Validity of Outcome Measures
APPENDIX
Since the outcome measures used in the present study (four-item PACS adapted for pornography use, I-PANAS-SF and 14-item WSWS adapted for pornography use) were not developed for the purpose of assessing pornography withdrawal-related symptoms, their structural and construct validity were briefly examined. First, confirmatory factor analyses were conducted on each baseline outcome measure to examine their factor structure in the present sample. Second, associations of the outcome measures with each other and with pornography use variables at baseline were examined to assess their convergent and discriminant validity. Results of these analyses are reported in detail in Appendix C and Tables S2-S5 in Supplementary Material. Overall, the outcome measures appeared to demonstrate adequate structural and construct validity for the purposes of the present study.