OBJECTIVES:  Treatments to prevent prostate cancer are associated with side effects and the impact of these on health related quality of life (HRQL) should be considered in any assessment of cost effectiveness.  However our systematic review identified a lack of robust data.  A prospective assessment of the impact of side effects was undertaken using generic and condition-specific measures of HRQL.  METHODS: Participants were recruited from an online panel.  Men over 55, with either erectile dysfunction (ED), loss of libido, gynecomastia or ejaculatory disorders (without other chronic disease such as renal failure, diabetes, multiple sclerosis etc), and an age matched control group completed assessments of symptom severity and HRQL (EQ-5D and Sexual QoL survey – SQoL-3D).  Both HRQL measures can provide utility estimates.  Regression models (tobit, OLS, Censored least absolute deviation) were used to estimate specific changes in HRQL associated with the side effects.  RESULTS: Many participants reported more than one symptom, with ED most common (n=139); reduced libido (n=99); ejaculatory disorder (n=98), and gynecomastia (n=20).  From the OLS regression EQ-5D and SQoL-3D disutilities were estimated for ED (-0.042; -0.075); reduced libido (-0.053; -0.047); ejaculatory disorder (-0.046; -0.028), and gynecomastia (-0.045; -0.037) respectively.  EQ-5D and SQoL-3D were weakly correlated (r=0.296).  CONCLUSIONS: The condition-specific and generic estimates indicate the impact of prostate-related preventative treatment on HRQL.  While the magnitude of disutilities is similar the poor correlation between the two measures suggests they are measuring different aspects of HRQL.  The value of condition-specific versus generic methods for estimating utilities will be discussed.