Dear Editor,
We thank the authors for showing great interest in our meta-analysis and putting forth their comments.[1,2] The hallucination estimate [odds ratio (OR) 12.73, 95% confidence interval (CI) 2.98–54.41] rests on data in which no control patient recorded an event in any of the four contributing arms. The Mantel–Haenszel fixed-effect method with a 0.5 continuity correction was pre-specified in our PROSPERO (International Prospective Register of Systematic Reviews) protocol and applied uniformly to every dichotomous outcome. Hence, it was retained in our study.
The Cochrane Handbook recommends the Peto method, where events are rare, arms are balanced, and the effect is moderate, roughly an OR of 0.2 to 5.[3] However, the ketamine-arm event rate in the study by Zhu et al.[4] lies well outside the recommended range. On doing sensitivity analysis, the pooled Peto OR is 8.42 (95% CI 3.47 to 20.42; P < 0.0001; I² =0%). The point estimate is lower and the interval narrower, but the direction, magnitude, and significance are unchanged. The present study[1] has considered this outcome in the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) profile, and the certainty of evidence was rated moderate rather than high.
Even though a low I² does not establish clinical homogeneity, the lack of an agreed definition of rebound pain (RP) is the main obstacle to pooling trials. The primary outcome pooled five trials, and the trial by Zhu and colleagues did not contribute to it.[4] The lack of standardised definitions of RP necessitates future trials to address the issue.
Disclosure of use of artificial intelligence (AI)-assistive or generative tools
Nil.
Conflicts of interest
There are no conflicts of interest.
Funding Statement
Nil.
REFERENCES
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