BACKGROUND: Coronavirus disease 2019 (Covid-19) is associated with diffuse lung damage. Glucocorticoids may modulate inflammation-mediated lung injury and thereby reduce progression to respiratory failure and death.
METHODS: In this controlled, open-label trial comparing a range of possible treatments in patients who were hospitalized with Covid-19, we randomly assigned patients to receive oral or intravenous dexamethasone (at a dose of 6 mg once daily) for up to 10 days or to receive usual care alone. The primary outcome was 28-day mortality. Here, we report the final results of this assessment.
RESULTS: A total of 2104 patients were assigned to receive dexamethasone and 4321 to receive usual care. Overall, 482 patients (22.9%) in the dexamethasone group and 1110 patients (25.7%) in the usual care group died within 28 days after randomization (age-adjusted rate ratio, 0.83; 95% confidence interval [CI], 0.75 to 0.93; P<0.001). The proportional and absolute between-group differences in mortality varied considerably according to the level of respiratory support that the patients were receiving at the time of randomization. In the dexamethasone group, the incidence of death was lower than that in the usual care group among patients receiving invasive mechanical ventilation (29.3% vs. 41.4%; rate ratio, 0.64; 95% CI, 0.51 to 0.81) and among those receiving oxygen without invasive mechanical ventilation (23.3% vs. 26.2%; rate ratio, 0.82; 95% CI, 0.72 to 0.94) but not among those who were receiving no respiratory support at randomization (17.8% vs. 14.0%; rate ratio, 1.19; 95% CI, 0.92 to 1.55).
CONCLUSIONS: In patients hospitalized with Covid-19, the use of dexamethasone resulted in lower 28-day mortality among those who were receiving either invasive mechanical ventilation or oxygen alone at randomization but not among those receiving no respiratory support. (Funded by the Medical Research Council and National Institute for Health Research and others; RECOVERY ClinicalTrials.gov number, NCT04381936; ISRCTN number, 50189673.).
Overall, 482 patients (22.9%) in the dexamethasone group and 1110 patients (25.7%) in the usual care group died within 28 days after randomization (age-adjusted rate ratio, 0.83; 95% confidence interval [CI], 0.75 to 0.93; P<0.001).
large randomized comparison with objective mortality ascertainment, near-complete follow-up, and consistent unadjusted sensitivity results
the use of dexamethasone resulted in lower 28-day mortality among those who were receiving either invasive mechanical ventilation or oxygen alone at randomization but not among those receiving no respiratory support
prespecified randomized subgroup comparisons support treatment selection, with an imprecise estimate in patients without respiratory support
In the dexamethasone group, the incidence of death was lower than that in the usual care group among patients receiving invasive mechanical ventilation (29.3% vs. 41.4%; rate ratio, 0.64; 95% CI, 0.51 to 0.81)
prespecified randomized subgroup comparison with a mortality estimate clearly favoring dexamethasone
However, there was no clear effect of dexamethasone among patients who were not receiving any respiratory support at randomization (17.8% vs. 14.0%; rate ratio, 1.19; 95% CI, 0.91 to 1.55).
randomized subgroup estimate supports uncertainty rather than equivalence, with its confidence interval allowing benefit or harm
Derived from the full evaluation — not a separate score.
Strengths
Concealed allocation and intention-to-treat analysis support the objective 28-day mortality comparison. Primary-outcome follow-up was complete for 99.9% of participants.
↳ Methods, Randomization and Statistical Analysis; Results, Patients
The randomized findings address an unresolved treatment question and identify benefit in ventilated and oxygen-supported patients. The conclusion retains the absence of demonstrated benefit without respiratory support.
↳ Introduction; Results, Primary Outcome; Abstract, Conclusions
The intervention uses a widely available medicine with a specified dose and duration. The Discussion reports adoption into UK practice and updated UK and US recommendations.
↳ Methods, Randomization; Discussion, paragraphs 2 and 4
Limitations
The report does not describe systematic broad adverse-event collection or analysis. Mortality and selected clinical outcomes therefore do not establish the full treatment safety profile.
↳ Methods, Outcome Measures; Results, Other Prespecified Clinical Outcomes
Respiratory-support subgroup findings are central to treatment interpretation, while reported P values are unadjusted for multiple testing. Prespecification and interaction or trend analyses mitigate but do not remove this limitation.
↳ Methods, Statistical Analysis; Results, Primary Outcome
The Discussion does not substantively compare all contemporaneous corticosteroid trials or fully trace the open-label and UK-only design constraints. Its subgroup-qualified conclusions and caution about other viral diseases nevertheless preserve important boundaries.
↳ Methods; Discussion
The large concealed randomized comparison, objective mortality endpoint, and near-complete follow-up support the central result. The disclosed age adjustment is accompanied by similar unadjusted sensitivity findings, while unadjusted subgroup testing warrants caution. Incomplete systematic nonfatal harms reporting limits the treatment assessment more than the small numeric and terminology differences limit interpretation. The Discussion places the result within heterogeneous glucocorticoid evidence and preserves the respiratory-support boundary, but offers less complete comparison with contemporaneous trials.
Nabu’s assessment, alongside the field’s view.
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Strong4.3
Confidence mediumThe trial resolves a documented therapeutic uncertainty with a large randomized mortality comparison. Respiratory-support-specific findings make the advance directly relevant to treatment selection.
Concealed allocation, objective mortality ascertainment, intention-to-treat analysis, and 99.9% follow-up support the execution assessment. Incomplete systematic nonfatal harms reporting is priced at 0.4 points, alongside consideration of unadjusted multiplicity and the disclosed later age adjustment.
The argument consistently distinguishes benefit with respiratory support from no demonstrated benefit without it. Numeric differences and final/preliminary terminology reduce precision without changing the central interpretation.
The paper engages heterogeneous glucocorticoid evidence, disease timing, possible no-support harm, and limits to extrapolation. Comparison with contemporaneous trials and tracing of design constraints remain incomplete.
Caveats4 of 4 checks
Ethics approval, consent, trial registration, protocol availability, and the funder role are declared. The Abstract describes final results while the Introduction and Discussion describe preliminary results.
Ethics approval: declared · Preregistration: declared
38 of 38 checkable references verified
40 references in manuscript 2 are books, websites or datasets — counted, but not index-checkable
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No retraction or expression of concern found in Crossref (includes Retraction Watch).
Sources: Crossref (incl. Retraction Watch) ✓
Where this paper’s evidence sits on the path from initial observation to real-world use.
A specified oral or intravenous regimen was tested within routine care across 176 NHS organizations. Limited broader implementation guidance and harms characterization temper otherwise direct actionability.
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