We describe a comparison of the responsiveness of three validated instruments when used with patients undergoing coronary bypass surgery (CABG) and angioplasty (PTCA). Patients were randomly selected to receive the Coronary Revascularisation Outcome Questionnaire (CROQ), and either the Seattle Angina Questionnaire (SAQ), or the SF-36 before and 3 months after coronary revascularisation. At total of 199 patients (127 CABG, 72 PTCA) completed the CROQ; 55/72 CABG and 34/38 PTCA patients also completed the SAQ or SF-36, respectively. Effect sizes and standardised response means were calculated as change over the 3-month period for scales measuring similar constructs on each instrument. We used bootstrap estimation to derive 95% confidence intervals for differences in the responsiveness indices. For CABG, the CROQ demonstrated significantly greater change in psychosocial functioning than the SF-36, but less than the SAQ. For PTCA, the CROQ showed greater change for symptoms than the SAQ, but the SAQ was more responsive in terms of physical functioning; and the CROQ showed significantly greater change than the SF-36 for psychosocial functioning. There were no other significant differences between similar scales on the three instruments. In conclusion, the CROQ was as responsive as the disease-specific SAQ and more responsive than the generic SF-36.