Evidence map›Paper›PMID 38448992›Full record

ArticleBMC medicine2024

Influence of lack of blinding on the estimation of medication-related harms: a retrospective cohort study of randomized controlled trials.

Chang Xu, Fengying Zhang, Suhail A R Doi, Luis Furuya-Kanamori, Lifeng Lin, Haitao Chu, Xi Yang, Sheyu Li, Liliane Zorzela, Su Golder and 2 more

Abstract read
In one paragraph

Article in BMC medicine, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
6citing 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.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

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

  1. Pooled it
  2. Trial
  3. Review
  4. Article
  5. Article
  6. Article
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

12 authors.

Chang XuProof of Concept Center, Eastern Hepatobiliary Surgery Hospital, Third Affiliated Hospital, Second Military Medical University, Naval Medical University, Shanghai, China. xuchang2016@runbox.com.ORCID 0000-0002-2627-1250
Fengying ZhangChinese Evidence-Based Medicine Center, West China Hospital, Sichuan University, Chengdu, China.
Suhail A R DoiDepartment of Population Medicine, College of Medicine, QU Health, Qatar University, Doha, Qatar.
Luis Furuya-KanamoriUQ Center for Clinical Research, The University of Queensland, Herston, Australia.
Lifeng LinDepartment of Epidemiology and Biostatistics, University of Arizona, Tucson, AZ, USA.
Haitao ChuStatistical Research and Innovation, Global Biometrics and Data Management, Pfizer Inc, New York, NY, USA.
Xi YangProof of Concept Center, Eastern Hepatobiliary Surgery Hospital, Third Affiliated Hospital, Second Military Medical University, Naval Medical University, Shanghai, China.
Sheyu LiDepartment of Endocrinology and Metabolism, MAGIC China Centre, West China Hospital, Sichuan University, Chengdu, China.
Liliane ZorzelaDepartment of Pediatrics, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, AB, Canada.
Su GolderDepartment of Health Sciences, University of York, York, UK.
Yoon LokeNorwich Medical School, University of East Anglia, Norwich, UK.
Sunita VohraDepartments of Pediatrics & Psychiatry, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, AB, Canada.

Funding

National Natural Science Foundation of China 72204003Qatar National Research Fund NPRP-BSRA01-0406-210030
6 · The paper itself

Abstract

backgroundEmpirical evidence suggests that lack of blinding may be associated with biased estimates of treatment benefit in randomized controlled trials, but the influence on medication-related harms is not well-recognized. We aimed to investigate the association between blinding and clinical trial estimates of medication-related harms.

methodsWe searched PubMed from January 1, 2015, till January 1, 2020, for systematic reviews with meta-analyses of medication-related harms. Eligible meta-analyses must have contained trials both with and without blinding. Potential covariates that may confound effect estimates were addressed by restricting trials within the comparison or by hierarchical analysis of harmonized groups of meta-analyses (therefore harmonizing drug type, control, dosage, and registration status) across eligible meta-analyses. The weighted hierarchical linear regression was then used to estimate the differences in harm estimates (odds ratio, OR) between trials that lacked blinding and those that were blinded. The results were reported as the ratio of OR (ROR) with its 95% confidence interval (CI).

resultsWe identified 629 meta-analyses of harms with 10,069 trials. We estimated a weighted average ROR of 0.68 (95% CI: 0.53 to 0.88, P < 0.01) among 82 trials in 20 meta-analyses where blinding of participants was lacking. With regard to lack of blinding of healthcare providers or outcomes assessors, the RORs were 0.68 (95% CI: 0.53 to 0.87, P < 0.01 from 81 trials in 22 meta-analyses) and 1.00 (95% CI: 0.94 to 1.07, P = 0.94 from 858 trials among 155 meta-analyses) respectively. Sensitivity analyses indicate that these findings are applicable to both objective and subjective outcomes.

conclusionsLack of blinding of participants and health care providers in randomized controlled trials may underestimate medication-related harms. Adequate blinding in randomized trials, when feasible, may help safeguard against potential bias in estimating the effects of harms.

Indexed as

Health PersonnelHumansLinear ModelsRandomized Controlled Trials as TopicRetrospective StudiesSystematic Reviews as TopicAdverse effectsBlindingHarmsRandomized controlled trials

Identifiers

PMID38448992
PMCPMC10919027

What Socratic holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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.