Characteristics of participating and nonparticipating men in a randomized, controlled diet and exercise intervention trial.

OBJECTIVE

To study characteristics of importance for participation in a diet and physical exercise prevention programme.

SETTING

Primary Health Care, Sollentuna, and the Karolinska Hospital, Stockholm, Sweden.

SUBJECTS

A sample of 187 men, aged 35-60, with increased risk factors for CHD, were invited to a 6-month prevention programme. Participants (n = 158) were randomized into a diet group, a physical exercise group, a diet and physical exercise group, and a control group. Twenty-seven men, who declined participation, formed the group of nonparticipants.

DESIGN

Participants and nonparticipants were compared with respect to health beliefs, health knowledge, CHD risk factors, demographic and personality factors.

MAIN OUTCOME MEASURES

Characteristics of men participating and not participating in the intervention trial.

RESULTS

Nonparticipants, compared with participants, believed less in the benefits of dietary change and perceived the health threat of stroke and myocardial infarction as less serious. Nonparticipants had a better knowledge of a number of risk factors for cardiovascular disease.

CONCLUSION

Belief in treatment efficacy and perceived health threat, rather than health knowledge, predicted initial participation in a non-pharmacological intervention trial.