Objective: To investigate study quality and reported prevalence among the emergent area of problematic Internet use (PIU) research conducted in populations of US adolescents and college students.

Data sources: We searched PubMed, PsycINFO, and Web of Knowledge from inception to July 2010.

Study selection: Using a keyword search, we evaluated English-language PIU studies with populations of US adolescents and college students.

Main outcome measures: Using a quality review tool based on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement, 2 reviewers independently extracted data items including study setting, subject population, instrument used, and reported prevalence.

Results: Search results yielded 658 articles. We identified 18 research studies that met inclusion criteria. Quality assessment of studies ranged between 14 and 29 total points of a possible 42 points; the average score was 23 (SD 5.1). Among these 18 studies, 8 reported prevalence estimates of US college student PIU; prevalence rates ranged from 0% to 26.3%. An additional 10 studies did not report prevalence.

Conclusions: The evaluation of PIU remains incomplete and is hampered by methodological inconsistencies. The wide range of conceptual approaches may have impacted the reported prevalence rates. Despite the newness of this area of study, most studies in our review were published more than 3 years ago. Opportunities exist to pursue future studies adhering to recognized quality guidelines, as well as applying consistency in theoretical approach and validated instruments.