MATERIALS AND METHODS: Mean SF-36 scores were calculated for 24 population subgroups (categorised by age, gender, ethnicity and questionnaire language) and for subjects with self-reported co-morbid conditions using data from a community-based survey in Singapore.

RESULTS: The English and Chinese SF-36 was completed by 4122 and 1381 subjects, respectively, 58% (n = 3188) of whom had self-reported co-morbid conditions. SF-36 scores varied in subgroups differing in age, gender and ethnicity. In general, subjects with self-reported co-morbid conditions had lower SF-36 scores than those without these conditions, the magnitude of which exceeded 20 points in several instances. A method for calculation of SF-36 scores adjusted for age, gender, ethnicity and questionnaire language is described.

PATIENTS AND METHODS: The validity and reliability of the Mal-HRQOL-20 were assessed in patients with and without lower urinary tract symptoms (LUTS). The reliability was evaluated using the test-retest method and the internal consistency using Cronbach's alpha. Sensitivity to change was expressed as the effect size in the score before and after intervention in additional patients with LUTS who underwent transurethral resection of the prostate.

RESULTS: The internal consistency was excellent; there was a high degree of internal consistency for each of the 20 items and for the overall score (Cronbach's alpha > or = 0.57 and 0.79, respectively) in the population study. The test-retest correlation coefficient for the 20 item scores was highly significant. The intra-class correlation coefficient was high (> or = 0.55). The sensitivity and specificity were high for the effects of treatment. There was a very significant agreement between scores before and after treatment across all domains in the treatment cohort, but not in the control group.