Evaluation of the methodological quality of systematic reviews of health status measurement instruments

A systematic review of measurement properties of health-status instruments is a tool for evaluating the quality of instruments. Our aim was to appraise the quality of the review process, to describe how authors assess the methodological quality of primary studies of measurement properties, and to describe how authors evaluate results of the studies. Literature searches were performed in three databases. One hundred and forty-eight reviews were included. The purpose of included reviews was to identify health status instruments used in an evaluative application and to report on the measurement properties of these instruments. Two independent reviewers selected the articles and extracted the data. Reviews were often of low quality: 22% of the reviews used one database, the search strategy was often poorly described, and in many cases it was not reported whether article selection (75%) and data extraction (71%) was done by two independent reviewers. In 11 reviews the methodological quality of the primary studies was evaluated for all measurement properties, and of these 11 reviews only 7 evaluated the results. Methods to evaluate the quality of the primary studies and the results differed widely. The poor quality of reviews hampers evidence-based selection of instruments. Guidelines for conducting and reporting systematic reviews of measurement properties should be developed.     

The COSMIN checklist for evaluating the methodological quality of studies on measurement properties: A clarification of its content

Background  

The COSMIN checklist (COnsensus-based Standards for the selection of health status Measurement INstruments) was developed in an international Delphi study to evaluate the methodological quality of studies on measurement properties of health-related patient reported outcomes (HR-PROs). In this paper, we explain our choices for the design requirements and preferred statistical methods for which no evidence is available in the literature or on which the Delphi panel members had substantial discussion.     

Analyse der Dynamik des Ziliarmuskels während der Akkommodation

Background. The magnitude of anterioaxial shift of the human ciliary muscle during accommodation and its ceasing of ciliary function with advanced age are still unknown. Patients and methods. A total 105 patients (aged 10–91 years) were examined by high-resolution ultrasound biomicroscopy during disaccommodation and voluntary accommodation. Accommodative changes in the total area of the ciliary muscle and in the outer contour were quantified with a specially developed software program for automatic contour determination. Results. A significant anterior shift independent of age was observed in the total area of the ciliary muscle and defined points on the outer contour of the muscle in the range of 56–121 μm, while the inward displacement was less obvious. A decrease in the magnitude of configurational changes during accommodation was observed with age. Conclusion. The new software program could be useful in further investigations of the accommodative process and evaluation of the potential causes of presbyopia.     

Validation of the gastrointestinal quality of life index for patients with potentially operable periampullary carcinoma

BACKGROUND: A disease-specific quality of life questionnaire is not available for patients with periampullary carcinoma, although cancer-specific questionnaires and the Gastrointestinal Quality of Life Index (GIQLI) have been used. The aim of this study was to validate the GIQLI for patients with periampullary tumours and to evaluate if subscales of the GIQLI could be identified to allow a more detailed assessment of the patients' quality of life. METHODS: Patients with periampullary carcinoma, included in a study concerning diagnostic laparoscopy, were asked about symptoms and completed a questionnaire comprising the Medical Outcomes Study (MOS) 24 questionnaire, the GIQLI and one question of the Rotterdam Symptom Check List (RSCL). Clinical interpretation and statistical factor analysis were used to identify subscales of the GIQLI. RESULTS: The GIQLI could be divided into four subscales, measuring physical well-being, mental well-being, digestion and defaecation. All four subscales had a good internal reliability and the construct validity was supported by the pattern of correlations with the MOS and RSCL as well as differences in subscale scores for patients with or without certain symptoms. CONCLUSION: In patients with periampullary tumours the GIQLI can be divided into four subscales, measuring different aspects of quality of life. These subscales provide insight into the different problems affecting the patient.     

Effectiveness of exercise therapy: a best-evidence summary of systematic reviews

The purpose of this project was to summarise the available evidence on the effectiveness of exercise therapy for patients with disorders of the musculoskeletal, nervous, respiratory, and cardiovascular systems. Systematic reviews were identified by means of a comprehensive search strategy in 11 bibliographic databases (08/2002), in combination with reference tracking. Reviews that included (i) at least one randomised controlled trial investigating the effectiveness of exercise therapy, (ii) clinically relevant outcome measures, and (iii) full text written in English, German or Dutch, were selected by two reviewers. Thirteen independent and blinded reviewers participated in the selection, quality assessment and data-extraction of the systematic reviews. Conclusions about the effectiveness of exercise therapy were based on the results presented in reasonable or good quality systematic reviews (quality score > or = 60 out of 100 points). A total of 104 systematic reviews were selected, 45 of which were of reasonable or good quality. Exercise therapy is effective for patients with knee osteoarthritis, sub-acute (6 to 12 weeks) and chronic (> or = 12 weeks) low back pain, cystic fibrosis, chronic obstructive pulmonary disease, and intermittent claudication. Furthermore, there are indications that exercise therapy is effective for patients with ankylosing spondylitis, hip osteoarthritis, Parkinson's disease, and for patients who have suffered a stroke. There is insufficient evidence to support or refute the effectiveness of exercise therapy for patients with neck pain, shoulder pain, repetitive strain injury, rheumatoid arthritis, asthma, and bronchiectasis. Exercise therapy is not effective for patients with acute low back pain. It is concluded that exercise therapy is effective for a wide range of chronic disorders.     

Changes to the subscales of two vision-related quality of life questionnaires are proposed

BACKGROUND AND OBJECTIVE: Psychometrically sound questionnaires for the assessment of vision-related quality of life (QOL) are scarce. Therefore, the objective was to further validate two vision-related QOL questionnaires in a Dutch population of visually impaired elderly. METHODS: A total of 329 visually impaired older persons referred to low vision services completed the low vision QOL (LVQOL) and Vision-Related Quality of Life Core Measure (VCM1) questionnaires at baseline, after 1-4 weeks (retest), and after 5 months. Confirmatory factor analyses were performed on baseline data. The smallest detectable change (SDC) was assessed, based on the standard error of measurement (SEM). Change scores between the baseline and 5 months follow-up data were related to a general transition question to assess the minimal important change (MIC). Furthermore, the MIC was related to the SDC, to examine whether the MICs were detectable beyond measurement error. RESULTS: The original factor structures could not be confirmed. After omitting items and remodeling, adequate fits were obtained. SDCs comprised at least one quarter of the scale for all scales and subscales on the individual level and exceeded the MICs on every occasion. CONCLUSION: We propose MICs of 5-10 points for the scales and subscales of the LVQOL and VCM1. The questionnaires are not useful in the follow-up of individual patients.     

Laparoscopic staging and subsequent palliation in patients with peripancreatic carcinoma

OBJECTIVE: To test the hypothesis that laparoscopic staging improves outcome in patients with peripancreatic carcinoma compared to standard radiology staging. SUMMARY BACKGROUND DATA: Diagnostic laparoscopy of peripancreatic malignancies has been reported to improve assessment of tumor stage and to prevent unnecessary exploratory laparotomies in 10% to 76% of patients. METHODS: Laparoscopy and laparoscopic ultrasound were performed in 297 consecutive patients with peripancreatic carcinoma scheduled for surgery after radiologic staging. Patients with pathology-proven unresectable tumors were randomly allocated to either surgical or endoscopic palliation. All others underwent laparotomy. RESULTS: Laparoscopic staging detected biopsy-proven unresectable disease in 39 patients (13%). At laparotomy, unresectable disease was found in another 72 patients, leading to a detection rate for laparoscopic staging of 35%. In total, 145 of the 197 patients classified as having "possibly resectable" disease after laparoscopic staging underwent resection (74%). Average survival in the group of 14 patients with biopsy-proven unresectable tumors randomly allocated to endoscopic palliation was 116 days, with a mean hospital-free survival of 94 days. The corresponding figures were 192 days and 164 days in the 13 patients allocated to surgical palliation. CONCLUSIONS: Because of the limited detection rate for unresectable metastatic disease and the likely absence of a large gain after switching from surgical to endoscopic palliation, laparoscopic staging should not be performed routinely in patients with peripancreatic carcinoma.     

Self-reported physical functioning was more influenced by pain than performance-based physical functioning in knee-osteoarthritis patients

BACKGROUND AND OBJECTIVES: To test the hypothesis that self-reported physical functioning is more influenced by pain than performance-based physical functioning. METHODS: 163 knee-osteoarthritis patients completed the performance-based DynaPort KneeTest (DPKT), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and SF-36 (self-report measures of pain and physical functioning) before, 3, 6, and 12 months after knee replacement. RESULTS: Correlations between (two) self-reported measures of functioning and (two) pain measures were higher (0.57-0.74) than correlations between the performance-based measure of functioning and the two pain measures (0.20 and 0.26). In factor analysis, WOMAC and SF-36 pain and physical functioning subscores loaded on the first factor (eigenvalue 3.2), while DPKT KneeScore2 loaded on the second factor (eigenvalue 0.92). Before surgery, correlations between performance-based and self-reported physical functioning were higher in patients with less pain (0.43) compared to patients with more pain (0.17), for the WOMAC (as expected), but not for the SF-36. After surgery, when the pain had diminished, the correlations between performance-based and self-reported physical functioning were higher, especially for the WOMAC. CONCLUSIONS: Our hypothesis was convincingly supported by the results of the WOMAC, and somewhat less by the results of the SF-36. We consider this as evidence for a lack of content validity of the WOMAC.