Assessing the Value of Supportive Skin Care: Development and Validation of an Instrument for Evaluating Patient-Relevant Benefit

Background: Supportive skin care for irritated and inflamed skin is one of the most important measures in the prevention and treatment of eczema and sensitive skin. Objectives: To develop and validate an instrument for the evaluation of patient-relevant benefit in the supportive care of irritated skin with nonpharmacological topical agents. Methods: Patient-defined treatment objectives and benefits of supportive skin care were determined in an open survey of patients with irritated skin. A pilot questionnaire was constructed according to the Patient Benefit Index (PBI). The questionnaire was tested for feasibility and validity in 1,886 patients with various irritated skin conditions. Results: From a total of 90 characteristics of basic therapy benefit, a 23-item questionnaire was constructed. This questionnaire (‘PBI-k’) proved to be feasible, reliable and was associated with a high level of patient acceptance in the surveillance field. The questionnaire showed good internal consistency, distribution characteristics and convergent validity with patient satisfaction. Conclusion: The PBI-k is the first specific instrument developed for the evaluation of patient-defined benefit in supportive skin care with nonpharmacological topical agents. Feasibility and psychometric properties make this questionnaire suitable for application in studies involving patients with irritated, sensitive skin.