Development and validation study of the Smartphone Overuse Screening Questionnaire.

The aim of this study was to develop a screening questionnaire that could distinguish individuals at high risk of smartphone overuse from casual users. The reliability, validity, and diagnostic ability of the Smartphone Overuse Screening Questionnaire (SOS-Q) were evaluated. Preliminary items were assessed by 50 addiction experts on-line, and 28 questions were selected. A total of 158 subjects recruited from six community centers for internet addiction participated in this study. The SOS-Q, Young's internet addiction scale, Korean scale for internet addiction, and Smartphone Scale for Smartphone Addiction (S-Scale) were used to assess the concurrent validity. Construct validity was supported by a six-factor model using an exploratory factor analysis. The internal consistency and the item-total correlations were favorable (α = 0.95, r = 0.35-0.81). The test-retest reliability was moderate (r = 0.70). The SOS-Q showed superior concurrent validity with the highest correlation between the S-Scale (r = 0.76). Receiver operating characteristic curve analysis revealed an area under the curve of 0.877. A cut-off point of 49 effectively categorized addiction high-risk group with a sensitivity of 0.81 and specificity of 0.86. Overall, the current study supports the use of SOS-Q as both a primary and supplementary measurement tool in a variety of settings.