Evidence map›Paper›PMID 38191258›Full record

ArticleBMJ open2024

Risk factors for SARS-CoV-2 infection: a test-negative case-control study with additional population controls in Norway.

Marjut Sarjomaa, Chi Zhang, Yngvar Tveten, Hege Kersten, Harald Reiso, Randi Eikeland, Johny Kongerud, Kristine Karlsrud Berg, Carina Thilesen, Svein Arne Nordbø and 4 more

Open access · goldAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in BMJ open, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
1.2field-weighted citation impact, top 25% of its field
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

3 citing papers in PubMed, 3 citations in OpenAlex.

  1. Article
  2. Observational
  3. 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

14 authors at 9 institutions in 7 countries.

Marjut SarjomaaInfection Control, Telemark Hospital, Skien, Norway sarm@sthf.no.ORCID 0000-0002-0559-7251
Chi ZhangDepartment of Biostatistics, University of Oslo, Oslo, Norway.
Yngvar TvetenDepartment of Clinical Microbiology, Telemark Hospital, Skien, Norway.
Hege KerstenDepartment of Research, Telemark Hospital, Skien, Norway.
Harald ReisoThe Norwegian Advisory Unit on Tick-borne Diseases, Sørlandet sykehus HF Arendal, Arendal, Norway.
Randi EikelandNeurology, Sørlandet sykehus HF Arendal, Arendal, Norway.
Johny KongerudClinical Medicine, University of Oslo, Oslo, Norway.
Kristine Karlsrud BergDepartment of Medical Microbiology, Sørlandet Sykehus HF, Kristiansand, Norway.
Carina ThilesenUnilabs Laboratory Medicine, Skien, Norway.
Svein Arne NordbøDepartment of Medical Microbiology, St Olavs Hospital Trondheim University Hospital, Trondheim, Norway.
Ingeborg S AabergeNorwegian Institute of Public Health, Oslo, Norway.
Jan VandenbrouckeClinical Epidemiology, University of Leiden, Leiden, The Netherlands.
Neil PearceMedical Statistics, London School of Hygiene and Tropical Medicine, London, UK.ORCID 0000-0002-9938-7852
Anne Kristin Moeller FellOccupational and environmental Medicine, Sykehuset Telemark HF, Skien, Norway.ORCID 0000-0002-3345-774X
University of Oslo · NONorwegian Institute of Public Health · NOSørlandet Hospital Arendal · NOTelemark Hospital · NOLeiden University · NLLondon School of Hygiene & Tropical Medicine · GBNorwegian University of Science and Technology · NOUnilabs (Norway) · NOUniversity of Agder · NO

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectivesThis study aims to assess risk factors for SARS-CoV-2 infection by combined design; first comparing positive cases to negative controls as determined by PCR testing and then comparing these two groups to an additional prepandemic population control group. DESIGN AND

settingTest-negative design (TND), multicentre case-control study with additional population controls in South-Eastern Norway.

participantsAdults who underwent SARS-CoV-2 PCR testing between February and December 2020. PCR-positive cases, PCR-negative controls and additional age-matched population controls. PRIMARY OUTCOME MEASURES: The associations between various risk factors based on self- reported questionnaire and SARS-CoV-2 infection comparing PCR-positive cases and PCR-negative controls. Using subgroup analysis, the risk factors for both PCR-positive and PCR-negative participants were compared with a population control group.

resultsIn total, 400 PCR-positive cases, 719 PCR-negative controls and 14 509 population controls were included. Male sex was associated with the risk of SARS-CoV-2 infection only in the TND study (OR 1.9, 95% CI 1.4 to 2.6), but not when PCR-positive cases were compared with population controls (OR 1.2, 95% CI 0.9. to 1.5). Some factors were positively (asthma, wood heating) or negatively (hypertension) associated with SARS-CoV-2 infection when PCR-positive cases were compared with population controls, but lacked convincing association in the TND study. Smoking was negatively associated with the risk of SARS-CoV-2 infection in both analyses (OR 0.5, 95% CI 0.3 to 0.8 and OR 0.6, 95% CI 0.4 to 0.8).

conclusionsMale sex was a possible risk factor for SARS-CoV-2 infection only in the TND study, whereas smoking was negatively associated with SARS-CoV-2 infection in both the TND study and when using population controls. Several factors were associated with SARS-CoV-2 infection when PCR-positive cases were compared with population controls, but not in the TND study, highlighting the strength of combining case-control study designs during the pandemic.

Indexed as

COVID-19AdultCase-Control StudiesHumansMaleNorwayPopulation ControlRisk FactorsSARS-CoV-2case-control studiesCOVID-19risk factorsSARS-CoV-2 infection

Identifiers

PMID38191258
PMCPMC10806780
OpenAlexW4390699906

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC
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 OpenQuestion graph.