The Skin Picking Scale: scale construction and psychometric analyses.

Area of Science:

• Psychiatry
• Psychometrics
• Behavioral Science

Background:

• Skin picking disorder is a significant concern.
• Existing assessment tools may not fully capture the severity of skin picking behaviors.
• A reliable and valid measure is needed for clinical and research settings.

Purpose of the Study:

• To develop and validate the Skin Picking Scale (SPS), a brief self-report measure.
• To assess the reliability and validity of the SPS in a clinical population.
• To establish a cutoff score for differentiating severity levels of skin picking.

Main Methods:

• Development of an initial eight-item scale based on the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS).
• Administration of the scale to 28 severe self-injurious and 77 non-self-injurious skin pickers.
• Psychometric analyses including internal consistency (Cronbach's alpha), construct validity (correlations with duration, BDI, BAI, emotional intensity), and receiver operating characteristic (ROC) analysis for cutoff determination.

Main Results:

• A six-item Skin Picking Scale (SPS) with a score range of 0-24 was finalized.
• The SPS demonstrated moderate internal consistency (Cronbach's alpha = .80).
• SPS scores significantly correlated with picking episode duration, depression (BDI), anxiety (BAI), and emotional intensity during picking.
• A cutoff score of 7 on the SPS effectively differentiated severe self-injurious from non-self-injurious skin pickers.

Conclusions:

• The Skin Picking Scale (SPS) is a valid and reliable self-report measure.
• The SPS is suitable for assessing skin picking severity in medical and psychiatric patients.
• The scale provides a useful tool for both clinical assessment and research purposes.