Table 1.

Prevalence of manipulation checks of different types in various psychology journals from January 2015 to February 2016.

	JEP: Gen	PS	JPSP: ASC	PSPB	JESP	Total
Number of empirical papers	110	194	35	140	135	614
Number (%) with at least one manipulation check	24 (22%)	29 (15%)	22 (63%)	58 (41%)	71 (53%)	204 (33%)
Number (%) that had a verbal manipulation check	21 (19%)	24 (12%)	19 (54%)	55 (39%)	69 (51%)	188 (31%)
Number (%) that had a verbal manipulation check and did not manipulate question order	19 (17%)	21 (11%)	19 (54%)	52 (37%)	69 (51%)	180 (29%)