Health-related quality of life among adult HIV positive patients : assessing comprehensive themes and interrelated associations

Acknowledgements We would like to thank all HIV doctors, HIV nurses and clinical nurse specialists for their help with the inclusion of patients in the study. We are further grateful to all patients who filled out the questionnaires.Peer reviewedPublisher PD

Chapter 8: Meta-analysis of Test Performance When There is a “Gold Standard”

Synthesizing information on test performance metrics such as sensitivity, specificity, predictive values and likelihood ratios is often an important part of a systematic review of a medical test. Because many metrics of test performance are of interest, the meta-analysis of medical tests is more complex than the meta-analysis of interventions or associations. Sometimes, a helpful way to summarize medical test studies is to provide a “summary point”, a summary sensitivity and a summary specificity. Other times, when the sensitivity or specificity estimates vary widely or when the test threshold varies, it is more helpful to synthesize data using a “summary line” that describes how the average sensitivity changes with the average specificity. Choosing the most helpful summary is subjective, and in some cases both summaries provide meaningful and complementary information. Because sensitivity and specificity are not independent across studies, the meta-analysis of medical tests is fundamentaly a multivariate problem, and should be addressed with multivariate methods. More complex analyses are needed if studies report results at multiple thresholds for positive tests. At the same time, quantitative analyses are used to explore and explain any observed dissimilarity (heterogeneity) in the results of the examined studies. This can be performed in the context of proper (multivariate) meta-regressions

Assessment of the usefulness of a diagnostic test: A survey of patient preference for diagnostic techniques in the evaluation of intestinal inflammation

BACKGROUND: In order to assess the usefulness of radiolabeled white cell scanning in the diagnosis of intestinal inflammation, subjects were asked to rank several dimensions of preference for white cell scanning in relation to other diagnostic tests. Two groups were surveyed: one known to have inflammatory bowel disease and the second not familiar in most cases with the tests. Subjects were asked to rank preference for each of seven tests: radiolabeled white cell scan, colonoscopy, barium enema, sigmoidoscopy, enteroclysis, stool analysis and laparotomy for the diagnosis of IBD and impressions of discomfort, embarrassment, inconvenience and danger related to each test. Mean rank scores were calculated, test ranks compared within groups and significance determined by the Wilcoxon rank test. RESULTS: Significant differences were seen in overall preference for white cell scan over barium enema and colonoscopy (p < 0.01) in both survey groups. Perceived discomfort and embarrassment demonstrated similar rankings. CONCLUSION: This patient preference combined with the reported accuracy of white cell scanning further establishes the usefulness of this means of IBD diagnosis

Estimation of proteinuria as a predictor of complications of pre-eclampsia: a systematic review

Background Proteinuria is one of the essential criteria for the clinical diagnosis of pre-eclampsia. Increasing levels of proteinuria is considered to be associated with adverse maternal and fetal outcomes. We aim to determine the accuracy with which the amount of proteinuria predicts maternal and fetal complications in women with pre-eclampsia by systematic quantitative review of test accuracy studies. Methods We conducted electronic searches in MEDLINE (1951 to 2007), EMBASE (1980 to 2007), the Cochrane Library (2007) and the MEDION database to identify relevant articles and hand-search of selected specialist journals and reference lists of articles. There were no language restrictions for any of these searches. Two reviewers independently selected those articles in which the accuracy of proteinuria estimate was evaluated to predict maternal and fetal complications of pre-eclampsia. Data were extracted on study characteristics, quality and accuracy to construct 2 × 2 tables with maternal and fetal complications as reference standards. Results Sixteen primary articles with a total of 6749 women met the selection criteria with levels of proteinuria estimated by urine dipstick, 24-hour urine proteinuria or urine protein:creatinine ratio as a predictor of complications of pre-eclampsia. All 10 studies predicting maternal outcomes showed that proteinuria is a poor predictor of maternal complications in women with pre-eclampsia. Seventeen studies used laboratory analysis and eight studies bedside analysis to assess the accuracy of proteinuria in predicting fetal and neonatal complications. Summary likelihood ratios of positive and negative tests for the threshold level of 5 g/24 h were 2.0 (95% CI 1.5, 2.7) and 0.53 (95% CI 0.27, 1) for stillbirths, 1.5 (95% CI 0.94, 2.4) and 0.73 (95% CI 0.39, 1.4) for neonatal deaths and 1.5 (95% 1, 2) and 0.78 (95% 0.64, 0.95) for Neonatal Intensive Care Unit admission. Conclusion Measure of proteinuria is a poor predictor of either maternal or fetal complications in women with pre-eclampsia

Pharmacological treatment for psychotic depression

Background Evidence is limited regarding the most effective pharmacological treatment for psychotic depression: combination of an antidepressant plus an antipsychotic, monotherapy with an antidepressant or monotherapy with an antipsychotic. This is an update of a review first published in 2005 and last updated in 2009. Objectives 1. To compare the clinical efficacy of pharmacological treatments for patients with an acute psychotic depression: antidepressant monotherapy, antipsychotic monotherapy and the combination of an antidepressant plus an antipsychotic, compared with each other and/or with placebo. 2. To assess whether differences in response to treatment in the current episode are related to non-response to prior treatment. Search methods A search of the Cochrane Central Register of Controlled Trials and the Cochrane Depression, Anxiety and Neurosis Group Register (CCDANCTR) was carried out (to 12 April 2013). These registers include reports of randomised controlled trials from the following bibliographic databases: EMBASE (1970-), MEDLINE (1950-) and PsycINFO(1960-). Reference lists of all studies and related reviews were screened and key authors contacted. Selection criteria All randomised controlled trials (RCTs) that included participants with acute major depression with psychotic features, as well as RCTs consisting of participants with acute major depression with or without psychotic features, that reported separately on the subgroup of participants with psychotic features. Data collection and analysis Two review authors independently extracted data and assessed risk of bias in the included studies, according to the criteria of the Cochrane Handbook for Systematic Reviews of Interventions. Data were entered into RevMan 5.1. We used intention-to-treat data. For dichotomous efficacy outcomes, the risk ratio (RR) with 95% confidence intervals (CIs) was calculated. For continuously distributed outcomes, it was not possible to extract data from the RCTs. Regarding the primary outcome of harm, only overall dropout rates were available for all studies. Main results The search identified 3659 abstracts, but only 12 RCTs with a total of 929 participants could be included in the review. Because of clinical heterogeneity, few meta-analyses were possible. The main outcome was reduction of severity (response) of depression, not of psychosis. We found no evidence for the efficacy of monotherapy with an antidepressant or an antipsychotic. However, evidence suggests that the combination of an antidepressant plus an antipsychotic is more effective than antidepressant monotherapy (three RCTs; RR 1.49, 95% CI 1.12 to 1.98, P = 0.006), more effective than antipsychotic monotherapy (four RCTs; RR 1.83, 95% CI 1.40 to 2.38, P = 0.00001) and more effective than placebo (two identical RCTs; RR 1.86, 95% CI 1.23 to 2.82, P = 0.003). Risk of bias is considerable: there were differences between studies with regard to diagnosis, uncertainties around randomisation and allocation concealment, differences in treatment interventions (pharmacological differences between the various antidepressants and antipsychotics) and different outcome criteria. Authors' conclusions Psychotic depression is heavily understudied, limiting confidence in the conclusions drawn. Some evidence indicates that combination therapy with an antidepressant plus an antipsychotic is more effective than either treatment alone or placebo. Evidence is limited for treatment with an antidepressant alone or with an antipsychotic alone

Chapter 5: Assessing Risk of Bias as a Domain of Quality in Medical Test Studies

Assessing methodological quality is a necessary activity for any systematic review, including those evaluating the evidence for studies of medical test performance. Judging the overall quality of an individual study involves examining the size of the study, the direction and degree of findings, the relevance of the study, and the risk of bias in the form of systematic error, internal validity, and other study limitations. In this chapter of the Methods Guide for Medical Test Reviews, we focus on the evaluation of risk of bias in the form of systematic error in an individual study as a distinctly important component of quality in studies of medical test performance, specifically in the context of estimating test performance (sensitivity and specificity). We make the following recommendations to systematic reviewers: 1) When assessing study limitations that are relevant to the test under evaluation, reviewers should select validated criteria that examine the risk of systematic error, 2) categorizing the risk of bias for individual studies as “low,” “medium,” or “high” is a useful way to proceed, and 3) methods for determining an overall categorization for the study limitations should be established a priori and documented clearly

Chapter 1: Introduction to the Methods Guide for Medical Test Reviews

Evaluation of medical tests presents challenges distinct from those involved in the evaluation of therapies; in particular, the very great importance of context and the dearth of comprehensive RCTs aimed at comparing the clinical outcomes of different tests and test strategies. Available guidance provides some suggestions: 1) Use of the PICOTS typology for clarifying the context relevant to the review, and 2) use of an organizing framework for classifying the types of medical test evaluation studies and their relationship to potential key questions. However, there is a diversity of recommendations for reviewers of medical tests and a proliferation of concepts, terms, and methods. As a contribution to the field, this Methods Guide for Medical Test Reviews seeks to provide practical guidance for achieving the goals of clarity, consistency, tractability, and usefulness