Validity assessment of the 10-Item Pruritus Severity Scale
Abstract
Introduction: A validated assessment of pruritus intensity is an important but still difficult clinical problem due to a subjective nature of this sensation. The aim of this study was the assessment of the reliability of a new 10-item Pruritus Severity Scale (10-PSS) developed based on the 12-Item Pruritus Severity Scale (12-PSS).
Material and methods: A total of 148 patients with pruritic dermatoses were asked to assess pruritus intensity using the 10-PSS and Visual Analogue Scale (VAS). In addition, 109 patients were also asked to complete the Dermatology Life Quality Index (DLQI). Test-retest comparison was conducted in 33 subjects who completed the 10-PSS twice with the 3- to 5-day interval. All results were analyzed statistically.
Results: We have created the new itch questionnaire (10-PSS) assessing pruritus intensity (two questions), pruritus extent (one question) and duration (one question), influence of pruritus on concentration and patient psyche (four questions), and scratching as a response to pruritus stimuli (two questions). The results showed strong internal consistency of 10-PSS (Cronbach α coefficient 0.81). A significant correlation was observed with VAS (r = 0.61, p < 0.001) and quality of life level according to DLQI (r = 0.46, p <0.001). The test-retest comparison in 33 subjects revealed a good reproducibility of achieved results (ICC = 0.81).
Conclusions: The 12-PSS and its shorter 10-item version are reliable methods of severity pruritus assessment and both may be used in daily practice and clinical studies.
Keywords: pruritusdisease severityassessment
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