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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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An observational atlas linked GLP-1 receptor agonists to dozens of outcomes beyond glucose, weight and the heart. We pooled the serious adverse events that 234 placebo-controlled trials, with 161309 participants, posted to ClinicalTrials.gov, coded blind to the results under a registered plan. Reports of serious bacterial infection (ratio 0.88, confidence interval 0.83 to 0.93) and pneumonia (0.87) were less frequent on the drugs, as were pneumonia counted in people and death. The reductions held under random effects, with any trial left out, if infection terms overlapped within participants as all serious events do in each comparison, and in trials not coded as recording only on treatment. Of the atlas's associations with enough events to test, the trials found three in its direction with no difference from it detected, contradicted none, and left most inconclusive, among them every neurological and psychiatric one; its large hazard of drug-induced pancreatitis concerns a subtype the trials don't separate.

• Published, Reproduced.Published, Reproduced: Of the 539 interventional studies of GLP-1 receptor agonists with results on ClinicalTrials.gov on 2026-10-12, 234 randomized trials compare a GLP-1 receptor agonist with placebo, in 257 comparisons with 161,309 participants in their adverse-event tables (93,765 on the drugs and 67,544 on placebo). In them, reports of serious gallbladder and biliary disease, counting a participant once for each of the outcome's terms they had, are more frequent on the drugs (Mantel-Haenszel ratio 1.38, 95% CI 1.21 to 1.57), and so are reports of serious nausea and vomiting (2.02, 1.52 to 2.68), as the trials' own publications and the drugs' labels lead one to expect.
• Published, Reproduced.Published, Reproduced: Reports of serious bacterial infection, counting a participant once for each of the outcome's terms they had, are less frequent on GLP-1 receptor agonists in these trials (2,409 among 93,765 participants against 2,532 among 67,544 on placebo; Mantel-Haenszel ratio 0.88, 95% CI 0.83 to 0.93, q < 0.001), and so are reports of serious pneumonia (1,442 against 1,568; 0.87, 0.81 to 0.93, q = 0.0020); both stay significant under random effects and with any single trial left out. Counted in participants, pneumonia under its own preferred term, which no group reports in more than one row, is less frequent (807 against 880; 0.86, 0.79 to 0.95). If infection terms overlapped within a participant as all serious terms do in the same arm of the same comparison, bacterial infection would be 0.89 (0.82 to 0.97).
• Published, Reproduced.Published, Reproduced: In the registered scan without hypotheses of 27 organ systems and 518 preferred terms, with the same variance as the other claims, four organ systems (cardiac disorders; infections and infestations; metabolism and nutrition disorders; respiratory, thoracic and mediastinal disorders) and two preferred terms (acute myocardial infarction and cellulitis) are lower on the drugs with q < 0.05 in a random half of the trials and p < 0.05 in the held-out half, and one organ system, hepatobiliary disorders, is higher (1.36 in the first half, 1.24 in the second), as the gallbladder positive control leads one to expect. Among those lower are serious infection reports as a whole (0.88 and 0.89) and cellulitis (0.64 and 0.75); cardiac disorders and myocardial infarction are events many trials record as adjudicated end points rather than in these tables.

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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.

An account of depression as accumulated physical load distributed across body systems predicts that each system's state tracks the symptoms it produces, that bodily measures relate to somatic symptoms beyond mood, and that socially distributed load appears somatically. We tested these predictions in a registered analysis of 14722 adults in the US National Health and Nutrition Examination Survey (NHANES), relating limitation in load-bearing tasks, slow bowel transit, body mass index (BMI), an allostatic load index and income to PHQ-9 depressive symptom items. Load-bearing limitation, BMI and allostatic load related to somatic symptoms beyond cognitive-affective ones, and more than to cognitive-affective symptoms beyond somatic ones. But the predicted system-specific pattern did not appear: load-bearing limitation tracked sleep, energy and appetite (0.2946) far more than slow transit did (0.0404). Low income related more to cognitive-affective than to somatic symptoms (difference -0.0996). Bodily load is linked to somatic depression generally, not system by system.

• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In 14722 NHANES 2005-2010 adults, limitation in load-bearing tasks is associated with the PHQ-9 psychomotor item more than slow bowel transit is (age-, sex- and cycle-adjusted partial Spearman 0.2038 vs 0.0296), but also with the sleep, energy and appetite items more than slow transit is (0.2946 vs 0.0404; difference -0.2542, 95% CI -0.2762 to -0.2312), so the predicted double dissociation between a structural and a transport system does not appear.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: Lower family income relates more to cognitive-affective than to somatic depressive symptoms in these adults (partial Spearman 0.1275 vs 0.0279; difference -0.0996, 95% CI -0.1299 to -0.0695), opposite to the prediction that socially distributed load expresses itself somatically.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In the same adults, load-bearing limitation, body mass index and a nine-marker allostatic load index are each associated with somatic depressive symptoms after adjusting for cognitive-affective symptoms (partial Spearman 0.1916, 0.0558, 0.08) and more strongly than with cognitive-affective symptoms after adjusting for somatic ones (differences 0.0711, 0.0399, 0.0646; Holm-adjusted p 0.002, 0.016, 0.002), whereas slow bowel transit shows no such specificity (difference 0.0074, 95% CI -0.0209 to 0.0347).

Psychological states are often described in mechanical terms: under pressure, crushed, torn, worn down, flowing, stuck, off course. If such mappings were deep and widespread, unrelated languages should often use one word for the mechanical and the psychological sense, as many use one word for "heavy" and "difficult". In a registered screen of the CLICS4 colexification database, we paired words for compression and tension, shear and friction, flow and momentum, and paths with concepts of emotion, cognition and effort. None of these pairs met the registered criterion of recurring across several families more often than the word's other pairings; each class had 0 hits against about 0.477 to 0.719 expected for random concepts. Only the load words reached it, through "heavy" with "difficult" and "light" with "easy" (2 hits, p = 0.0633). Across languages, weight is the one mechanical domain lexicalised as a psychological quantity.

• Published, Reproduced.Published, Reproduced: Across CLICS4 v1.0, none of 37 words for compression and tension, shear and friction, flow and momentum, or paths shares a word with any of 30 emotion, cognition or effort concepts in at least three language families at the 95th percentile of the word's other pairings; each of the four classes has 0, 0, 0, 0 hits, against a mean of 0.48 to 0.72 for random concept sets of the same size.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: Weight words are the exception: 'heavy' and 'light (weight)' give 2 hits among five load words (with 'difficult' and 'easy'), against 0.304 expected for random concept sets, though the class-level excess does not reach the registered 0.05 level (p = 0.0633), so the class test has limited sensitivity.

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).

Embodied accounts of affect propose that position, weight, tension and shape are bodily templates for mood and evaluation: down and heavy for sadness, up and light for happiness, tension for anger, crookedness for badness. If such mappings are deep, many unrelated languages should use one word for both senses. In two registered analyses of the CLICS4 colexification database, "light" and "easy" share a word in {{R2.pairs.LIGHT (WEIGHT)|EASY.families_colexifying}} of {{R2.pairs.LIGHT (WEIGHT)|EASY.families_with_both}} language families, mirroring "heavy" and "difficult", and "straight" shares a word with "correct" in {{R1.pairs.STRAIGHT|CORRECT (RIGHT).families_colexifying}} families. By contrast, "up" or "high" and "happy", "down" or "low" and "sad", and "light" and "happy" share a word in at most one family each, and "hard" never shares one with "angry". Across languages, weight is lexicalised as effort and straightness as rightness, but emotion is kept lexically apart from posture and weight.

• Published, Reproduced.Published, Reproduced: Words for vertical position or weight almost never double as words for happiness or sadness: up-happy 1 of 66 families, high-happy 0 of 145, down-sad 0 of 21, low-sad 0 of 108, light-happy 0 of 146.
• Published, Reproduced.Published, Reproduced: Hardness and softness, the nearest available proxies for tension and calm, do not double as words for anger or quietness: hard-angry 0 of 168 families, soft-quiet 2 of 154; 'tight' is covered in too few families to test.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: In CLICS4 v1.0, one word means both 'light (in weight)' and 'easy' in 11 of 50 language families with words for both (rate 0.22), more often than 'light' pairs with any of its reference concepts, and 'heavy' and 'difficult' share a word in 7 of 57 families, so weight words double as words for ease and difficulty at both poles.

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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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The World Health Organization's 2020 guideline recommended giving mass azithromycin, which lowers child mortality in high-mortality settings of sub-Saharan Africa, only to infants, to limit antibiotic resistance; no trial had then tested that. Under a pre-registered plan we pooled every randomized trial by whom it treated. Treating all children under five lowered their mortality by 14.1% (CI 7.4% to 20.3%), consistently across trials. In the three trials that treated only infants, infant mortality was not detectably lower (rate ratio 0.971, CI 0.867 to 1.086), an interval that excludes the effect of treating all children. Infants had lower mortality when all children were treated, though a between-trial comparison of the two strategies fell short of significance, and giving azithromycin to individual infants at clinic visits showed no effect. The infant-only approach has not lowered mortality in any trial that tested it; treating all children under five has.

• Published, Reproduced.Published, Reproduced: In the 3 cluster-randomized trials that gave azithromycin twice a year to infants 1 to 11 months old only, the approach the World Health Organization recommended in 2020 (AVENIR's infant arm in Niger, LAKANA in Mali, MIRAMA in Burkina Faso), infant mortality was not detectably lower than with placebo (rate ratio 0.971, 95% CI 0.867 to 1.086; p = 0.370), an interval that rules out a reduction larger than 13.3% and so excludes the 14.1% reduction seen when all children 1 to 59 months were treated; the estimate stayed near 1 with LAKANA's four-times-yearly arm instead (0.948, 0.856 to 1.050), without MIRAMA (0.963, 0.656 to 1.413), and with the 2 individually randomized infant trials added (0.969, 0.881 to 1.066).
• Published, Reproduced.Published, Reproduced: Giving azithromycin individually to every infant at a visit (the CHAT well-infant visit trial and NAITRE, both in Burkina Faso) did not detectably lower infant mortality: the pre-registered random-effects estimate from these 2 trials was uninformative (rate ratio 0.956, 95% CI 0.147 to 6.225), and a common-effect estimate added after registration was 0.963 (0.760 to 1.222).
• Published, Reproduced.Published, Reproduced: In 5 placebo-controlled comparisons from 3 cluster-randomized trials (MORDOR in Niger, Malawi and Tanzania; AVENIR in Niger; CHAT in Burkina Faso), twice-yearly mass azithromycin to every child 1 to 59 months old lowered mortality among children 1 to 59 months by 14.1% (rate ratio 0.859, 95% CI 0.797 to 0.926; Holm-corrected p = 0.015; I² = 0%), and the reduction held with a common-effect model (0.859, 0.813 to 0.908) and with any one comparison left out (largest p = 0.044).

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Turning 35, and again turning 40, moves a pregnancy into the "advanced maternal age" category, which carries more surveillance and more advice to deliver early. Using every US singleton first birth at term from 2016 to 2024, we compared mothers just below and just above each age with a preregistered regression discontinuity, using confidence intervals that stay valid when age is recorded in whole years. Labor induction jumps by 1.19 percentage points at 35 (honest 95% CI 0.7 to 1.68). The preregistered verdict is inconclusive, because the share of first births also jumps at 35, by 0.4 points. At 40, induction jumps by 2.86 points (2.05 to 3.67), and that secondary test meets its confirm rule. Delivery at 39 weeks rises at both ages. Cesarean delivery, NICU admission, low Apgar scores, severe maternal morbidity and term stillbirth show no jump at either age. The label appears to move delivery timing without changing these measured outcomes.

• Published, Reproduced.Published, Reproduced: Cesarean delivery, NICU admission, 5-minute Apgar below 7, and a maternal morbidity composite show no discontinuity at maternal age 35 (all honest 95% CIs within -0.52 to +0.76 percentage points) or at age 40 (all within -0.78 to +1.40 percentage points) among singleton first births at 37-44 weeks.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: Stillbirth at 37-44 weeks among singleton first pregnancies (fetal-death and natality files 2018-2024) shows no discontinuity at maternal age 35 (0.00 percentage points, honest 95% CI -0.22 to 0.23) or 40 (-0.03, honest 95% CI -0.29 to 0.24), intervals too wide to rule out effects of the size of the baseline rate.
• Published, Reproduced, Reviewed.Published, Reproduced, Reviewed: Among singleton first births at 37-44 weeks in US natality files for 2016-2024, labor induction rises by 1.19 percentage points at maternal age 35 (honest 95% CI 0.70 to 1.68, bias bound 0.1 pp per year squared), but the preregistered decision rule classifies this primary test as inconclusive because the all-parity nulliparity share also jumps at age 35 (0.40 pp, Holm-adjusted p = 0.023).

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