Predicting participation in a dietary intervention to lower cholesterol among individuals with hyperlipidemia

Adult men and women (N = 8,748) were given blood cholesterol tests and completed a measure of fat intake and a staging questionnaire that assessed readiness to adopt a cholesterol-lowering diet. Eligibility for the trial was based on plasma cholesterol levels and self-reported dietary intake. Of 772 eligible participants, 545 (70.6%) agreed to join. In multivariate analyses, joiners did not differ from nonjoiners by age, total cholesterol levels, or self-reported dietary fat intake. Women were more likely than men to join the study. Individuals in the preparation stage (defined on the basis of a staging algorithm derived from the transtheoretical model of change) were more likely to join the trial than were precontemplators. An understanding of the determinants of participation in a dietary intervention may be important in the enhancement of high-risk individuals' acceptance of recommendations to make dietary changes.