ABSTRACT
The aim of this article was to perform a scoping review of methods available for dealing with confounding when analyzing the effect of health care treatments with single-point exposure in observational data. We aim to provide an overview of methods and their performance assessed by simulation studies indexed in PubMed. We searched PubMed for simulation studies published until January 2021. Our search was restricted to studies evaluating binary treatments and binary and/or continuous outcomes. Information was extracted on the methods' assumptions, performance, and technical properties. Of 28,548 identified references, 127 studies were eligible for inclusion. Of them, 84 assessed 14 different methods (ie, groups of estimators that share assumptions and implementation) for dealing with measured confounding, and 43 assessed 10 different methods for dealing with unmeasured confounding. Results suggest that there are large differences in performance between methods and that the performance of a specific method is highly dependent on the estimator. Furthermore, the methods' assumptions regarding the specific data features also substantially influence the methods' performance. Finally, the methods result in different estimands (ie, target of inference), which can even vary within methods. In conclusion, when choosing a method to adjust for measured or unmeasured confounding it is important to choose the most appropriate estimand, while considering the population of interest, data structure, and whether the plausibility of the methods' required assumptions hold.
Subject(s)
Research , Humans , Computer Simulation , BiasABSTRACT
ABSTRACT: Nonpharmacological interventions are recommended for the treatment of fibromyalgia, but there is a lack of knowledge about the cost-effectiveness of these interventions. The aim of this study was to systematically review economic evaluations of educational, physical, and psychological interventions for the treatment of fibromyalgia. The search was performed in PUBMED, EMBASE, CINAHL, Cochrane Library, Physiotherapy Evidence Database, PsycINFO, EconLit, National Health Service Economic Evaluation Database, and Health Technology Assessment. Economic evaluations of educational, physical, and psychological interventions for adult patients with fibromyalgia were included. Primary outcomes were healthcare and societal costs, and quality-adjusted life-years, and secondary outcomes were any disease-specific clinical outcome. Costs and effects were pooled in a meta-analysis, when possible. Eleven studies were included, of which 7 compared a psychological intervention with another intervention or usual care/control. Over a 6-month time horizon, healthcare and societal costs of the psychological intervention were significantly lower than usual care (mean difference: $-2087, 95% confidence interval [CI]: -3061 to -1112; mean difference: $-2411, 95% CI: -3582 to -1240, respectively), and healthcare costs were significantly lower for the psychological intervention compared with a pharmacological intervention (mean difference: $-1443, 95% CI: -2165 to -721). Over a 12-month time horizon, healthcare costs for the psychological intervention were significantly lower than for usual care (mean difference: $-538, 95% CI: -917 to -158). Incremental cost-effectiveness ratios for quality-adjusted life-years and impact of fibromyalgia showed that the psychological intervention was cost-effective compared with other interventions and control conditions. There is a need of more economic evaluations conducted alongside randomized controlled trials with interventions recommended for the treatment of fibromyalgia, such as physical exercise.
