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Evidence synthesis

This guide provides an overview of the evidence synthesis process

Risk of bias in studies (PRISMA Items 11 and 18)

Risk of bias assessment (sometimes called quality assessment or critical appraisal) helps to establish the certainty or strength of the evidence from the results and findings of a study. A risk of bias assessment is performed for each included study in your review.

There are a number of checklists available for different study designs including qualitative studies on the CASP website.

Critical Appraisal Skills Programme (CASP)

Cochrane Risk of Bias Tool (RoB 2 and RoB 1) for intervention studies, usually randomised controlled trials. The tool assesses domains such as selection, performance, detection, attrition and reporting biases.

Newcastle-Ottawa Scale for observational studies. Assesses selection bias, comparability and outcome domains.

QUADAS-C tool  for diagnostic test accuracy studies.

CEBM Critical appraisal tools

CASP Critical appraisal checklists

robvis visualisation tool

robvis is a web app designed to for visualizing risk-of-bias assessments performed as part of a systematic review.

robvis