The Influence of Bias in Randomized Controlled Trials on Rehabilitation Intervention Effect Estimates: What We Have Learned from Meta-Epidemiological Studies

Arienti, C
Armijo-Olivo, S
Ferriero, G
Feys, P
Hoogeboom, T
Kiekens, C
Lazzarini, SG
Minozzi, S
Negrini, S
Oral, A
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Journal Article
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Edizioni Minerva Medica

This study aimed to synthesize evidence from studies that addressed the influence of bias domains in randomized controlled trials on rehabilitation intervention effect estimates and discuss how these findings can maximize the trustworthiness of an RCT in rehabilitation. We screened studies about the influence of bias on rehabilitation intervention effect estimates published until June 2023. The characteristics and results of the included studies were categorized based on methodological characteristics and summarized narratively. We included seven studies with data on 227,806 RCT participants. Our findings showed that rehabilitation intervention effect estimates are likely exaggerated in trials with inadequate/unclear sequence generation and allocation concealment when using continuous outcomes. The influence of blinding was inconsistent and different from the rest of medical science, as meta-epidemiological studies showed overestimation, underestimation, or neutral associations for different types of blinding on rehabilitation treatment effect estimates. Still, it showed a more consistent pattern when looking at patient-reported outcomes. The impact of attrition bias and intention to treat has been analyzed only in two studies with inconsistent results. The risk of reporting bias seems to be associated with overestimation of treatment effects. Bias domains can influence rehabilitation treatment effects in different directions. The evidence is mixed and inconclusive due to the poor methodological quality of RCTs and the limited number and quality of studies looking at the influence of bias and treatment effects in rehabilitation. Further studies about the influence of bias in RCTs on rehabilitation intervention effect estimates are needed.

Participants in the 5th Cochrane Rehabilitation Methodological Meeting , 4202 Epidemiology , 42 Health Sciences , Rehabilitation , Behavioral and Social Science , Clinical Research , Clinical Trials and Supportive Activities , 8 Health and social care services research , 8.4 Research design and methodologies (health services) , 1103 Clinical Sciences , 1106 Human Movement and Sports Sciences , 1117 Public Health and Health Services , Rehabilitation , 4201 Allied health and rehabilitation science , 4203 Health services and systems
European Journal of Physical and Rehabilitation Medicine, ISSN: 1973-9087 (Print); 1973-9095 (Online), Edizioni Minerva Medica, 60(1), 135-144. doi: 10.23736/S1973-9087.23.08310-7
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