Measurement properties of the Patient-Reported Outcomes Information System (PROMIS® ) Itch Questionnaire: itch severity assessments in adults with atopic dermatitis.

Itch is the most common and burdensome symptom of atopic dermatitis (AD, also simply known as eczema). However, there is limited data to support the validity of different approaches to measure the severity of itch in AD, such as numeric rating scales (NRS), verbal rating scales (VRS), and frequency of itch. In this study, we set out to determine the measurement properties of the Patient-Reported Outcomes Information System (PROMIS® ) Itch Questionnaire (PIQ) itch severity assessment, including multiple NRS, VRS and frequency of itch assessments in adults with AD. We evaluated a group of 410 adults with AD who were patients at an academic medical center. We measured AD severity using multiple self and clinician-assessments. We used the PIQ itch severity scales to assess their itch severity. PIQ NRS, VRS and frequency of itch had good content validity (i.e. made sense to patients and were relevant to patient-experience in AD). PIQ NRS, VRS and frequency of itch showed good concurrent (i.e. correlated well with each other), convergent (i.e. correlated well with other measures of AD severity) and discriminant (i.e. scores were able to predict more severe AD) validity. PIQ NRS, VRS and frequency of itch also showed good measurement properties with respect to feasibility for use in clinical practice, reliability, and responsiveness. This suggests that PIQ NRS, VRS and frequency of itch have good validity for assessing itch in adults with AD. We recommend that clinicians screen all AD patients for itch severity. Linked Article: Silverberg et al. Br J Dermatol 2020; 183:891-898.