Development and Validation of the Eyelash Satisfaction Questionnaire

Background: Patient-reported outcome (PRO) measures have been used to assess treatment benefit in a variety of therapeutic areas and are now becoming increasingly important in aesthetic research. Objectives: The objective of the current study was to develop and validate a new PRO measure (Eyelash Satisfaction Questionnaire [ESQ]) to assess satisfaction with eyelash prominence. Methods: The content of the questionnaire (including conceptual framework and questionnaire items) was generated by review of literature, participant interviews, and expert opinion. Cognitive interviews were conducted to pilot test the questionnaire. Psychometric properties of the questionnaire were ex-amined in a combined sample of participants (n = 970) completing Internet- (n = 909) and paper-based (n = 61) versions. Item- and domain-level prop-erties were examined using modern and classical psychometrics. Results: Content-based analysis of qualitative data demonstrated the presence of 3 distinct domains (Length, Fullness, Overall Satisfaction; Confidence, Attractiveness, and Professionalism; and Daily Routine). Initial confirmatory factor analysis (CFA) results of 23 items revealed insufficient model-data fit (comparative fit index [CFI] of 0.86 and a non-normed fit index [NNFI] of 0.82). A revised model using 9 items (3 per domain) achieved appropriate fit (CFI of 0.99 and NNFI of 0.97). Analyses revealed measurement equivalence across the Internet- and paper-based versions. The 3 ESQ domains had strong internal consistency reliability (Cronbach’s α [range] = 0.919-0.976) and adequate convergent and discriminant validity. Conclusions: The ESQ was found to be a reliable and valid PRO measure for assessing satisfaction with eyelash prominence