Table 3.

Characteristics of risk of bias tools and ad hoc criteria

Tool	Confounding	Bias in selection of participants into the study	Bias in classification of the exposure	Bias due to departures from intended exposures	Bias due to missing data	Bias in measurement of the outcome	Bias in selection of the reported results	Reporting quality	Generalisability	Precision/sample size	Other
Newcastle-Ottawa Scale38	X	X	X		X	X		X	X		Duration of follow-up
AHRQ Checklist for Cross-Sectional Studies60			X			X		X
Quality in Prognosis Studies61	X		X			X	X	X	X		Appropriateness of the statistical methods
ROBINS-I7	X	X	X	X	X	X	X
SIGN checklist for cohort studies62	X	X	X		X	X		X
SIGN checklist for case-control studies62	X	X	X		X	X		X
STROBE63								X
Cochrane risk of bias tool9		X		X	X	X	X
Critical Appraisal Skills Programme tools for cohort studies30	X		X		X	X		X	X	X	Magnitude of effect, Bradford-Hill Criteria
Data collection instrument and procedure for systematic reviews in the guide to community preventative services64	X	X	X	X		X		X			Appropriateness of the statistical methods, control for design effects, accounting for different levels of exposure in segments of the study population in the analysis
Effective Public Health Practice Project65	X		X	X	X	X			X		Appropriateness of the statistical methods
Mixed Methods Appraisal Tool66		X	X		X	X		X	X
NICE Methodological Checklist for Cohort Studies67	X			X	X	X					Duration of follow-up
NICE Methodological Checklist for Case-Control Studies67	X	X	X			X		X
NIH Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies31	X	X	X	X	X	X		X		X	Duration of follow-up
Quality Assessment Tool for Systematic Reviews of Observational Studies (QATSO)68	X					X			X		Privacy and sensitive nature of the question considered
Research Triangle Institute Item Bank on Risk of Bias69	X	X	X	X	X	X		X		X	Study design, prespecification of the outcomes, duration of follow-up, missing outcomes, appropriateness of statistical methods, believability of the results, reporting of funding
Ad hoc criteria
Theal et al. 201870 (combined two sets of ad hoc criteria)	X	X	X	X	X	X		X			Appropriateness of statistical methods
Beydoun et al. 201971	X					X				X	Study design
Gianfredi et al. 2018 Gianfredi et al. 201872 73	X	X	X		X	X
Asgari-Taee et al. 201874	X			X					X		Study design, appropriateness of statistical methods, validity of findings
Padilha et al. 201875	X
Dandamudi et al. 201876 (combined two sets of ad hoc criteria)	X	X	X	X
Dobbels et al. 201977			X	X	X	X		X		X
Dallacker et al. 201878			X			X			X		Study design

AHRQ, Agency for Healthcare Research and Quality; NICE, National Institute for Health and Care Excellence; STROBE, Strengthening the Reporting of Observational Studies in Epidemiology.