How it departed

From its pre-registered plan, under plan/

• Done differently

  The plan uses a full text the library provides after registration only if it arrives before extraction. Nine more arrived after extraction had begun, for trials T004, T005, T006, T011, T015, T017, T019, T025 and T028, which had been coded and extracted from abstracts. They were used anyway, in the way the plan gives for earlier arrivals: each trial's design was coded again from its Methods by two new coders and a third reader (data/coding/design3; T017 became eligible), and its numbers were extracted again by two coders and a third reader (data/coding/extraction2), replacing the abstract-based ones. No outcome had been analysed unblinded when they arrived. data/trials.json and data/groups.json differ from plan/data/ for these nine trials only.

  Bears on C1, C2, C3, C4, C6, and C7

• Not stated

  The plan didn't say how a count of improvement enters. Fifteen counts of responders or remitters (in T025, T046, T093, T112 and T117), which the extractors' definitions name as such, run the other way from counts of participants with depression: their sign is turned so that negative g still means fewer depressive symptoms, and where a trial reports both kinds at one time, the count of participants with depression is used. The author marked each from its definition (data/annotations.json).

  Bears on C1, C2, C4, C5, C6, and C7

• Not stated

  Between-arm differences: the extractors kept a difference's estimate and interval on the entry rather than among its values, and the registered code read only the values; the analysis reads either. A difference is used only with its contrast (which arm is subtracted from which), which the author read from each source's wording (data/annotations.json: T069, T081, T084, T093, T117, T119); differences of changes from baseline (change_difference) are used as differences on the change scale.

  Bears on C1, C2, C4, C5, C6, and C7

• Not stated

  Forms the codebook didn't define but sources printed: a percentage of an arm with depression (converted to a count with the arm's n), a mean with a range (its SD estimated from the range by Wan et al. 2014), and a median with quartiles of a change from baseline (converted as medians of final values are). data/parameters.json adds them to the form order after the forms they resemble (mean_range after mean_ci, change_median_iqr after median_range, change_difference after difference, percent after count); plan/data/parameters.json is unchanged.

  Bears on C1, C2, C4, C5, C6, and C7

• Not stated

  A trial with several ketamine arms that reports only some of them at a time point (T088 on day 3) contributes the arms it reports there, combined; the registered code required every arm.

  Bears on C1, C2, C4, C5, C6, and C7

• Done differently

  Manipulation check: the registered code added an event's counts over the windows a trial reports (intraoperative, emergence, postoperative), which can count a participant twice and gave counts above an arm's size. The analysis takes the largest count over the windows, at most the arm's size.

  Bears on C3

• Not stated

  File drawer: a registration whose NCT number a review trial's Methods give counts as reported, though PubMed's index doesn't link the report to it (four: NCT03194594, NCT05506787, NCT06073015, NCT06920576).

  Bears on C6

• Not stated

  Reporting and an exploratory check, beyond the registered code: code/summarize.R writes the descriptive counts the paper gives (results/D.json) and, outside the plan, finds depression means with their SDs, as printed, that two different trials report on the same scale on the same day (shared_values); analyze.R writes each p value also as printed text and each effect's trial before T097 is split in two, and counts eligible trials before that split (the registered code counted T097's two comparisons as two trials); code/assemble_extraction.py rebuilds data/extraction.json from the coders' extractions in data/coding/. None of these changes an estimate.