OBJECTIVES: This study compared five methods of summarizing symptom data and the association of these measures with the outcome health related quality of life (HRQL) in patients who had experienced an acute coronary syndrome event (ACS). METHODS: All patients listed in an ACS registry (treated for ACS and discharged from a university affiliated hospital) during a 3 year period were mailed a questionnaire that assessed symptom status, demographics, cardiac functional status and therapy, comorbidity, ACS type and HRQL (SF-8 and EQ-5D).  The symptom survey included 24 symptoms and measured the occurrence, frequency, and distress associated with each symptom during the previous four weeks. Symptom summary measures included summed, averaged, and multiplicative (Symptom Product) values of each symptom characteristic.  Bivariate correlations and multivariate regression analysis were used to assess the association of each symptom summary measure with HRQL, controlling for other patient, disease, and treatment characteristics. RESULTS: A total of 490 of 1217 patients (40%) responded.  The mean age was 65.7±11.3 years; 67.7% male;94.0% Caucasian;PCS-8  53.7±10.5; MCS-8  49.5±9.5; and EQ-5D VAS 73.6±20.5.  The Symptom Sum=7.8± 4.9, Symptom Frequency Average=2.5± 0.72, Symptom Distress Average=2.2±0.8, Symptom Distress Sum =18.6±14.8, and Symptom Product=51.7±48.3.  Bivariate correlations demonstrated that the Symptom Sum and Symptom Product had the highest correlation (>0.54) with the HRQL domains, while Symptom Frequency Average was the lowest (0.24-0.33).  The same pattern was seen with the multivariate regression model. The model adjusted R-square for the Symptom Sum and Symptom Product measures were higher than the other measures, with the Symptom Product having the highest correlation.  The R-square values ranged for these two measures depending on the HRQL domain; PCS (0.38-0.44), MCS (0.33-0.35), EQ-5D (0.34-0.39). CONCLUSIONS: Researchers may consider using Symptom Sum or a Symptom Product measures when attempting to summarize the association of symptoms with HRQL in ischemic heart disease patients.