Comparison of German language versions of the QWB-SA and SF-36 evaluating outcomes for patients with prostate disease

Background: The quality of well-being scale (QWB) and the Medical Outcome S tudy 36-item short form (SF-36) are alternative methods for measuring gener al health outcomes. Few studies compare these approaches against one anothe r and no studies have compared German language versions. Method: A German l anguage version of the self-administered quality of well-being scale (QWB-S A) was developed using forward and back translation methods. The German QWB -SA and a German language version of the SF-36 were administered to clinica l population groups with current diagnoses of prostate cancer, benign hyper plasia of the prostate, colon cancer, and rectal cancer. Data were obtained from four German clinics. In addition to the quality of life measures, dat a on cancer stage and disease state were obtained. Results: The QWB-SA and SF-36 were highly correlated. The QWB-SA was systematically related to dise ase state. Those with no symptomatic evidence had the highest scores follow ed by those who were stable with no metastatic disease and those with metas tatic progression. Similar patterns were found for most SF-36 scales althou gh the SF-36 failed to discriminate between those with no evidence of disea se and those with stable disease without metastasis. Conclusions: Both the QWB-SA and SF-36 perform as expected using German language translations. Al though both measures differentiate patients with metastasis from those with out symptoms, the QWB-SA better differentiated those with no evidence of di sease from those with stable disease without metastasis.