Table. 2—

Lewis Olds Williams scaling results for unintended methodological bias

	Babb [28]	Eves [29]	Johnson [30]	Laude [31]	Marciniuk [32]	Oelberg [33]	Palange [34]	Richardson [35]
Clear focus?	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Acceptable recruitment?	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Sample size justified?	No	No	Yes	Yes	Yes	No	No	No
Separate control groups?	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Well-matched control groups?	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
Baseline measures or self- controls?	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes
Bias minimisation for outcomes?	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Accounts for confounding issues?	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No
Results allow for self- determination of sample size	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes
Plausible results?	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Score	8	8	9	9	8	6	8	7