To the Editor:

We read with interest the recent editorial by Eisenach et al.1  on the importance of reporting the a priori analysis plan of observational research. In a similar vein, clinical trialists are already very familiar with the need for prospectively registering randomized controlled trials (RCTs); indeed, if you have not registered the RCT, no major anesthesia journal is likely to publish the results. A key aspect of registration is its public accessibility that allows both the reviewer and reader to detect selective reporting, outcome switching, and data dredging. Some trial registries also have the capacity for researchers to upload the entire protocols and analysis plans, which further allows the reader to evaluate the veracity of the published work. Indeed, increasingly, RCT protocols are being published in dedicated journals well in advance of the eventual trial completion.

However, the standards for a priori reporting of protocols and analysis plans for observational studies have lagged those for RCTs. Eisenach et al.1  point out that some researchers do register their observational studies in trial registries, even though they are not RCTs per se; however, this is a relatively small proportion of observational studies. The change in policy of Anesthesiology outlined in the editorial now asks authors to indicate if they had an a priori analysis plan at all. Anesthesiology also strongly encourages researchers to develop a robust analytical plan and present it to a peer-review forum; however, these forums may not necessarily be public. While this is a step toward better reporting, and hopefully all anesthesia journals will follow their lead, it does ask the question as to why we should not expect the full analysis plans, or at the very least a summary, to be placed in a truly publicly accessible registry before analysis? This is not difficult to do with currently available registries (i.e.,, and it is possible that doing so further increases the veracity of the results.

Competing Interests

Dr. Davidson is Editor-in-Chief for Pediatric Anesthesia, and Dr. Grocott is Editor-in-Chief for Canadian Journal of Anesthesia.


Reporting of observational research in Anesthesiology: The importance of the Analysis Plan.