Evidence map›Paper›PMID 41737145›Full record

ArticleBMJ medicine2026

Identifying and avoiding design related biases in observational studies using the target trial framework.

Harrison J Hansford, Nazrul Islam, Hopin Lee, Barbra A Dickerman, Aidan G Cashin

Abstract read
In one paragraph

Article in BMJ medicine, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–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

0 citing papers in PubMed.

No citing paper in PubMed yet.

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

5 authors.

Harrison J HansfordSchool of Health Sciences, Faculty of Medicine and Health, UNSW Sydney, Sydney, NSW, Australia.ORCID https://orcid.org/0000-0002-5942-8509
Nazrul IslamPrimary Care Research Centre, Faculty of Medicine, University of Southampton, Southampton, UK.ORCID https://orcid.org/0000-0003-3982-4325
Hopin LeeUniversity of Exeter Medical School, Exeter, UK.
Barbra A DickermanCAUSALab, Department of Epidemiology, Harvard T H Chan School of Public Health, Boston, MA, USA.
Aidan G CashinCentre for Pain IMPACT, Neuroscience Research Australia, Randwick, NSW, Australia.ORCID https://orcid.org/0000-0003-4190-7912

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Observational studies are necessary to provide evidence to inform decision making in the absence of a relevant randomised trial. Although commonly criticised for potential problems due to confounding bias, design related biases in observational studies are often overlooked yet highly prevalent. Design related biases occur because of decisions made by researchers during analyses of observational data. Common design related biases include bias related to selection and treatment misclassification, resulting from misalignment of eligibility ascertainment, treatment strategy assignment, and start of follow-up. Conceptualising the analysis of observational data to estimate the causal effects of interventions as an attempt to explicitly emulate a target trial can help avoid design related biases, so that investigators can instead focus on data related biases (eg, confounding, measurement error) not directly addressed by the framework. Target trial emulation may also help readers appraise an observational study when transparently reported. This article aims to help readers of observational studies identify and avoid design related biases to support the use of observational evidence to inform clinical and policy decision making.

Indexed as

EpidemiologyMedicinePublic healthResearch design

Identifiers

PMID41737145
PMCPMC12927355

What OpenQuestion holds

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Registered trials

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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.