[Reporting quality of online surveys using internet panels: A literature review using Ichushi-Web and evaluation of...

Objectives　To assess whether articles indexed in the Ichushi-Web database that report online surveys using internet panels provide sufficient methodological information to facilitate appropriate interpretation and evaluate the overall quality of reporting.Methods　We operationally defined online surveys using internet panels as cross-sectional or longitudinal online surveys conducted among registered monitoring populations. Based on existing reporting guidelines, namely the Checklist for Reporting Results of Internet E-Surveys (CHERRIES) and the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement, we developed 17 evaluation items considered essential for reporting surveys using internet panels. A literature search for original articles published between 2020 and 2024 was conducted using Ichushi-Web, the online search service of the Japan Medical Abstracts Society. Two researchers independently screened titles and abstracts in the first stage, followed by full-text screening by four researchers to identify articles reporting online surveys using internet panels. Four researchers independently evaluated the included articles using predefined evaluation items, and the results were aggregated and analyzed.Results　In total, 165 articles were included in the analysis. General reporting items such as the study period, study population, and ethical approval were adequately reported in most articles. In contrast, only a few articles explicitly stated in the title or abstract that the survey was conducted using an internet panel. Moreover, the key items essential for evaluating reporting quality and transparency, including the participant selection flowchart and information on incentives, were not reported in most articles. The number of invited participants, the number of respondents, the response rate, and the sample size were evenly divided between generally appropriate and not reported. Although the names of survey companies were reported in some articles, the information necessary to assess representativeness, such as the characteristics of the internet panel or the eligibility criteria for panel registration, was rarely provided.Conclusion　Many articles identified through Ichushi-Web that reported online surveys using internet panels lacked critical information necessary to evaluate reporting quality and transparency, particularly regarding panel characteristics and potential sources of bias. This study provides an important foundation for organizing reporting items specific to surveys using internet panels and for the future development of reporting guidelines.