Objective: This study aimed to evaluate the internal consistency reliability and construct validity of the Fitzpatrick Skin Type Scale during radiation therapy in a cohort of women receiving treatment for breast cancer.
Method: The assessment of the scale was performed as a nested study within a randomised controlled trial of two creams used for radiation therapy skin care for breast cancer patients. The sample consisted of 244 female patients undergoing radiation therapy for breast cancer. Participants completed a modified version of the Fitzpatrick Skin Type Scale.
Results: Internal consistency as measured by Cronbach's alpha was 0.505, 0.829 and 0.339 for the Genetic Disposition, Sun Exposure and Tanning Habits subscales respectively. Only the Sun Exposure subscale surpassed the 0.70 cut-off, indicating good internal consistency. Maximum likelihood factor analysis with promax rotation method confirmed the a priori factor structure for the Sun Exposure subscale as well as providing evidence of construct validity for this subscale. Analysis for the other two subscales highlighted issues with internal reliability and construct validity suggesting that not all items on each subscale truly measure the intended trait.
Conclusion: The study findings support reliability and validity of the Sun Exposure subscale of the Fitzpatrick Skin Type Scale in a convenience sample of women receiving radiation therapy for cancer. Despite limitations with two of the three subscales, this tool continues to be used in clinical practice.
Keywords: Fitzpatrick Skin Type Scale; reliability; validity.