Evidence map›Paper›PMID 28398582›Full record

ArticleInternational journal of epidemiology2017

How to compare instrumental variable and conventional regression analyses using negative controls and bias plots.

Neil M Davies, Kyla H Thomas, Amy E Taylor, Gemma M J Taylor, Richard M Martin, Marcus R Munafò, Frank Windmeijer

Open access · hybridAbstract read
In one paragraph

Article in International journal of epidemiology, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 29 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
29citing papers in PubMed, 2 pooled it
3.6field-weighted citation impact, top 6% 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

29 citing papers in PubMed, 2 syntheses or guidelines pooled it, 53 citations in OpenAlex.

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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

7 authors at 3 institutions in 1 country.

Neil M DaviesMedical Research Council Integrative Epidemiology Unit.
Kyla H ThomasMedical Research Council Integrative Epidemiology Unit.
Amy E TaylorMedical Research Council Integrative Epidemiology Unit.
Gemma M J TaylorMedical Research Council Integrative Epidemiology Unit.
Richard M MartinMedical Research Council Integrative Epidemiology Unit.
Marcus R MunafòMedical Research Council Integrative Epidemiology Unit.
Frank WindmeijerMedical Research Council Integrative Epidemiology Unit.
Medical Research Council · GBMRC Integrative Epidemiology UnitUK Centre for Tobacco & Alcohol Studies · GB

Funding

British Heart FoundationCancer Research UK 19169Cancer Research UK 21330Cancer Research UK C18281/A19169Department of Health 14/49/94Department of Health HTA/15/58/18Medical Research Council MC_UU_12013/6Medical Research Council MC_UU_12013/9Medical Research Council MR/N01006X/1
6 · The paper itself

Abstract

There is increasing interest in the use of instrumental variable analysis to overcome unmeasured confounding in observational pharmacoepidemiological studies. This is partly because instrumental variable analyses are potentially less biased than conventional regression analyses. However, instrumental variable analyses are less precise, and regulators and clinicians find it difficult to interpret conflicting evidence from instrumental variable compared with conventional regression analyses. In this paper, we describe three techniques to assess which approach (instrumental variable versus conventional regression analyses) is least biased. These techniques are negative control outcomes, negative control populations and tests of covariate balance. We illustrate these methods using an analysis of the effects of smoking cessation therapies (varenicline) prescribed in primary care.

Indexed as

Case-Control StudiesCausalityConfounding Factors, EpidemiologicRegression AnalysisBiasData Interpretation, StatisticalHumansOutcome Assessment, Health CarePharmacoepidemiologycausal inferenceInstrumental variablesnegative controlspharmacoepidemiology

Identifiers

PMID28398582
PMCPMC5837536
OpenAlexW2587176846

What OpenQuestion 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 OpenQuestion graph.