Hidradenitis Suppurativa Symptom Daily Diary (HSSDD) and Questionnaire (HSSQ): Psychometric Validation and...

Area of Science:

• Dermatology
• Clinical Trials
• Psychometrics

Background:

• Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition impacting patient well-being.
• Patient-reported outcome (PRO) tools like the HS Symptom Daily Diary (HSSDD) and HS Symptom Questionnaire (HSSQ) measure HS symptom severity.
• Validating these PROs is crucial for clinical trial assessment and patient care.

Purpose of the Study:

• To evaluate the psychometric properties of the HSSDD and HSSQ in patients with moderate to severe HS.
• To establish score interpretation thresholds for HSSDD and HSSQ to assess clinically meaningful improvements.
• To validate these instruments for use in clinical research and practice.

Main Methods:

• Pooled data from two Phase 3 HS trials (BE HEARD I & II) were analyzed.
• Psychometric properties including test-retest reliability, convergent validity, known-groups validity, and responsiveness were assessed.
• Clinically meaningful improvement thresholds were estimated using anchor- and distribution-based analyses.

Main Results:

• HSSDD and HSSQ demonstrated good test-retest reliability (ICC: 0.73-0.86) and convergent validity.
• The instruments effectively discriminated between patient subgroups, confirming known-groups validity.
• Responsiveness was established through correlations with anchor measures, and interpretation thresholds were defined.

Conclusions:

• The HSSDD and HSSQ exhibit strong psychometric performance for assessing HS symptom severity.
• The established interpretation thresholds provide a basis for evaluating treatment efficacy in moderate to severe HS.
• These validated PRO tools can aid in the assessment of HS patients in clinical trials and practice.