Reporting quality of animal research in journals that published the ARRIVE 1.0 or ARRIVE 2.0 guidelines: a cross-sectional analysis of 943 studies.

Background: The adherence to the Animals in Research: Reporting In Vivo Experiments (ARRIVE) guidelines across the journals that initially published the guidelines and if adherence has improved since the guidelines update, remains unknown. We aimed to quantify the level of adherence and analyze factors that might influence reporting quality among these journals.

Methods: This cross-sectional study retrospectively analyzed interventional animal experiments published in journals that released ARRIVE 1.0 and 2.0 guidelines in three periods: 5 years before (Pre-ARRIVE 1.0) and after (Post-ARRIVE 1.0) the publication of ARRIVE 1.0, and 1 year after the publication of ARRIVE 2.0 (Post-ARRIVE 2.0). Reviewers independently assessed adherence to the ARRIVE guidelines. Basic information and potential influencing factors were extracted. Adherence data were presented as frequency (percentages). Statistical factors influencing reporting quality were evaluated using the Chi-square test or Fisher's exact test.

Results: 215, 330, and 398 experiments were included during Pre-ARRIVE 1.0, Post-ARRIVE 1.0 and Post-ARRIVE 2.0 periods, respectively. None of the included 943 studies reported all 38 subitems, showing only 0%, 0%, and 0.25% studies had an "excellent" reporting quality across the three periods. The overall reporting quality was significantly improved among Pre-ARRIVE 1.0, Post-ARRIVE 1.0 and Post-ARRIVE 2.0 (P<0.001). The rate of studies with "average" reporting quality increased sequentially from 53.95% to 73.94% and then to 90.20%, and those with "poor" reporting quality decreased sequentially from 46.05% to 26.06% and then to 9.55% across the three periods. Specifically, 15 out of 38 (39.5%) subitems and 11 out of 27 (40.7%) similar and comparable subitems demonstrated a significant higher percentage of "fully reported" in Post-ARRIVE 1.0 compared to Pre-ARRIVE 1.0 and in Post-ARRIVE 2.0 compared to Post-ARRIVE 1.0, respectively (P<0.05). Country and journal indexing did not significantly affect reporting quality (both P>0.05). However, significant differences in reporting quality were found among the mandatory adherence to the ARRIVE guidelines in the author's instructions and reference to ARRIVE in the manuscript (both P<0.001).

Conclusions: In the journals that initially published the ARRIVE guidelines, compliance with the guidelines still has room for improvement, though it has increased sequentially since introducing the guidelines. Implementing mandatory adherence requirements in the author's instructions and explicitly recognizing adherence to ARRIVE in articles could enhance the reporting quality of interventional animal experiments.