A cross-sectional bibliometric study showed suboptimal journal endorsement rates of STROBE and its extensions.

Objectives: The STrengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement provides guidance on reporting observational studies. Many extensions have been created for specialized methods or fields. We determined endorsement prevalence and typology by journals in extension-related fields.

Study Design And Setting: A published protocol defined search strategies to identify journals publishing observational studies (2007-2017) across seven fields relating to STROBE extensions. We extracted text regarding STROBE, seven STROBE extensions, reporting guidelines Consolidated Standards of Reporting Trials and Preferred Reporting Items for Systematic Reviews and Meta-Analyses, and transparent reporting documents/groups: International Committee of Medical Journal Editors, Committee on Publication Ethics (COPE), and the Enhancing the QUAlity and Transparency Of health Research (EQUATOR) networks. Relationships between endorsing STROBE, endorsing other guidelines, and journal impact factor were tested using chi square and Mann-Whitney tests.

Results: Of 257 unique journals, 12 (5%) required STROBE on submission, 22 (9%) suggested use, 12 (5%) recommended a "relevant guideline," 72 (28%) mentioned it indirectly (via editorial policies or International Committee of Medical Journal Editors recommendations), and 139 (54%) did not mention STROBE. The relevant extension was required by 2 (<1%) journals; 4 (1%) suggested use. STROBE endorsement was not associated with journal impact indices but was with Consolidated Standards of Reporting Trials and Preferred Reporting Items for Systematic Reviews and Meta-Analyses endorsements.

Conclusion: Reporting guideline endorsement rates are low; information is vague and scattered. Unambiguous language is needed to improve adherence to reporting guidelines and increase the quality of reporting.