Item-Level Psychometric Properties for a New Patient-Reported Psoriasis Symptom Diary

Abstract

The 16-item Psoriasis Symptom Diary demonstrated favorable psychometric properties and is a brief, useful tool for measuring patient-based symptoms and the impact of chronic plaque psoriasis.

A systematic review of measurement properties of patient reported outcome measures in psoriatic arthritis: A GRAPPA-OMERACT initiative

“…[83][84][85][86] Nevertheless, our strategy ensures that the evidence obtained applies to patients with PsA as a whole.…”

Psychometric validation of the Psoriasis Symptom Diary using Phase III study data from patients with chronic plaque psoriasis

“…The PSD is a 16‐item, psoriasis‐specific PRO measure with a 24‐hour recall period (Table ) . A total of seven items evaluate the severity of the key signs and symptoms of plaque psoriasis, including psoriasis‐related itching (item 1), stinging (item 3), burning (item 5), pain from skin cracking (item 7), pain (item 9), scaling (item 11), and alterations in skin color (item 13).…”

“…To identify subjects who experienced a significant change in their disease state over the course of treatment and who reported that they responded to treatment, a threshold, or responder definition – characterizing a meaningful change in the scores of the measure – should be determined. For the PSD, Strober and colleagues used two methods recommended in the final PRO guidance to establish responder definitions: the anchor‐based method, and cumulative distribution function (CDF) plots depicting the range of the change in scores by treatment arm . The proportion of patients in the Phase III studies who achieved the thresholds previously identified from the Phase II data for the PGIC anchor “a little better” was computed, and the CDF plots were used to facilitate the evaluation of treatment response across a range of potential responder definitions.…”

“…Results determined that the PSD questions measure signs, symptoms, and impacts of plaque psoriasis that are relevant and important to patients; seven items address symptom severity, and nine items address symptom burden. Preliminary quantitative work was conducted using data collected from a Phase II study in patients with moderate to severe chronic plaque psoriasis . This prior research established sound initial estimates of the reliability, validity, and sensitivity to change of the 16 PSD items and provided thresholds for responder definitions of key PSD severity items for use in the evaluation of treatment efficacy.…”

“Bring Your Own Device” (BYOD): The Future of Field-Based Patient-Reported Outcome Data Collection in Clinical Trials?

“…Stable subjects during the 2-week period could be identified and the scores from the weekly intervals compared (using an intraclass correlation, for example). This approach is similar to how the test-retest reliability of a field-based ePRO assessment that is administered on the same dedicated device would be tested (see, eg, Strober et al 21 ).…”