Evaluation of outcome measures for assessing problematic pornography use: A COSMIN systematic review of measurement properties

Problematic Pornography Use (PPU) is an increasingly recognized public health concern, with increasing evidence of its potential adverse consequences for individuals' psychological well-being, interpersonal relationships, and daily functioning. Accurate assessment of PPU is therefore essential for effective screening, diagnosis, and intervention. However, the field is characterized by a proliferation of outcome measures (OMs) with diverse theoretical foundations, inconsistent definitions, and limited cross-population validation. This systematic review was pre-registered in the PROSPERO database (CRD420251008765) and followed the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) Version 2.0 guidelines to identify, evaluate, and compare OMs used to assess PPU, as well as to offer recommendations for selecting appropriate OMs in research and clinical settings. A comprehensive search was conducted across four databases (MEDLINE, Web of Science, Embase, and PsycInfo) from database inception to February 28, 2025, with an additional supplementary search conducted on October 19, 2025. A total of 47 studies reporting on 24 OMs were included. While structural validity and internal consistency were frequently assessed, content validity, test-retest reliability, measurement error, and responsiveness were infrequently reported for most OMs. No single OM can be unequivocally recommended as the most appropriate instrument for assessing PPU in either clinical or research settings. Based on measurement property ratings and the overall quality of evidence, 19 OMs received Class-C recommendations, among which four OMs were considered the most promising (including the Problematic Pornography Use Scale, Problematic Pornography Consumption Scale PPCS, PPCS-6, and Brief Pornography Screen). Overall, these promising Class-C OMs may tentatively serve as valid and reliable tools for assessing PPU in clinical and research contexts, thereby providing a valuable resource for improving PPU assessment and informing evidence-based practice. Nevertheless, further studies are warranted to comprehensively validate the measurement properties of existing OMs. In addition, the findings underscore the importance of theory-driven and methodologically rigorous validation studies, as well as stricter adherence to COSMIN standards, to enhance consistency and comparability across studies.