Library of risk of bias tools

Downs & Black Tool

Study design(s) targeted by the tool Randomized controlled trials (RCT)randomized-controlled-trial-rct Case-control studiescase-control-study Non-randomised studies of interventionsnrsi
Additional details on designs NA
Tool area Health
Link to the tool Access the paper reporting the Down & Black tool


Primary publication Downs SH, Black N. The feasibility of creating a checklist for the assessment of the methodological quality both of randomised and non-randomised studies of health care interventions. J Epidemiol Community Health 1998;52(6)
DOI 10.1136/jech.52.6.377
Guidance document

Additional guidance from author on Question 27: Downs and Black checklist – Q27 guidance

Language English

None known – please contact us if you are aware of any translations that should be listed here

Record last updated 15/08/2023

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Other publications

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Key Criteria

Focuses on risk of bias, or makes a distinction between items that assess risk of bias and other aspects of study quality Yes
Offers a method to reach either a domain specific or overall assessment of risk of bias Yes
Tool development involving a range of stakeholders from different disciplines (e.g. methodologists, statisticians, clinicians) No
Avoids recommending use of summary numerical quality scores No