Ego-strength, impulsiveness, and risk taking as personality correlates of volunteering

On the basis of a review of the literature, some tentative relationships between the traits of ego-strength, impulsiveness, and risk taking and the personality traits often associated with "volunteering behavior" were noted. These relationships suggested that the above mentioned personality traits might be predictive of subjects' volunteering for participation in research. or at least factors which should be considered when designating a research project in which volunteer bias is a possible problem. To test these possiblities, 350 students in introductory Psychology were administered the Barron Ego-strength Scale, the Barratt Impulsiveness Scale, the Kopan-Wallach Choice Dilomma Procedure for measuring risk taking. They were also given a series of opportunities to volunteer for participation as subjects in research projects. It was hypothesized that Volunteers would score higher on each of the three personality measures than would Non-Volunteers. When the male and female subjects were considered together, none of the Volunteer/Non-volunteer group differences were significant (p ranging from .10 to .20); however, the existing differences were in the hypothesized direction. Considering the sexes separately, however, did result in significant differences. Males evidenced higher Ego-strength scores than did females with Male Volunteers scoring significantly higher than any other group. In addition, whereas volunteering by males was predicted best by Ego-strength and then by Risk Taking, volunteering by females was best predicted by the measure of Impulsiveness. It is felt that these sex related differences between Volunteers and Non-Volunteers constitute important dimensions of volunteer bias and should be considered in teh design of experiments using volunteer human subjects.