The Skin Picking Scale - Scale construction and psychometric analyses

Objective: This paper reports on the development of the Skin Picking Scale (SPS), a six-item paper-and-pencil measure for the assessment of skin picki ng. Methods: 28 severe self-injurious and 77 non-self-injurious skin picker s initially completed an eight-item severity scale modeled after the Yale-B rown Obsessive-Compulsive Scale (Y-BOCS). Results: Group comparisons and pa rt-whole correlations for individual scale items resulted in a six-item sca le with a total score range of 0-24. A Cronbach's alpha coefficient of .80 indicated moderate internal consistency for the scale. Construct validity w as demonstrated by significant correlations between SPS total scale scores and self-reported average duration of skin picking episodes. Significant co rrelations were also reported between SPS total scale scores and both Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI) scores, as well as self-reported intensity of emotions during the picking process. Lastly, sensitivity and specificity analyses suggest that a SPS cut-off score of 7 differentiates severe self-injurious and non-self-injurious skin pickers. Conclusion: The SPS is a valid and reliable self-report scale for the asses sment of severity in medical and psychiatric patients who endorse skin pick ing. (C) 2001 Elsevier Science Inc. All rights reserved.