Blood donors registered in the Canadian Blood Services (n= 903).
Modified donor questionnaire that repositioned the men who have sex with men (MSM) question among neutral questions (n= 457).
Existing blood donor eligibility questionnaire (n= 446).
Participants who completed the existing donor eligibility questionnaire more strongly associated gay men with negative attributes on the sexuality implicit association test (IAT), suggesting question position generated implicit negative bias toward MSM. Responses to the Modern Homonegativity Scale - Gay Men (MHS-G) and prevalence estimation task indicated that question order had no significant impact on explicit bias.