Trial reportDiving and hyperbaric medicine2025
Effect of normobaric and hyperbaric hyperoxia treatment on symptoms and cognitive capacities in Long COVID patients: a randomised placebo-controlled, prospective, double-blind trial.
Trial report in Diving and hyperbaric medicine, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
2 citing papers in PubMed.
- Hyperbaric Oxygen Therapy on Long COVID Symptoms: A Breath of Fresh Air.Diseases (Basel, Switzerland) · 2026Review
- Large-Scale Psychometric Assessment and Validation of the Modified COVID-19 Yorkshire Rehabilitation Scale Patient-Reported Outcome Measure for Long COVID or Post-COVID Syndrome.Journal of medical virology · 2026Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Introduction: Long COVID syndrome is a major health issue. Multiple treatments have been proposed but efficacy is inadequately investigated. Hyperbaric oxygen therapy (HBOT) has been promoted based on a small number of publications. As there is potential for a placebo effect and the financial cost of HBOT is high, we sought to investigate the effects of HBOT in Long COVID in a randomised trial. Methods: We randomised 101 patients into four treatment groups, receiving 10 sessions of oxygen 'treatment' inside a pressure chamber, according to one of four modalities: A - 100% oxygen at 253 kPa (2.5 atmospheres absolute); B - 40% oxygen at 253 kPa; C - 100% oxygen at 101.3 kPa (1 atmosphere absolute); D - 21% oxygen at 101.3 kPa. Groups B and C thus received a similar effective oxygen dose of 101.3 kPa. Quality of life symptom scores (Visual Analogue Scale; EQ-5D-5L, C19-YRSm), a 6-minute walking test and five neurocognitive tests were administered before and after the treatment series. At three months post-treatment, a telephone questionnaire probed for lasting effects. Results: All groups were comparable with regards to demographics, Long COVID symptoms and severity. After treatment, there were no significant differences in subjective symptoms, functional scores, and cognitive performance between any groups. The response to treatment was highly variable, with some patients in even the 'placebo' group D reporting a significant improvement in their well-being. This was not reflected in any objective outcome scores. No subgroups of patients responded better to any of the treatments. Conclusions: There was no significant effect from different doses of oxygen in a hyperbaric chamber. It is possible that the very modest improvements reported in other studies were due to a placebo effect. Claims that HBOT has a significant effect on Long COVID need further investigation before indiscriminately prescribing or promoting HBOT.
Indexed as
Identifiers
What Socratic holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.