Dimensions of patient needs in dermatology: subscales of the patient benefit index.

Evaluation of patient-relevant treatment benefit gains importance for approval and reimbursement of therapeutic strategies. The 'Patient Benefit Index' (PBI) is the first questionnaire to measure patient-relevant treatment benefit in dermatology. Its global score is the average of benefits achieved after treatment, weighted by the individual importance of treatment needs. This study aimed to establish subscales of the PBI on the basis of independent and consistent treatment need dimensions. The PBI was used in a cross-sectional study involving n = 500 patients with ten distinct skin diseases, and in a longitudinal acne therapy study (n = 925). PBI dimensions were extracted by factor analysis and varimax rotation in both studies independently, using the longitudinal study data for replication. Factor analysis revealed largely similar need dimensions in both studies. The five-dimensional solution found in the cross-sectional study explained 63.0% of the variance. The need dimensions were named as reducing psychological impairments, reducing social impairments, reducing impairments due to therapy, reducing physical impairments, and building confidence into therapy. Using this factor solution, different patterns of need were found amongst the ten dermatological diseases. The PBI allows for a differential benefit assessment on five well distinguishable and interpretable subscales. The use of subscales as shown refines the interpretation of needs and benefits in dermatologic treatment.

The patient benefit index: a novel approach in patient-defined outcomes measurement for skin diseases.

Evaluation of therapeutic benefits from the patient's perspective is important in medical decision-making and reimbursement. This study aimed at developing and validating an instrument on patient-defined needs and benefits in dermatology. The questionnaire was developed according to international guidelines. The benefit assessment consists of two steps: before treatment, every patient defines his treatment needs according to a standardized list. After treatment, the patient rates the degree of benefits achieved. A "patient benefit index" (PBI) is calculated by averaging the preference-weighed results of all items. The PBI questionnaire was validated in a sample of 500 patients with ten skin diseases and in a treatment study on 906 patients with acne. The patients defined a broad spectrum of needs and treatment benefits, indicating disease-specific patterns. The PBI showed good feasibility, reliability (Cronbach's alpha >0.91) and construct validity, high responsiveness, and discrimination between subgroups. The PBI permits valid evaluation of patient-relevant benefits in dermatological treatment.