Development and validation of a patient based measure of outcome in ocularmelanoma

Background-Patients with uveal melanoma can be treated by a number of modal ities. As none of the different treatments offer a survival advantage, a ke y factor in choosing among treatments is their differential impact on patie nts' quality of life. A short, patient based questionnaire was developed an d validated for evaluating outcomes following treatment for uveal melanoma. Methods-The 21 item measure of outcome in ocular disease (MOOD) assesses th e patient's view of outcome in terms of visual function and the impact of t reatment. The reliability and validity of the three MOOD scores (total, vis ion, impact) were evaluated in 176 patients who had been treated for uveal melanoma (75 brachytherapy, 78 proton beam radiotherapy, 23 enucleation). O f these, 165 patients also completed the SF-36. Results-All three MOOD scales met standard criteria for acceptability, reli ability, and validity. The proportion of missing data was low, and response s to all items were well distributed across response categories. Internal c onsistency, assessed by Cronbach's alpha coefficients, exceeded the standar d criterion of 0.70 for all three summary scores. Item total correlations r anged from 0.22 to 0.77 (mean item total correlation 0.58), indicating good homogeneity. Test-retest correlations for all three summary scores exceede d 0.85. Scaling assumptions, assessed by item convergent and discriminant v alidity correlations, were met for the vision and impact scores. The MOOD s howed good content validity, as assessed by review by ophthalmologists and patients. Construct validity was demonstrated by high intercorrelations bet ween the vision and impact scores and the total scale; higher scores for pa tients who reported being very satisfied compared with those who were not v ery satisfied and for those who reported persistent red eye compared with t hose who did not have this complication (known group differences/ hypothesi s testing); moderate correlations between the MOOD and the SF-36 and visual acuity (convergent validity); and low correlations between the MOOD and ag e and sex (discriminant validity). Conclusions-The MOOD is a practical and scientifically sound patient based measure which can be used in research and audit to evaluate outcomes follow ing treatment for uveal melanoma. It takes 5 minutes to complete and meets standard psychometric criteria for reliability and validity.