ArticleBMJ open2026
Measuring the carbon footprint of clinical research activities: a scoping review of measurement tools and methods.
Article in BMJ open, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
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
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundHealthcare contributes substantially to global greenhouse gas emissions; however, the environmental impact of clinical research activities remains poorly understood. Quantifying emissions is a necessary first step toward reducing the carbon footprint of research.
objectiveTo map and synthesise literature measuring carbon emissions associated with clinical research activities, with a focus on research domains assessed, tools and methods used and units of measurement reported.
methodsA scoping review was conducted following the Arksey and O'Malley methodology and Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews guidance. PubMed, Web of Science, CINAHL, Scopus, EconBiz, GreenFile and ProQuest were searched from database inception to June 2026. Eligible studies reported measurement of carbon emissions related to clinical research activities. Data were charted and synthesised narratively.
resultsTwenty-five studies met the inclusion criteria, most published between 2019 and 2025 and primarily from Europe and the UK. Studies used a wide range of tools and resources, including life cycle assessment databases, online calculators, international standards, government emission factor datasets and healthcare-specific sustainability frameworks. A clear trade-off emerged between methodological rigour and accessibility: comprehensive life cycle assessment tools required expertise and licensing, while simpler calculators enabled rapid but less precise estimates. Carbon dioxide equivalent and global warming potential over a 100-year time horizon were the dominant reporting metrics, although variation in functional units limited comparability across studies.
conclusionsThe methodological landscape for measuring emissions in clinical research is fragmented and lacks standardisation. Development of consensus guidance and reporting standards is needed to support consistent measurement and reduction of research-related emissions.
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What OpenQuestion 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 OpenQuestion graph.