Evidence map›Paper›PMID 40101228›Full record

Trial reportJMIR public health and surveillance2025

Alternative Presentations of Overall and Statistical Uncertainty for Adults' Understanding of the Results of a Randomized Trial of a Public Health Intervention: Parallel Web-Based Randomized Trials.

Christine Holst, Steven Woloshin, Andrew D Oxman, Christopher Rose, Sarah Rosenbaum, Heather Menzies Munthe-Kaas

Registry-linked trialAbstract readRandomized Controlled Trial
In one paragraph

Trial report in JMIR public health and surveillance, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT05642754 (Communicating Uncertainty About the Effects of Wearing Glasses to Reduce the Chance of Getting COVID), which is not on this map. Cited by 2 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed, 1 pooled it
–field-weighted citation impact
1 · What the graph read from it

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.

2 · The registry

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.

NCT05642754 nacompletednot on this map

Communicating Uncertainty About the Effects of Wearing Glasses to Reduce the Chance of Getting COVID (Corona Virus Disease): Protocol for a Randomized Trial

TypeinterventionalSponsorTrustees of Dartmouth CollegeRan2022 to 2023Enrolled960ConditionsCOVID-19ArmsOverall uncertainty language
3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 1 synthesis or guideline pooled it.

  1. Pooled it
  2. Navigating the Prescription Drug Information System.Clinical pharmacology and therapeutics · 2026
    Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Christine HolstCentre for Epidemic Interventions Research, Norwegian Institute of Public Health, Oslo, Norway.ORCID 0000-0002-6084-0701
Steven WoloshinLisa Schwartz Foundation for Truth in Medicine, Norwich, VT, United States.ORCID 0000-0003-2311-1005
Andrew D OxmanCentre for Epidemic Interventions Research, Norwegian Institute of Public Health, Oslo, Norway.ORCID 0000-0002-5608-5061
Christopher RoseCentre for Epidemic Interventions Research, Norwegian Institute of Public Health, Oslo, Norway.ORCID 0000-0001-6457-8168
Sarah RosenbaumCentre for Epidemic Interventions Research, Norwegian Institute of Public Health, Oslo, Norway.ORCID 0000-0001-8334-7664
Heather Menzies Munthe-KaasCentre for Epidemic Interventions Research, Norwegian Institute of Public Health, Oslo, Norway.ORCID 0000-0002-6051-9010

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundWell-designed public health messages can help people make informed choices, while poorly designed messages or persuasive messages can confuse, lead to poorly informed decisions, and diminish trust in health authorities and research. Communicating uncertainties to the public about the results of health research is challenging, necessitating research on effective ways to disseminate this important aspect of randomized trials.

objectiveThis study aimed to evaluate people's understanding of overall and statistical uncertainty when presented with alternative ways of expressing randomized trial results.

methodsTwo parallel, web-based, individually randomized trials (3×2 factorial designs) were conducted in the United States and Norway. Participants were randomized to 1 of 6 versions of a text (summary) communicating results from a study examining the effects of wearing glasses to prevent COVID-19 infection. The summaries varied in how overall uncertainty ("Grading of Recommendations Assessment, Development and Evaluation [GRADE] language," "plain language," or "no explicit language") and statistical uncertainty (whether a margin of error was shown or not) were presented. Participants completed a web-based questionnaire exploring 4 coprimary outcomes: 3 to measure understanding of overall uncertainty (benefits, harms, and sufficiency of evidence), and one to measure statistical uncertainty. Participants were adults who do not wear glasses recruited from web-based research panels in the United States and Norway. Results of the trials were analyzed separately and combined in a meta-analysis.

resultsIn the US and Norwegian trials, 730 and 497 individuals were randomized, respectively; data for 543 (74.4%) and 452 (90.9%) were analyzed. More participants had a correct understanding of uncertainty when presented with plain language (United States: 37/99, 37% and Norway: 40/76, 53%) than no explicit language (United States: 18/86, 21% and Norway: 34/80, 42%). Similar positive effect was seen for the GRADE language in the United States (26/79, 33%) but not in Norway (30/71, 42%). There were only small differences between groups for understanding the uncertainty of harms. Plain language improved correct understanding of evidence sufficiency (odds ratio 2.05, 95% CI 1.17-3.57), compared to no explicit language. The effect of GRADE language was inconclusive (odds ratio 1.34, 95% CI 0.79-2.28). The understanding of statistical uncertainty was improved when the participants were shown the margin of error compared to not being shown: Norway: 16/75, 21% to 24/71, 34% vs 1/71, 1% to 2/76, 3% and the United States: 21/101, 21% to 32/90, 36% vs 0/86, 0% to 3/79, 4%).

conclusionsPlain language, but not GRADE language, was better than no explicit language in helping people understand overall uncertainty of benefits and harms. Reporting margin of error improved understanding of statistical uncertainty around the effect of wearing glasses, but only for a minority of participants.

trial registrationClinicalTrials.gov NCT05642754; https://tinyurl.com/4mhjsm7s.

Indexed as

ComprehensionPublic HealthAdultCOVID-19FemaleHumansInternetMaleMiddle AgedNorwayRandomized Controlled Trials as TopicSurveys and QuestionnairesUncertaintyUnited StatesYoung AdultcommunicationGRADE languageGrading of Recommendations Assessment, Development, and Evaluation languageoverall uncertaintyrandomized trialstatistical uncertainty

Identifiers

PMID40101228
PMCPMC11962331

What OpenQuestion holds

Textmetadata
LicenceCC BY
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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.