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Updated: Aug 14, 2026
An Experimental Paradigm for the Prediction of Post-Operative Pain (PPOP)
Published on: January 27, 2010
Deviations between registered protocols and published systematic reviews in high-impact anesthesiology and pain
Alessandro De Cassai1,2, Burhan Dost3, Nicole Asti4
1Department of Medicine-DIMED, University of Padua, Padua, Italy. alessandro.decassai@unipd.it.
Purpose:
Protocol registration is essential for preventing selective reporting bias in systematic reviews, yet deviations from registered protocols remain common across medical fields. We sought to evaluate the prevalence of protocol registration and assessed concordance between registered protocols and published systematic reviews in high-impact anesthesiology journals, hypothesizing that undeclared deviations would be prevalent.
Methods:
We conducted a cross-sectional analysis of systematic reviews published in 2025 in first-quartile anesthesiology journals according to Journal Citation Reports (Clarivate, London, UK). We searched PubMed® in July 2025 to identify eligible studies. Two reviewers independently assessed concordance between registered protocols and published reviews using a standardized 22-item extraction form covering eligibility criteria; the Population, Intervention, Comparison, Outcome, and Study Design (PICOS) framework; search methods; risk assessment tools; and planned analyses. We recorded agreement as binary outcome, with explicit acknowledgement of deviations noted.
Results:
Of 172 identified systematic reviews, we included 114 after excluding nonregistered studies and those with post hoc registration. All 114 (100%) reviews reported at least one protocol deviation, but only 18 (16%) provided justifications. The most frequent deviation was authorship change (74%), resulting in 317 additional authors without acknowledgement. PICOS framework variations occurred in 65% of reviews, with primary outcome changes in 15% (disclosed in only two cases). Search strategy deviations occurred in 28% of studies, and 38% added Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessments without prior registration.
Conclusions:
Our study identified at least one deviation from the registered protocol in all of the 114 included systematic reviews published in high-impact anesthesiology journals. Universal protocol deviations with minimal disclosure threaten the integrity of systematic reviews in anesthesiology and pain medicine. These findings show an urgent need for stricter protocol adherence and transparent reporting of deviations by authors, with enhanced oversight by peer reviewers and journal editors.
Study Registration:
Open Science Framework ( https://osf.io/ksezg ); first submitted 10 July 2025.