Measuring Disease specific impact and symptoms among patients with Hidradenitis Suppurativa


      Patients with Hidradenitis Suppurativa (HS) experience painful abscesses and nodules primarily in the skin flexures, along with other disease-related impact and symptoms, which can further diminish their health-related quality of life. No HS-specific tools exist to assess those symptoms and impacts. We aimed to report the development and initial psychometric evaluation of the Hidradenitis Suppurativa Symptom Assessment (HSSA) and the Hidradenitis Suppurativa Impact Assessment (HSIA).


      The HSSA and HSIA were developed based on a literature review and concept elicitation interviews with HS patients (n=20). Following initial construction, the questionnaires were cognitively debriefed among HS patients (n=20) to test their readability and comprehensiveness. Next, the HSIA and HSSA were implemented in a multi-center, non-interventional study with HS patients (n=40) to evaluate their item and scale score distributions and indices of reliability and validity.


      The literature review and input from patients indicates that HS is associated with a range of symptoms (e.g., pain, drainage, itchiness) and impacts (e.g., difficulty with movement and interference with sexual activities). These concepts were organized into a conceptual model to facilitate the construction of the questionnaires. Results from the cognitive interviews indicated that both the HSSA and HSIA are easily understood by patients and characterize their condition well. Forty subjects completed the observational study (females = 58%; Caucasian = 65%; and age [mean] = 41 years). The HSIA and HSSA scores were found to perform well psychometrically, with strong evidence of test-retest (ICC=0.92 and 0.80, respectively) and internal consistency (α=0.97 and 0.96, respectively) reliability and known groups (P<0.001 and P<0.006, respectively) and construct-related validity (via correlations between the target measures and other, concurrently administered tools).


      There is robust evidence supporting the HSIA and HSSA as content valid and psychometrically sound questionnaires for assessing symptoms and impacts in patients with HS.