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Ketamine relieves depression within a day, but patients feel its psychoactive effects, so its benefit could depend on that experience. We asked whether ketamine and esketamine lower depressive symptoms when every dose is given under general anesthesia. Under a registered plan, we coded randomized trials' dosing from their Methods alone and pooled effects (Hedges' g) one to three days after surgery or childbirth. In 23 masked trials (3202 participants), depressive symptoms were lower with the drug than with an inert control (g -0.61, confidence interval -0.81 to -0.4; Holm-adjusted p < 0.001), though trials varied widely. Across trials in surgery, awake dosing did not show a larger effect (difference 0.12, -0.24 to 0.48), but this compares trials, and the one trial that randomized timing favored awake dosing. Masked doses also lowered pain. Ketamine can lower depressive symptoms after surgery without reaching an awake patient; whether experiencing the drug adds to that, these trials can't say. This version corrects counts, checks, and a reading that the first version's reviews found wrong.

• Published, Reproduced.Published, Reproduced: Among trials in surgery (37 comparisons: 22 masked, 15 with some dosing while patients were awake), trials that dosed patients while they were awake did not show a larger effect on depressive symptoms 1 to 3 days after surgery than masked trials: allowing for trials that enrolled only depressed patients, the coefficient of awake dosing in a meta-regression across trials was +0.12 (95% CI −0.24 to 0.48; p = 0.51), and the pooled effects in surgery were g −0.62 with masked and −0.45 with awake dosing. The comparison is between trials, which also differ in drug, dose, procedure, and patients, not between patients randomized to one timing or the other.
• Published, Reproduced.Published, Reproduced: In 23 randomized trials (3,202 participants) that gave every dose of ketamine or esketamine under general anesthesia, between its induction and the end of surgery or cesarean delivery, depressive symptoms 1 to 3 days after the procedure were lower than with an inert control (Hedges' g −0.61, 95% CI −0.81 to −0.40; Holm-adjusted p < 0.001), though the trials varied widely (95% prediction interval −1.51 to 0.29). The difference remained among the 17 of these trials that passed the pre-registered integrity screen (g −0.48, −0.63 to −0.33), among the 13 whose last dose is known to have ended more than 30 minutes before the end of surgery (g −0.67, −1.04 to −0.30), among the 19 whose doses all began after induction rather than with it (g −0.60, −0.85 to −0.36), and with any single trial left out (largest p < 0.001).
• Published, Reproduced.Published, Reproduced: The masked doses were pharmacologically active: masked ketamine lowered pain scores on day 1 or 2 after the procedure (g −0.55, 95% CI −0.97 to −0.14; 22 trials; g −0.38, −0.54 to −0.22 without the one trial whose printed dispersions can't be standard deviations), as awake ketamine did (g −0.33, −0.54 to −0.11; 32 trials; awake minus masked in surgery +0.32, −0.21 to 0.86). Masked ketamine still raised the odds of each trial's most frequent psychotomimetic adverse event (Mantel–Haenszel odds ratio 2.11, 1.48 to 2.99, in 22 trials), and awake ketamine raised them more (3.63, 2.97 to 4.43, in 40 trials): p = 0.0083 for the difference in the registered comparison, and p = 0.21 when the odds ratio may vary between trials (ratio of odds ratios 1.69, 0.74 to 3.84).

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Evidence that small fMRI studies overstate effects comes mostly from reported peaks, which are inflated by selection whatever the sample size. We asked the question with a whole-brain measure that has no peak selection. For each published (DOI-linked), group-level, unthresholded task-fMRI T or Z map on NeuroVault (Gorgolewski et al. 2015), we estimated the root-mean-square standardized effect over a fixed grey-matter mask from the mean squared statistic. We then regressed its log on log N with map-type, smoothing, upload-year and paradigm fixed effects plus a random intercept per collection. Everything was preregistered (prereg:f7ecdaf6…) on a frozen map list. After QC and de-duplication, 1245 maps from 200 collections were analysed. The slope was β = -0.101387 (CI -0.272087 to 0.069313), so the locked decision is inconclusive. There is no significant small-study inflation, and steep slopes are excluded. The data cannot rule out a modest slope at the preregistered boundary.

• Published, Reproduced.Published, Reproduced: Across 1,245 QC-passing, de-duplicated, published (DOI-linked) group-level unthresholded task-fMRI T/Z maps from 200 NeuroVault collections (N 10–1,369), the preregistered mixed model of log whole-brain rms standardized effect (grey-matter mask) on log N gives beta = -0.101387 (95% CI -0.272087 to 0.069313): no statistically significant small-study inflation of whole-brain effect sizes; slopes steeper than about -0.27 are excluded, but the preregistered refutation bound (-0.10) is not, so the locked decision is inconclusive.

Can simple daily sleep and positive-experience reports improve forecasts of emotional recovery beyond recent mood and stress? We fitted a fixed model in an earlier MIDUS daily-diary wave and evaluated it in held-out families there and in a later wave. The later-wave evaluation included 529 participants and 790 stressful days with elevated negative affect. Adding sleep duration and four common positive-event categories changed prediction error by -0.5602920767206551 percent in the improvement direction, with a conditional confidence interval from -1.4264876842069119 to 0.26668493108151836 percent. Thus the additional reports did not establish better predictions in this model. This does not show that sleep or pleasant experiences cannot help people recover. The plan was amended after a data-quality problem in an initial run; the amendment and original results are retained.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In an amended preregistered MIDUS prediction analysis, adding prior-night sleep duration and four-category positive-event history to a fixed mood-and-stress ridge baseline did not improve family-held-out next-day negative-affect predictions after elevated stressor days. In the later-wave transport test (529 participants,790 occasions), joint-model MSE was0.060283386 versus baseline0.059947505: percent MSE reduction -0.560292%, conditional family-bootstrap95%CI -1.426488% to0.266685%. Earlier-wave held-out reduction was -0.281695% (918 participants,1315occasions). These are performance estimates for the specified models, not causal effects or a general impossibility result.

This work tests a preregistered question on open New York City data: whether a fixed lag of CDC National Wastewater Surveillance System (NWSS) SARS-CoV-2 percentile predicts rises in confirmed COVID-19 cases better than the same-day percentile. The locked primary contrast is the difference in area under the receiver operating characteristic curve (AUROC) between a seven-day lag and a zero-day lag. On the pinned public snapshots, the lag-seven AUROC is 0.449326 and the lag-zero AUROC is 0.522145, so the delta is -0.07282 and the preregistered success flag false is false. The negative result is deterministic and re-run from code/analyze.py.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: Under the preregistered NYC analysis, the AUROC of a fixed 7-day lag of population-weighted CDC NWSS SARS-CoV-2 wastewater percentile for predicting a subsequent rise in NYC confirmed COVID-19 cases is 0.449326, which does not exceed the contemporaneous lag-0 AUROC of 0.522145 (delta -0.07282), so the locked success rule AUROC_lag7 > AUROC_lag0 fails.

Accounts that treat the felt weight of depression as more than metaphor rest on a premise: that distress is described in gravitational terms across unrelated languages. We tested a lexical form of that premise in a registered analysis of the CLICS4 database of cross-linguistic colexifications, asking whether languages use one word for "heavy" and for difficulty, grief, sadness or tiredness more often than for other concepts, and whether gravity-related words share words with sadness more than other physical-property words do. "Heavy" and "difficult" share a word in 7 of 57 families, more often than "heavy" pairs with any of its 1374 reference concepts, and "heavy" and "grief" in 2 families. "Heavy" never shares a word with "sad" (zero of 156 families) or "tired", and gravity-related words show no detectable excess with sadness (permutation p = 0.2232). Lexically, weight is widely the word for burden, not for sadness.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In the same data, 'heavy' never shares a word with 'sad' (0 of 156 families) or 'tired' (0 of 73), and 'sad' or 'grief' shares a word with any of 15 physical-property concepts in at most 2 families each, so gravity-related words (heavy, low, down) do not colexify with sadness detectably more than other physical-property words (difference in family-level rates 0.0031, one-sided permutation p = 0.2232).
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In CLICS4 v1.0 (3447 varieties, 247 families), a single word means both 'heavy' and 'difficult' in at least one language of 7 of the 57 families that have words for both (family-level rate 0.1228), higher than the rate for every one of 'heavy's 1374 reference partner concepts, whose 95th percentile is 0.0051; 'heavy' and 'grief' share a word in 2 of 69 families (rate 0.029, percentile 0.9964).

A regulated system nearing instability fluctuates more slowly, raising its lag-1 autocorrelation ("critical slowing down"). In a registered analysis of public sit-to-stand recordings from 27 adults, standing raised the autocorrelation of beat-to-beat systolic pressure by 0.0431 (CI 0.0066 to 0.0761). The rise was not larger with diabetes (probability of a larger rise 0.505, CI 0.2802 to 0.7308), and postural sway was not coupled to pressure beyond chance (median surrogate z -0.028). Standing shifts pressure dynamics toward slower fluctuations, but in this small sample the shift does not track diabetic status.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In the same recordings, the standing-induced rise in systolic-pressure lag-1 autocorrelation was not larger in 13 adults with type 2 diabetes than in 14 controls: the probability that a diabetic participant's rise exceeds a control's was 0.505 (bootstrap 95% CI 0.28 to 0.73; one-sided Mann-Whitney p = 0.49), which rules out only differences larger than that interval's upper end, since the test had 80% power only at a standardised difference of about 1.0.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: During eyes-open standing, magnitude-squared coherence in 0.05-0.15 Hz between anteroposterior whole-body sway acceleration (horizontal ground-reaction force over body weight) and beat-to-beat systolic pressure did not exceed phase-randomised surrogates: median surrogate z-score -0.03 across 26 participants, 2 of whom exceeded 1.645 (one-sided Wilcoxon signed-rank p = 0.54).
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In 27 adults from the PhysioNet Cerebral Vasoregulation in Diabetes sit-to-stand recordings, standing with eyes open raised the lag-1 autocorrelation of linearly detrended beat-to-beat systolic blood pressure relative to the preceding 240 s of sitting, by a Hodges-Lehmann shift of 0.043 (bootstrap 95% CI 0.007 to 0.076), with 19 of 27 participants rising (one-sided Wilcoxon signed-rank p = 0.012; Holm-adjusted across two primary tests p = 0.025).

Guaranteed income, regular cash with no conditions, has been tested in many American cities and in national pilots, and its advocates expect it to improve mental health without reducing work. We pre-registered a meta-analysis of randomized trials of flat, unconditional cash in high-income countries, searching databases, registries, and the reports most pilots publish outside journals; 62 trials were eligible and 53 had results. About a year into payments, mental health was better in the cash arms by 0.09 standard deviations (CI 0.041 to 0.139) across 34 comparisons in a random-effects model, but the common-effect estimate, which weights the largest trials most, was -0.002 (-0.023 to 0.018), and smaller trials reported larger effects. Employment changed by 0.599 percentage points (-2.533 to 3.731), and the mental-health effect did not fade during payments. Any mental-health benefit of guaranteed income is small and confirmed only in small trials, and about a year in it does not detectably reduce employment.

• Published, Reproduced.Published, Reproduced: In 14 comparisons from 13 randomized trials of recurring unconditional cash (9,623 people surveyed, and 175,222 in Finland's employment registers), the share of people employed about 12 months into payments did not detectably change: +0.60 percentage points (95% CI -2.53 to 3.73; Holm-corrected p = 1.000), an interval that rules out a reduction larger than 2.53 points; counting the share employed full-time where a trial printed no share employed at all, the change over 31 comparisons was +1.13 points (-1.14 to 3.40).
• Published, Reproduced.Published, Reproduced: In 19 comparisons of recurring unconditional cash with mental-health estimates at two waves during payments a mean of 11.7 months apart, the effect on mental health did not fade while payments continued: the pooled change from the earliest to the latest wave was 0.000 standard deviations (95% CI -0.049 to 0.048; Holm-corrected p = 1.000), the effects at the two waves being 0.048 and 0.061; across every wave during payments of 34 comparisons, the effect changed by +0.015 standard deviations per year (-0.034 to 0.064).
• Published, Reproduced.Published, Reproduced: One-time lump sums of unconditional cash, in 4 randomized comparisons with 19,907 people analysed, had no detectable effect on mental health at their latest follow-up within 12 months (standardized mean difference 0.009, 95% CI -0.025 to 0.043).

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