Abstract
To the Editor,
We read with great interest the recent systematic review and meta-analysis titled “Uniportal vs Biportal Endoscopic Decompression for the Treatment of Lumbar Spinal Stenosis: A Systematic Review and Updated Meta-Analysis” published in the Global Spine Journal. 1 The authors have contributed valuable insights into the comparative efficacy of minimally invasive spine surgery techniques.
However, we would like to respectfully raise a concern regarding the classification of 1 of the included studies: the work by Wu et al, 2 titled “Ambulatory uniportal vs biportal endoscopic unilateral laminotomy with bilateral decompression for lumbar spinal stenosis—a cohort study using a prospective registry.”
In the review, Wu et al’s study appears to be treated as a randomized controlled trial (RCT). However, upon examining the original publication, it is clearly described as a prospective cohort study utilizing registry data, and it does not involve formal randomization. This distinction is crucial, as RCTs provide a higher level of evidence and are typically associated with a lower risk of bias compared to observational designs.
Although the authors mention that patients were “assigned… using a random-number generator,” the study lacks other essential features of an RCT—such as trial registration, allocation concealment, and blinding. These are fundamental elements of randomized trial methodology, as outlined in established guidance such as the CONSORT statement and the Cochrane Handbook for Systematic Reviews of Interventions.3,4 Therefore, labeling it as a randomized trial may inadvertently overstate its methodological rigor.
This misclassification could potentially influence several aspects of the review, including meta-analytic weighting, risk of bias assessment, and the GRADE evaluation of the overall quality of evidence. We respectfully suggest that this issue be addressed in a corrigendum or carefully considered in future updates of the review.
We appreciate the authors’ contribution to the literature and hope this clarification will enhance methodological transparency in future evidence syntheses.
