Development and validation of a questionnaire to evaluate how a cosmetic product for oily skin is able to improve well-being in women

BACKGROUND: Skin diseases are known to negatively affect self-image and to have detrimental psychosocial effects. Oily skin is a cosmetic skin problem that women often describe as 'invalidating'. OBJECTIVE: To develop and validate a questionnaire to assess the psychological and psychosocial effects of oily skin condition in women and the outcome of a targeted cosmetic skincare treatment. METHODS: We developed and validated a concise 18-item questionnaire [oily skin self-image questionnaire (OSSIQ)] to assess perception, behavioural, and emotional consequences associated with oily skin condition. The questionnaire was then used to assess the effects of a skincare treatment for oily skin and compare them with sebum level measurements. RESULTS: The 18-item questionnaire clearly distinguished the oily skin group from the control group. Responsiveness, reliability, and construct validity showed satisfactory performance. The questionnaire provided a relevant assessment of the psychological benefits associated with the skincare programme. CONCLUSION: The OSSIQ is a valid tool that can be used to monitor the benefits of cosmetic skincare treatments.