Evidence map›Paper›PMID 31651957›Full record

ArticleInternational journal of epidemiology2020

Impact of follow-up time and analytical approaches to account for reverse causality on the association between physical activity and health outcomes in UK Biobank.

Tessa Strain, Katrien Wijndaele, Stephen J Sharp, Paddy C Dempsey, Nick Wareham, Søren Brage

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Article in International journal of epidemiology, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 60 papers, 9 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
60citing papers in PubMed, 9 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

60 citing papers in PubMed, 9 syntheses or guidelines pooled it.

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  3. Effect of Excessive Daytime Sleepiness and Long Sleep Duration on All Cause Dementia: A Systematic Review and Meta-analysis.The journals of gerontology. Series A, Biological sciences and medical sciences · 2025
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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.

Tessa StrainMRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK.
Katrien WijndaeleMRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK.
Stephen J SharpMRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK.
Paddy C DempseyMRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK.
Nick WarehamMRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK.
Søren BrageMRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK.

Funding

Medical Research Council MC_PC_17228Medical Research Council MC_QA137853Medical Research Council MC_UU_00006/4Medical Research Council MC_UU_12015/1Medical Research Council MC_UU_12015/3
6 · The paper itself

Abstract

backgroundThe advent of very large cohort studies (n > 500 000) has given rise to prospective analyses of health outcomes being undertaken after short (<4 years) follow-up periods. However, these studies are potentially at risk of reverse causality bias. We investigated differences in the associations between self-reported physical activity and all-cause and cardiovascular disease (CVD) mortality, and incident CVD, using different follow-up time cut-offs and methods to account for reverse causality bias.

methodsData were from n = 452 933 UK Biobank participants, aged 38-73 years at baseline. Median available follow-up time was 7 years (for all-cause and CVD mortality) and 6.1 years (for incident CVD). We additionally analysed associations at 1-, 2- and 4-year cut-offs after baseline. We fit up to four models: (1) adjusting for prevalent CVD and cancer, (2) excluding prevalent disease, (3) and (4) Model 2 excluding incident cases in the first 12 and 24 months, respectively.

resultsThe strength of associations decreased as follow-up time cut-off increased. For all-cause mortality, Model 1 hazard ratios were 0.73 (0.69-0.78) after 1 year and 0.86 (0.84-0.87) after 7 years. Associations were weaker with increasing control for possible reverse causality. After 7-years follow-up, the hazard ratios were 0.86 (0.84-0.87) and 0.88 (0.86-0.90) for Models 1 and 4, respectively. Associations with CVD outcomes followed similar trends.

conclusionsAs analyses with longer follow-up times and increased control for reverse causality showed weaker associations, there are implications for the decision about when to analyse a cohort study with ongoing data collection, the interpretation of study results and their contribution to meta-analyses.

Indexed as

Life StyleMortalityAdultAgedCardiovascular DiseasesCausalityCohort StudiesExerciseFemaleFollow-Up StudiesHumansIncidenceMaleMiddle AgedNeoplasmsProspective Studiesbiasepidemiologic methodsExercisefollow-up studiesphysical activityprospective studies

Identifiers

PMID31651957
PMCPMC7124507

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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.