PDQ-39 at baseline and again after one year. In addition, their motor signs, motor difficulties of daily living, and depressive symptoms were assessed as external criteria. The internal responsiveness was examined using effect size, standardized response mean, and the Wilcoxon signed rank test. The external responsiveness was examined using receiver operating characteristic curves, correlation analyses, and regression models.

Results

Both instruments were partially sensitive to changes during the 1-year follow-up and able to discriminate between patients with improved versus deteriorated motor signs. In addition, both were similarly responsive to changes in the motor difficulties of daily living; the SF-36 appeared to be more sensitive than the PDQ-39 to changes in depressive symptoms.

Conclusions

The SF-36 and the PDQ-39 were acceptably internally and externally responsive during the 1-year follow-up.

Electronic supplementary material

The online version of this article (doi:10.1186/s12955-017-0642-8) contains supplementary material, which is available to authorized users.

Italian-Validated Questionnaires for Pelvic Floor Disorders: On Behalf of the Italian Society of Urodynamics

Introduction

Pelvic floor disorders (PFDs), which include urinary incontinence, pelvic organ prolapse, sexual dysfunction and gastrointestinal disorders, affect over 20% of adult population. The prevalence and demand for care of PFDs appear to be increasing more quickly than would be expected from simple population growth, creating substantial physical and emotional distress and a large financial burden. Suitable diagnostic tools are necessary to investigate these problems. The aim of this article is to list Symptom and Quality of Life questionnaires [briefly identified as patient-reported outcomes (PROs)] formally validated into the Italian language to provide Italian clinicians and researchers a tool for the assessment of pelvic area dysfunctions in our country. A synthetic key points summary concerning concepts behind Symptom and Quality of Life Questionnaires will be also provided.

Methods

PubMed/MEDLINE databases and websites were used to identify Italian-validated questionnaires for PFDs. Once identified, the possibility to get a copy of the questionnaire was verified and steps to obtain it are reported in the table.

Results

Questionnaires validated into the Italian language, for diagnosis and overall management of common urinary, vaginal, sexual and bowel conditions, are listed in the table.

Conclusions

This format is intended to serve as a tool to promote appropriateness in PROs adoption while investigating PFDs in Italian patients.

Effect of infertility on quality of life of women: a validation study of the Turkish FertiQoL

The fertility quality of life (FertiQoL) measure specifically evaluates the impact of fertility problems in various life areas. The aim of this study was to examine the relationship between FertiQoL and the hospital anxiety and depression scale (HADS) in the Turkish population. All female patients who underwent various fertility treatments in our infertility clinic from May 2011 to May 2014 were approached to participate in the study and 389 completed the questionnaires. Our results showed that the four core scales of the FertiQoL measure had a Cronbach's α value that was between 0.70 and 0.89. Two scales (anxiety and depression) of HADS both had a Cronbach's α value of 0.80. These values present a reliable usage of FertiQoL and HADS measures (α > 0.60). Significant negative correlations were found between the FertiQoL scales and HADS scales, ranging from -0.27 (between relational scale of FertiQoL and anxiety scale of HADS) to -0.65 (between mind-body scale of FertiQoL and depression scale of HADS). The results of this study provide supportive data to confirm that the Turkish version of FertiQol can accurately evaluate QoL in women who seek fertility treatment in Turkey.

[Possibilities and limits of patient-reported outcome exemplified by systemic lupus erythematosus and the LuLa study]

BACKGROUND

Over the last three decades patient reported outcomes (PRO) have become increasingly more important for the assessment of the course of diseases and therapy response. It represents the generic term for instruments which elicit information on various disease dimensions by direct questioning of patients and thereby collate subjective estimations and perceptions.

AIM OF THE STUDY

This article presents the current situation with respect to the utilization of PRO. The advantages and disadvantages of individual instruments are discussed exemplified by systemic lupus erythematosus (SLE) and the LuLa study.

CONCLUSION

The PRO instrument collates subjective estimations of various aspects of diseases directly from the patients. The PRO is mainly used to survey (health-related) quality of life but can also be used to reflect other disease-associated aspects. Various institutions promote the use of PRO in clinical trials for assessment of approval for pharmaceutical and medical products because ultimately only benefits for the patients are of relevance. The development of PRO instruments requires the same extensive psychometric testing as physicians instruments to measure clinical endpoints. Because of the heterogeneous sociodemographic composition of patient collectives, particular attention has to be given to cultural and linguistic adaptation. In addition to common challenges, such as missing values, under-reporting, over-reporting and response shift, subjective opinions can be influenced by other contextual factors, such as life situations unrelated to the disease. Alteration of internal standards or conceptualization can lead to interpretation difficulties in the long-term. Determinants of discordant estimations between physicians and patients need to be considered when using PRO but none of the aspects is generally better than the other.

Validity of LupusQoL-China for the assessment of health related quality of life in Chinese patients with systemic lupus erythematosus

Objectives

To adapt and assess the validity and reliability of LupusQoL for use in Chinese patients with systemic lupus erythematosus (SLE).

Methods

Debriefing interviews of subjects with SLE guided the language modifications of the tool. The process of adaptation proceeded according to the guideline and pre-testing results of LupusQoL-China. 220 SLE patients completed LupusQoL-China and a generic preference-based measurement of health EuroQoL scale (EQ-5D), and 20 patients repeated them after 2 weeks. Internal consistency (ICR) and test-retest (TRT) reliability, convergent and discriminant validity were examined. Factor analysis and Rasch analysis were performed.

Results

The mean (SD) age of the 208 subjects with SLE was 33.93 (±9.19) years. ICR and TRT of the eight domains ranged from 0.811 to 0.965 and 0.836 to 0.974, respectively. The LupusQoL-China domains demonstrated substantial evidence of construct validity when compared with equivalent domains on the EQ-5D (physical health and usual activities r = −0.63, pain and pain/discomfort r = −0.778, emotional health and anxiety/depression r = −0.761, planning and usual activities r = −0.560). Most LupusQoL-China domains could discriminate patients with varied disease activities and end-organ damage (according to SELENA-SLEDAI and SLICC-DI). The principal component analysis revealed six factors, and confirmatory factor analysis result of which is similar to eight factors model.

Conclusions

These results provide evidence that the LupusQoL-China is valid as a disease-specific HRQoL assessment tool for Chinese patients with SLE.

The reliability, validity and responsiveness of the Thai version of systemic lupus erythematosus quality of life (SLEQOL-TH) instrument

Objectives

The English version of the Systemic Lupus Erythematosus Quality of Life Questionnaire (SLEQOL) is a validated disease-specific quality of life instrument. The aim of this study was to evaluate the psychometric properties of the Thai version of the SLEQOL (SLEQOL-TH).

Methods

Two independent translators translated the SLEQOL into Thai. The back translation of this version was performed by two other independent translators. The final version, SLEQOL-TH, was completed after resolving the discrepancies revealed by the back translation. One hundred and nine patients with SLE were enrolled to test the reliability, construct validity, floor and ceiling effects, and sensitivity to the changes of the SLEQOL-TH at six months. The differential item functioning (DIF) between the Thai and English versions was analyzed using the partial gamma.

Results

The internal consistency of the SLEQOL-TH was satisfactory with the overall Cronbach’s alpha of 0.86. The test-retest reliability of the SLEQOL-TH was acceptable with the intra-class correlation coefficient of 0.86. Low correlations between the SLEQOL-TH and SLEDAI were observed. The total score of the SLEQOL-TH was moderately responsive to changes in quality of life, with a standardized response mean of 0.50. When comparing the SLEQOL-TH from Thai SLE patients with the original SLEQOL version obtained from Singapore SLE patients, 11 out of 40 items showed a moderate to large DIF.

Conclusions

The SLEQOL-TH has acceptable psychometric properties and shows construct validity. In comparison with the English version of SLEQOL, there are some items that showed DIF. The applicability of the SLEQOL-TH in real-life clinical practice and clinical trials needs to be determined.

Can manual ability be measured with a generic ABILHAND scale? A cross-sectional study conducted on six diagnostic groups

OBJECTIVES

Several ABILHAND Rasch-built manual ability scales were previously developed for chronic stroke (CS), cerebral palsy (CP), rheumatoid arthritis (RA), systemic sclerosis (SSc) and neuromuscular disorders (NMD). The present study aimed to explore the applicability of a generic manual ability scale unbiased by diagnosis and to study the nature of manual ability across diagnoses.

DESIGN

Cross-sectional study.

SETTING

Outpatient clinic homes (CS, CP, RA), specialised centres (CP), reference centres (CP, NMD) and university hospitals (SSc).

PARTICIPANTS

762 patients from six diagnostic groups: 103 CS adults, 113 CP children, 112 RA adults, 156 SSc adults, 124 NMD children and 124 NMD adults.

PRIMARY AND SECONDARY OUTCOME MEASURES

Manual ability as measured by the ABILHAND disease-specific questionnaires, diagnosis and nature (ie, uni-manual or bi-manual involvement and proximal or distal joints involvement) of the ABILHAND manual activities.

RESULTS

The difficulties of most manual activities were diagnosis dependent. A principal component analysis highlighted that 57% of the variance in the item difficulty between diagnoses was explained by the symmetric or asymmetric nature of the disorders. A generic scale was constructed, from a metric point of view, with 11 items sharing a common difficulty among diagnoses and 41 items displaying a category-specific location (asymmetric: CS, CP; and symmetric: RA, SSc, NMD). This generic scale showed that CP and NMD children had significantly less manual ability than RA patients, who had significantly less manual ability than CS, SSc and NMD adults. However, the generic scale was less discriminative and responsive to small deficits than disease-specific instruments.

CONCLUSIONS

Our finding that most of the manual item difficulties were disease-dependent emphasises the danger of using generic scales without prior investigation of item invariance across diagnostic groups. Nevertheless, a generic manual ability scale could be developed by adjusting and accounting for activities perceived differently in various disorders.

Relationship between quality of life and distress in infertility: a validation study of the Dutch FertiQoL

BACKGROUND

This study examined the relationship between emotional distress as measured by the Hospital Anxiety and Depression Scale (HADS) and the Fertility Quality of Life (FertiQoL) questionnaire.

METHODS

The FertiQoL and HADS were distributed to a random sample of 785 patients attending 29 Dutch clinics for medically assisted reproduction. FertiQoL was psychometrically tested for reliability. Pearson's correlations were calculated between subscales of FertiQoL and HADS. Using an independent t-test, differences between patient subgroups were computed for both instruments. The threshold for clinically meaningful depression/anxiety on the HADS subscales was used to ascertain the critical threshold for high distress on the FertiQoL scales.

RESULTS

FertiQoL and HADS were completed by 583 patients (response 74%). Reliability of FertiQoL scales was high (reliability coefficient between 0.72 and 0.91). Significant negative correlations were found between FertiQoL subscales and HADS scores for anxiety and depression, ranging from -0.29 to -0.71. Means on FertiQoL scales and HADS scales of couples undergoing an assisted reproductive technology (ART) treatment and a non-ART treatment did not differ significantly. Patients scoring above the HADS threshold for pathology on anxiety had an average FertiQoL score of 58.8, whereas patients exceeding the HADS depression threshold had a FertiQoL total score of 51.9 (range 0-100).

CONCLUSIONS

Our study confirms the expected negative relation between quality of life as measured by FertiQoL and anxiety and depression. The data support that FertiQoL reliably measures QoL in women facing infertility. FertiQoL enables clinicians to tailor care more specifically to the patient in a comprehensive way.

Comparison of responsiveness of validated outcome measures after surgery for stress urinary incontinence

PURPOSE

We compared the responsiveness of several validated incontinence, pelvic floor and quality of life outcome measures in women undergoing surgery for stress urinary incontinence to assist investigators in selecting appropriate outcomes in future trials of stress urinary incontinence therapy.

MATERIALS AND METHODS

This is an ancillary analysis of data from a multicenter, randomized trial comparing tension-free vaginal tape and transobturator slings. All patients were asked to complete outcome measures at baseline and again 1 year postoperatively, including Incontinence Severity Index, Pelvic Floor Distress Inventory-Short Form 20, Pelvic Floor Impact Questionnaire-Short Form 7, Pelvic Organ Prolapse/Urinary Incontinence Sexual Function Questionnaire 12, SF-12® and a 3-day bladder diary. They also completed the Patient Global Index of Improvement at 1 year. We assessed the responsiveness of each outcome measure by calculating a standardized response mean and performing receiver operator characteristics curve analysis.

RESULTS

Incontinence Severity Index, Pelvic Floor Distress Inventory-Short Form 20, Urinary Distress Inventory-Short Form, Pelvic Floor Impact Questionnaire-Short Form 7 and Urinary Impact Questionnaire-Short Form 7 showed excellent responsiveness (standardized response mean ≥1.0). Using receiver operator characteristics curve data the bladder diary had the greatest ability to discriminate patients who did vs did not improve (area under the curve 0.97). Incontinence Severity Index, Pelvic Floor Distress Inventory-Short Form 20 and Urinary Distress Inventory-Short Form also showed strong responsiveness according to these data (area under the curve greater than 0.7).

CONCLUSIONS

In this study of women undergoing mid urethral sling surgery for stress urinary incontinence the greatest responsiveness was noted on Incontinence Severity Index, Pelvic Floor Distress Inventory-Short Form 20, Urinary Distress Inventory-Short Form and bladder diary. Thus, they may be preferable as primary outcome measures in trials of stress urinary incontinence treatment.

Responsiveness of the EQ-5D to HADS-identified anxiety and depression

RATIONALE

The use of generic measures of health-related quality of life enables cost effectiveness comparisons of different health care interventions to be made. Nevertheless, there exists a concern that generic instruments may be insufficiently sensitive to detect the differences or changes in outcome identified by condition-specific instruments. This paper compares the psychometric properties of the EQ-5D generic instrument with a widely used specific measure of distress, the Hospital Anxiety and Depression Scale (HADS).

METHOD

The analysis was based on data obtained from a large sample of women (n = 3119) with low-grade cervical cytological abnormalities detected at routine screening. These women completed EQ-5D and HADS questionnaires at recruitment and at 12 months thereafter. We examined the strength of association between HADS-determined severity of distress and EQ-5D scores at recruitment and between changes in severity and in scores over time.

RESULTS

A higher likelihood of HADS-identified anxiety and/or depression was associated with significantly lower EQ-5D index and visual analogue scores. Over time, the EQ-5D score rose significantly when the likelihood of an individual representing a HADS-defined anxiety and/or depression case decreased.

CONCLUSION

We conclude that the EQ-5D has shown itself to be responsive to differing degrees of HADS-assessed distress, although generalization beyond the UK context requires further investigation.

Pictorial Representation of Illness and Self Measure Revised II (PRISM-RII): a novel method to assess perceived burden of illness in diabetes patients

Background

The Pictorial Representation of Illness and Self Measure (PRISM) has been introduced as a visual measure of suffering. We explored the validity of a revised version, the PRISM-RII, in diabetes patients as part of the annual review.

Methods

Participants were 308 adult outpatients with either type 1 or type 2 diabetes. Measures: (1) the PRISM-RII, yielding Self-Illness Separation (SIS) and Illness Perception Measure (IPM); (2) the Problem Areas in Diabetes (PAID) scale, a measure of diabetes-related distress; (3) the WHO-5 Well-Being Index; (4) and a validation question on suffering (SQ). In addition, patients' complication status, comorbidity and glycemic control values(HbA1c) were recorded.

Results

Patients with complications did have marginally significant higher scores on IPM, compared to patients without complications. Type 2 patients had higher IPM scores than Type 1 patients. SIS and IPM showed low intercorrelation (r = -.25; p < .01). Convergent validity of PRISM-RII was demonstrated by significant correlations between IPM and PAID (r = 0.50; p < 0.01), WHO-5 (r = -.26; p < 0.01) and SQ (r = 0.36; p < 0.01). SIS showed only significant correlations with PAID (r = -0.28; p < 0.01) and SQ (r = -0.22; p < 0.01). Neither IPM nor SIS was significantly associated with HbA1c. The PRISM-RII appeared easy to use and facilitated discussion with care providers on coping with the burden of diabetes.

Conclusion

PRISM-RII appears a promising additional tool to assess the psychological burden of diabetes.

An evaluation of the responsiveness of a comprehensive set of outcome measures for children and adolescents with traumatic brain injuries

The relative responsiveness of nine outcome measure scales was evaluated with 33 children and adolescents (aged 4-18 years) who had sustained traumatic brain injuries. Scales were selected to evaluate outcomes from each of the World Health Organization (WHO) International Classification of Functioning, Disability and Health domains. The outcome measures were administered to all participants during their inpatient rehabilitation stay and again at a follow-up clinic visit. No single outcome measure captured the diversity of improvement in this sample. The measures agreed that improvement had occurred, but did not agree about which children were improving. This result suggests that the scales were measuring different skills and outcomes. Three of the measures used in combination, either the Child Health Questionnaire or the Functional Independence Measure for Children, the American Speech-Language-Hearing Association National Outcome Measures System (Birth to Kindergarten NOMS/School-aged Health Care) and the Gross Motor Function Measure, are sufficient to detect change in each of the children where change occurred. The Pediatric Evaluation of Disability Inventory and the MultiAttribute Health Status Classification were the least responsive of the nine measures used.

Expressing treatment-associated changes

The Osteoarthritis Research Society International is attempting to establish a consensus on outcome measures, so as to facilitate comparability between different clinical studies in this area of research. There are no general recommendations on how changes in outcome measure (effect size) should be expressed. We therefore used data from a recently published study to express change as: a) the mean of the change from baseline divided by the individual baseline, b) the median of the change from baseline divided by the individual baseline, c) the mean of the change from baseline divided by the SD of baseline and d) the median of change from baseline divided by the SD of baseline. The results show that the correlations between different ways of expressing effect sizes were poor and the perceived relative magnitudes of various effects depended on how they were expressed. Organisations aiming at consensus ought to recommend the way in which change ought to be expressed. Until they do, authors should justify their choice of expression, particularly if it critically influences their conclusion, and/or present their data as fully as possible on a website.

Development and preliminary validation of a systemic lupus erythematosus-specific quality-of-life instrument (SLEQOL)

OBJECTIVES

Systemic lupus erythematosus (SLE), a chronic illness with an unpredictable and variable course, profoundly affects the quality of life (QOL). General health questionnaires are used to assess QOL in SLE, but a disease-specific instrument could offer enhanced responsiveness and content validity. We detail the steps we took to develop and validate a new SLE-specific QOL instrument, SLEQOL.

METHODS

Rheumatology professionals nominated items that they felt were important determinants of QOL of SLE patients. One hundred SLE patients were asked to assess the importance and frequency of occurrence of these items and to suggest those that had not been listed. Item reduction was performed using Rasch model and factor analyses to create a new questionnaire in English. This final questionnaire was administered to a cohort of 275 patients to study its psychometric properties.

RESULTS

Fifty-one items covering a wide range of QOL concerns were identified. The patients' responses led to the elimination of 11. The new questionnaire of 40 items was found to have Cronbach's alpha of 0.95 and to consist of eight domains covering physical, mental and social QOL issues. It has good test-retest reliability, poor to fair cross-sectional correlation with the SF-36, with poor correlation with lupus activity or damage indices. The SLEQOL was more responsive to change than the SF-36.

CONCLUSIONS

We have developed a new 40-item SLEQOL in English and showed that it is valid for use in SLE patients in Singapore. It offers better content validity and responsiveness to change than the SF-36.

Why generic and disease-specific quality-of-life instruments should be used together for the evaluation of patients with persistent allergic rhinitis

BACKGROUND

The importance of assessing health-related quality of life (HRQL) of patients with allergic rhinitis (AR) has been well established, but the specific roles of rhinitis-specific or general health instruments have not been delineated.

OBJECTIVE

We analysed the psychometric properties of a disease-specific instrument, the Rhinoconjunctivitis Quality-of-Life Questionnaire (RQLQ) and the general health instrument, the Medical Outcome Short-Form 36 (SF-36) as they are employed in combination in patients with persistent AR in clinical practice.

METHOD

We analysed the data collected from a prospective study of 43 newly diagnosed patients with persistent AR and 44 controls. We interviewed the patients four times, at baseline, weeks 4, 8 and 10.

RESULTS

The RQLQ and SF-36 have good discriminative property, internal consistency, and test-retest reliability. The RQLQ is superior to the SF-36 as an evaluative instrument because more of its domains respond to change, the magnitude of change was greater, and the response was faster. The SF-36 is more susceptible to floor and ceiling effects. Both instruments are unsuitable for mildly symptomatic patients based on Rasch model analysis. Each questionnaire assesses a distinct and significant portion of the total HRQL of persistent AR.

CONCLUSION

The SF-36 and RQLQ are good for discriminating rhinitis patients from controls, but the former is poor for detecting changes in QOL. Both are inappropriate for mildly symptomatic patients. Each instrument measures non-overlapping halves of the measurable HRQL. For an assessment of the HRQL in persistent AR that is complete and responsive both instruments should be employed together.

Disease adaptation may have decreased quality-of-life responsiveness in patients with chronic progressive neurological disorders

OBJECTIVE

We hypothesized that disease adaptation could be measured in chronic progressive neurological disorders (CPND) through paired longitudinal comparisons of quality of life (QOL) and health status (HS) and of the mental health (MH) and physical health (PH) domains of QOL instruments.

STUDY DESIGN AND SETTING

We identified 193 quantitative studies of QOL and HS in a systematic review of episodic (END) and chronic progressive (CPND) neurological disorders. Effect size or other responsiveness measures were analyzed in 31 studies that included paired longitudinal comparisons of QOL-HS, MH-PH, or both. Responsiveness means were compared using the paired-sample t-test or sign test.

RESULTS

In 12 paired comparisons, QOL responsiveness was significantly lower than HS (P=.05, sign test). In 53 paired MH-PH effect-size comparisons, MH responsiveness was lower than PH (P=.02, t=2.48, paired sample). Significantly lower MH responsiveness was observed in 28 paired CPND comparisons (P < .01, t=3.86, paired sample) but not in 25 paired END comparisons (P=.50, t=0.68, paired sample).

CONCLUSION

Lower responsiveness of QOL in CPND may be related to disease adaptation. Further prospective studies are needed to confirm our findings and to investigate the importance of disease adaptation in the evaluation of neurological disease and in health resource allocation.

Health-related quality of life during treatment of elderly patients with hypertension: results from the Study on COgnition and Prognosis in the Elderly (SCOPE)

The Study on COgnition and Prognosis in the Elderly (SCOPE) was a multinational, randomised, double-blind study to assess the effects of candesartan 8-16 mg daily on cardiovascular events and cognitive function in elderly patients (aged 70-89 years) with mild to moderate hypertension. A total of 4937 patients were randomised to candesartan or placebo with other antihypertensive drugs (mostly diuretics, beta-blockers, and calcium antagonists) added as needed to control blood pressure. Only 16% of the patients in the control group received placebo alone. The mean follow-up was 3.7 years. The aim of this health-related quality of life (HRQL) substudy analysis was to investigate changes in HRQL during antihypertensive treatment, and possible differences in patients receiving candesartan-based or other antihypertensive treatment. Three validated HRQL instruments were used: the Psychological General Well-being (PGWB) Index, the Subjective Symptoms Assessment Profile (SSA-P), and the EuroQoL Health Utility Index (EuroQoL). The HRQL was generally good at baseline and well preserved during follow-up in the presence of substantial blood pressure reductions in both treatment groups. Several of the observed changes in score from baseline to last visit favoured candesartan-based compared to control treatment, particularly the changes in PGWB Anxiety (-0.5 vs -1.0, P=0.01), PGWB Positive well-being (-0.8 vs -1.1, P=0.04), SSA-P Cardiac symptoms (0.03 vs 0.10, P=0.03), and EuroQoL Current health (-3.1 vs -5.3, P=0.008). This favourable result may be related to the somewhat lower blood pressure associated with candesartan-based treatment. In conclusion, there should be no reason to withhold modern antihypertensive therapy in elderly patients due to concerns for a negative effect on HRQL.

On assessing responsiveness of health-related quality of life instruments: guidelines for instrument evaluation

A lack of clarity exists about the definition and adequate approach for evaluating responsiveness. An overview is presented of different categories of definitions and methods used for calculating responsiveness identified through a literature search. Twenty-five definitions and 31 measures were found. When applied to a general and a disease-specific quality of life questionnaire large variation in results was observed, partly explained by different goals of existing methods. Four major issues are considered to claim the usefulness of an evaluative health-related quality of life (HRQL) instrument. Their relation with responsiveness is discussed. The confusion about responsiveness arises mostly from a lack of distinction between cross-sectional and longitudinal validity and from a lack of distinction between responsiveness defined as the effect of treatment and responsiveness defined as the correlation of changes in the instrument with changes in other measures. All measures of what is currently called responsiveness can be looked at as measures of longitudinal validity or as measures of treatment effect. The latter ones tell us little about how well the instrument serves its purpose and are only of use in interpreting score changes. We therefore argue that the concept of responsiveness can be rejected as a separate measurement property of an evaluative instrument.

Responsiveness of the quality of life in epilepsy inventory (QOLIE-89) in an antiepileptic drug trial

This study examined relationships among responsiveness indices for health-related quality of life (HRQOL) measures administered to adults with epilepsy enrolled in an antiepileptic drug trial. The Quality of Life in Epilepsy (QOLIE)-89 was completed at baseline and at a 28-week follow-up. Six responsiveness indices (effect size (ES), standardized response mean (SRM), responsiveness statistic, paired t-test, area under receiver operating characteristic curve or ROC, F-statistic) were calculated for each of the 16 QOLIE-89 scales, using two different external criteria for clinically significant change: (1) attainment of freedom from seizures with altered awareness, and (2) a two-category improvement between baseline and follow-up in a self-rating of the subject's overall condition. Spearman correlations among the six responsiveness indices for the 16 QOLIE-89 scales tended to be moderate to large (Spearman's p = 0.53-1.00; p's < 0.05 for 29 out of the 30 correlations). Rankings of the 16 scales across the two external criteria for change were similar for the responsiveness statistic (Spearman's p = 0.62; p < 0.05), but dissimilar for the other responsiveness indices (all p > 0.05). Both ES and SRM were well predicted by the other indices, except for ROC, using regression modeling. In conclusion, results using different responsiveness indices are comparable for a given external criterion. However, only the responsiveness statistic yielded robust results across two different external criteria. Responsiveness of this HRQOL measure can be reported in terms of previously established benchmarks for ESs, which can be predicted from other indices.

Comparative responsiveness of generic and specific quality-of-life instruments

We assessed the relative responsiveness of generic and specific quality of life instruments in 43 randomized controlled trials that compared head-to-head 31 generic and 84 specific instruments. Using weighted effect size as the metric of responsiveness, we assessed the impact of instrument type, disease category, and magnitude of underlying therapeutic effect on responsiveness, and assessed the responsiveness of specific instruments relative to the corresponding domains of generic measures. In studies with a nonzero therapeutic effect, specific instruments (mean = 0.57) were significantly more responsive than generic instruments (mean = 0.39, P =.01), and than the corresponding domains of generic instruments (mean = 0.40, P =.03). Studies with low, medium, and high therapeutic effects showed a corresponding gradation in responsiveness differences between specific and generic instruments. We conclude that, overall, specific instruments are more responsive than generic tools, and that investigators may come to misleading conclusions about relative instrument responsiveness if they include studies in which the magnitude of the underlying therapeutic effect is zero.

Statistical significant change versus relevant or important change in (quasi) experimental design: some conceptual and methodological problems in estimating magnitude of intervention-related change in health services research

This paper aims to identify problems in estimating and the interpretation of the magnitude of intervention-related change over time or responsiveness assessed with health outcome measures. Responsiveness is a problematic construct and there is no consensus on how to quantify the appropriate index to estimate change over time between baseline and post-test designs. This paper gives an overview of several responsiveness indices. Thresholds for effect size (or responsiveness index) interpretation were introduced some thirty years ago by Cohen who standardised the difference-scores (d) with the pooled standard deviation (d/SD(pooled)). However, many effect sizes (ES) have been introduced since Cohen's original work and in the formula of one of these ES, the mean change scores are standardised with the SD of those change scores (d/SD(change)). When health outcome questionnaires are used, this effect size is applied on a wide scale and is represented as the Standardized Response Mean (SRM). However, its interpretation is problematic when it is used as an estimate of magnitude of change over time and interpreted with the thresholds, set by Cohen for effect size (ES) which is based on SD(pooled). Thus, in the case of using the SRM, application of these well-known cut-off points for pooled standard deviation units namely: 'trivial' (ES < 0.20), 'small' (ES > or = 0.20 < 0.50), 'moderate' (ES > or = 0.50 < 0.80), or large (ES > or = 0.80), may lead to over- or underestimation of the magnitude of intervention-related change over time due to the correlation between baseline and outcome assessments. Consequently, taking Cohen's thresholds for granted for every version of effect size indices as estimates of intervention-related magnitude of change, may lead to over- or underestimation of this magnitude of intervention-related change over time.

Onychomycosis: health-related quality of life considerations

The symptoms of onychomycosis and their impact on personal appearance are important determinants of patients' perceptions of their own health. The effect of onychomycosis is greater on psychosocial than physical functioning and is directly related to the extent of nail involvement. This review identified a number of disease-targeted questionnaires that have been developed to assess the impact of onychomycosis and its treatment on health-related quality of life (HR-QOL). The instruments differ considerably in the extent to which they have been psychometrically tested. Most have been shown to provide both valid and reliable measurement of HR-QOL in patients with onychomycosis of the toes. However, not all have been tested in patients with fingernail disease. The generic and disease-targeted scales of most of the available questionnaires exhibit poor variability, which may limit their responsiveness to clinically important change. Only one instrument, the Onychomycosis Disease-Specific Questionnaire, has been incorporated into a clinical trial. Thus, information relating to the impact of onychomycosis treatment on HR-QOL is limited. Future efforts should focus on the systematic evaluation of existing questionnaires in all populations for which they were developed. In addition, it is important that disease-targeted measures be included in future clinical trials so that a better understanding of the impact of onychomycosis treatment on patient HR-QOL may be gained.

How to validate clinically important change in health-related functional status. Is the magnitude of the effect size consistently related to magnitude of change as indicated by a global question rating?

Some clinical trials perform repeated measurement over time and estimate clinically relevant change in an instrument's score with global ratings of perceived change or so-called transition questions. The conceptual and methodological difficulties in estimating the magnitude of clinically relevant change over time in health-related functional status (HRFS) are discussed. This paper investigates the concordance between the amount of serially assessed change with effect size estimates (the researcher's perspective) and global ratings of perceived change (the patient's perspective). A total of 217 patients who were scheduled for diagnostic examination were included, and the Minnesota Living with Heart Failure Questionnaire, extended with MOS-20 items, was assessed before and after medical intervention (percutaneous transluminal coronary angioplasty, coronary artery bypass grafting or pharmaco-therapy). Global questions were applied to assess perceived change over time for every item from domains of physical and emotional functioning and used as the external criterion of relevant change in the analysis of items. Global questions corresponding with overall change in these domains were used in the comparison of change in physical and emotional functioning scales. Two effect size indices were used: (i) ES (mean change/SDpooled) and (ii) ES (mean change/SDchange). A method is described to calculate a value indicating the extent of discordance between the researcher's interpretation of magnitude of change and the external criterion (the patient's perspective). Findings suggest that effect size (ES) (mean change/SDpooled) was in keeping with the magnitude of change indicated by patients' judgements, or their category of subjective meaning, for all scales. Furthermore, in cases in which the magnitude of change estimated with the SRM (mean change/SDchange) was not confirmed empirically by the external criterion ratings, the discordance could be interpreted as a trivial discordance.

Developing a disease-specific quality of life measure for people with multiple sclerosis

OBJECTIVES

To develop a patient-completed disease-specific measure of quality of life in multiple sclerosis and to validate the measure in a community-based population of people with multiple sclerosis.

METHODS

The items in the scale were selected in focus group sessions of people with multiple sclerosis. The initial scale included 25 items and was tested in subgroups of 150 people from a population register of people with multiple sclerosis in Leeds. Following further developmental phases, a restructured 16-item scale was tested on a random sample of 200 people with multiple sclerosis from the population register, stratified according to disease course. This led to a final eight-item unidimensional scale, the Leeds Multiple Sclerosis Quality of Life (LMSQoL) scale.

RESULTS

After initial development a 16-item scale was found to be both reliable and valid. Cronbach's alpha for the 16-item scale was 0.86. The test-retest correlation was 0.74, using a two-week retest interval. However, convergent validity with the General Well Being Index was 0.67 and with the SF-36 Physical Function Scale was 0.68. This suggested that the scale straddled these two concepts and was confirmed by fit of the data to the Rasch measurement model. This revealed the potential for a reduced eight-item version of the scale. The eight-item scale had a closer association to well-being (0.83) than to physical function (0.39), had good internal consistency (0.79) and test-retest reliability (0.85). There were virtually no floor or ceiling effects for the scale.

CONCLUSIONS

The study presents a disease-specific measure of quality of life in multiple sclerosis, the Leeds Multiple Sclerosis Quality of Life (LMSQoL) scale. The instrument is brief, easy to use and practical to administer in clinic or as a postal questionnaire. It measures a construct related to well-being, and provides an important adjunct to the measurement of outcome in multiple sclerosis.

The rating scale preference measure as an evaluative measure in systemic lupus erythematosus

Preference measures may be useful tools to assess patients' overall health-related quality of life. We studied the validity and sensitivity to change of the rating scale preference measure in patients with systemic lupus erythematosus (SLE), and compared its properties with those of the patient global assessment of SLE activity, in a prospective longitudinal observational study of changes in the symptoms and clinical disease activity of 23 patients. Patients were assessed every two weeks for up to 40 weeks. Construct validity was assessed by the strength of correlations between changes over time in the rating scale preference measure and patient global assessment and changes in the physician global assessment, Systemic Lupus Activity Measure (SLAM), European Consensus Lupus Activity Measure (ECLAM), the British Isles Lupus Assessment Group index (BILAG), and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Changes in the rating scale were more highly correlated with changes in each of these standards than were changes in the patient global assessment, demonstrating the construct validity of this measure. Sensitivity to change was measured using the two-week interval of greatest change in either the physician global assessment or the SLE activity measures as standards. The rating scale preference measure was less sensitive to change than the patient global assessment when tested against four different standards. The sensitivity to change of the rating scale was less than one-half that of the patient global assessment when either the SLAM or ECLAM was used as the standard. Although these results support the validity of the rating scale as a measure of health-related quality of life in patients with SLE, its limited sensitivity to change may make it less attractive as an endpoint measure in clinical trials.

Responsiveness of observational and self-report methods for assessing disability in mobility in patients with osteoarthritis

OBJECTIVE

To establish the responsiveness of observational and self-report methods for the assessment of disability in mobility in patients with osteoarthritis (OA).

METHODS

Data from 186 patients with hip OA or knee OA were used. Data from 1 observational method and 4 self-report methods for the assessment of disability in mobility were collected at week 0 and again 12 weeks later. Using correlations and factor analysis, the relationships among changes in these 5 methods were established.

RESULTS

Intercorrelations between change scores of the self-report methods ranged from 0.12 to 0.34. Correlations between the observational method and the self-report methods ranged from 0.14 to 0.26. In the factor analysis, both the self-report methods and the observational method loaded on the same factor.

CONCLUSION

In a longitudinal design, no evidence for differential responsiveness of observational and self-report methods was obtained. Because of the advantages of questionnaires (they are easier to use, less time-consuming, and less of a burden to subjects), this implies that the use of self-report methods is to be preferred over observational methods.

Relationship between depression, anxiety and quality of life: a study of stroke patients compared to chronic low back pain and myocardial ischemia patients

The prevalence of anxiety disorders and depression is assessed as between 20 and 50% following stroke. Depressive persons tend to give their overall life situation a worse rating than their relatives or physicians because of negative cognitions. Nevertheless, research concerning Quality of Life (QoL) after stroke hardly ever takes into account the methodological bias of assessing QoL only by self-rating. The aim of this study was to point out the important relationship between depression, anxiety and the autoassessment of QoL. QoL was markedly affected in the poststroke patients and in the chronic low back pain and myocardial ischemia patients, and it was rated worst by the most seriously depressed subjects. Clinical studies focusing on the ever more significant evaluation criterion 'health-related QoL' after stroke should take into account the high prevalence of anxiety and depressive symptoms and their major influence on the patients' self-evaluated QoL.