Use patterns of outpatient cardiac rehabilitation services need to be identified, not as dichotomous measures of compliance-dropout, but as measures on a compliance continuum described by different levels of attendance. The authors investigated the associations between use of outpatient cardiac rehabilitation services (defined as attendance) and age, gender, the three major modifiable cardiovascular risk factors (smoking, hypercholesterolemia, and hypertension), reasons for referral, and different third-party reimbursement systems. The study population consisted of 492 patients (337 men, mean age, 58.8 years of age; 155 women, mean age, 57.0 years of age) who were referred to a 12-week hospital-based rehabilitation program after myocardial infarction (MI) (18.5%), coronary artery bypass surgery (CABG) (37.4%), bypass surgery plus infarction (CABG+MI) (13.4%), or other reasons (30.7%). Mean overall attendance was 75%. Survival analysis using the Cox proportional hazard regression model identified Medicaid /Title 19 as the factor most strongly associated with poor attendance (relative risk, 2.54; 95% confidence intervals, 1.76 to 3.67; P=0.000). Other factors with relative risk for poor attendance ranging from 1.86 to 1.43 included age (younger than 54 years of age), female gender, and other reasons for referral. Women younger than 45 years of age who receive reimbursement from Medicaid / Title 19, with a mean attendance of 18%, appear to be a high-risk group for poor attendance. Factors associated with attendance and compliance-enhancement warrant additional investigation as adequate use is critical for the effectiveness of cardiac rehabilitation services.