Leveraging real-world data in evidence-based caries research: a meta-epidemiological study

Leveraging real-world data (RWD) from dental records offers significant potential to overcome logistical and financial barriers in population-based caries research; however, comprehensive evaluations of such studies remain limited. This meta-epidemiological study systematically characterized the temporal and geographical distribution, study characteristics, and methodological quality of RWD-based caries research. A systematic literature search across MEDLINE, EMBASE, and Web of Science databases through December 2024 identified 230 eligible studies. Publication increased exponentially, with 57.8% published between 2015–2024, predominantly from Nordic countries (38.3%) and the United States (22.0%). Three-quarters were published in dental journals. About half used a cohort study design. Most studies (80.0%) used dental records from various sources. Over 25% had a sample size exceeding 10,000. Nordic studies frequently used public/school dental service records and, with larger samples, whereas U.S. studies primarily used university dental school records and focused more on adults and older persons. More association-based studies were published after 2015, with larger sample sizes. Nevertheless, 47.4% of studies inadequately reported caries examination methods, and only 8.7% reported agreement test results. Although use of multivariable regression for confounding adjustment increased markedly after 2015 (38.6% to 60.5%), causal inference frameworks and advanced analytic methods for confounding adjustment remained rare (4.4%) even among studies investigating causal relationships, and only 7.0% addressed missing data. RWD-based caries research has grown rapidly, but with notable methodological limitations, highlighting the urgent need for enhanced reporting standards, analytical rigor, and practical strategies to improve quality across diverse clinical settings and resource contexts.