Differences between volunteers and nonvolunteers in a high-demand self-recording study

Research combining time- or event-sampling techniques with diary methods in naturalistic settings has become increasingly popular in recent years. Advantages of such procedures include the enhancement of the ecological validity of the research as compared to traditional laboratory studies and the elimination of the bias in retrospective recall of traditional diary studies. However, such research places a relatively high demand on participants' time, effort, and willingness to self-report and self-disclose. To examine whether this demand influences the decision to volunteer, participants in a week-long Experience Sampling Method study were compared with persons who declined to participate. Potential differences between the groups were assessed for personality, adjustment, and demographic variables. Analysis indicated that the volunteers, as compared to the nonvolunteers, were less anxious, less likely to employ pathological defensive styles, and over-all were a better adjusted group. The results may reflect a tendency of more poorly adjusted individuals to avoid volunteering for research which they perceive may cause them to experience greater stress and anxiety.