Development and pilot-testing of a psoriasis screening tool

Area of Science:

• Dermatology
• Epidemiology
• Public Health

Background:

• Psoriasis self-report validation is crucial for epidemiological studies, especially when access to dermatologists is limited.
• Current methods may not accurately capture psoriasis prevalence in diverse populations.

Purpose of the Study:

• To develop and pilot test the Psoriasis Screening Tool (PST) for use in ambulatory settings.
• To assess the PST's efficacy in distinguishing individuals with and without psoriasis.

Main Methods:

• The PST was developed with eight yes/no questions and included typical psoriasis images.
• 222 dermatology clinic patients completed the PST, with diagnoses confirmed by a dermatologist.
• Sensitivity and specificity were calculated for the screening tool.

Main Results:

• A three-question combination achieved 96.4% sensitivity and 97.3% specificity for psoriasis.
• Including a pictorial question improved sensitivity to 98.2%.
• The PST identified various psoriasis phenotypes, including plaque, nail, scalp, and inverse involvement.

Conclusions:

• The PST effectively distinguishes individuals with psoriasis from those without in an English-speaking outpatient dermatology setting.
• The tool shows potential for identifying psoriasis phenotypes and collecting data in remote populations.
• While spectrum bias may be a limitation, the PST is considered a reliable tool for psoriasis information gathering.