Health related quality of life in patients with bladder cancer: a cross-sectional survey and validation study of the Hungarian version of the Bladder Cancer Index.

Health-related quality of life (HRQoL) is an important outcome in oncology care although an underexplored area in bladder cancer (BC). Our aims were to assess HRQoL of patients with BC, analyse relationships between diverse HRQoL measures and validate the Hungarian version of the Bladder Cancer Index (BCI) questionnaire. A cross-sectional survey was performed among patients with BC (N = 151). Validated Hungarian versions of the FACT-Bl, SF-36 and EQ-5D were applied and SF-6D was derived. Psychometric analysis of the Hungarian BCI was performed. Pearson correlations between the five measures were analysed. Deterioration in SF-36 Physical Functioning was detected among patients aged 45-64 years. The EQ-5D score did not differ significantly from the age-matched population norm. Correlations between the FACT-Bl, EQ-5D and SF-6D utility measures were strong (r > 0.6). Cronbach alpha coefficients of the Hungarian BCI ranged from 0.75 to 0.97 and factor analysis confirmed that data fit to the six predefined subdomains. Test-retest correlations (reliability, N = 50) ranged from 0.67 to 0.87 and interscale correlations between urinary, bowel and sexual BCI domains were weak or moderate (r = 0.29 to 0.49). Convergent validity revealed a stronger correlation with FACT-Bl (r = 0.126 to 0.719) than with generic health state scores (r = 0.096 to 0.584). Results of divergent validity of the Hungarian BCI by treatment groups by Kruskal Wallis test were promising although limited by low sample sizes in cystectomy subgroups. Generic health state measures have limited capacity to capture HRQoL impact of BC. Validity tests yielded favourable results for the Hungarian BCI. Mapping studies to estimate utility scores from FACT-Bl are encouraged but less recommendable with the BCI.