A Method For Empirically Assessing Volunteer Selection Effects: Recruitment Procedures and Responses to Erotica

In this experiment we used a method that empirically assessed the effects of subject self-selection in laboratory research. Subjects were recruited for two "different" experiments (responses to erotica or personality questionnaires) and then exposed to the same procedures. The domain used to demonstrate this "different experiments" approach was sex research, and the substantive issue examined was whether men and women differ in their responses to erotica. In Part 1 of the study, all subjects answered questionnaires that assessed personality and demographic characteristics. In Part 2, subjects who agreed to watch an erotic movie (95% agreed) reported their reactions to it. The study indicated that conclusions about prior sexual experience, sexual opinions, and affective responses to the erotic film were qualified by recruitment condition. This experiment suggested that volunteer selection can have an important effect on experimental results, and it demonstrated a method for assessing the extent of these effects.