Evidence map›Paper›PMID 26202162›Full record

ArticleSystematic reviews2015

Handling trial participants with missing outcome data when conducting a meta-analysis: a systematic survey of proposed approaches.

Elie A Akl, Lara A Kahale, Thomas Agoritsas, Romina Brignardello-Petersen, Jason W Busse, Alonso Carrasco-Labra, Shanil Ebrahim, Bradley C Johnston, Ignacio Neumann, Ivan Sola and 5 more

Abstract read
In one paragraph

Article in Systematic reviews, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 30 papers, 14 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
30citing papers in PubMed, 14 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

30 citing papers in PubMed, 14 syntheses or guidelines pooled it.

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  9. Biofeedback for treatment of irritable bowel syndrome.The Cochrane database of systematic reviews · 2019
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  10. BMJ open · 2019
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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

15 authors.

Elie A AklDepartment of Internal Medicine, Clinical Epidemiology Unit, American University of Beirut Medical Center, P.O. Box: 11-0236, Riad-El-Solh, Beirut, 1107, 2020, Beirut, Lebanon. ea32@aub.edu.lb.
Lara A KahaleDepartment of Internal Medicine, Clinical Epidemiology Unit, American University of Beirut Medical Center, P.O. Box: 11-0236, Riad-El-Solh, Beirut, 1107, 2020, Beirut, Lebanon. lara.kahale@gmail.com.
Thomas AgoritsasDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. thomas.agoritsas@gmail.com.
Romina Brignardello-PetersenEvidence-Based Dentistry Unit, Universidad de Chile, Santiago, Chile. rominabp@gmail.com.
Jason W BusseDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. bussejw@mcmaster.ca.
Alonso Carrasco-LabraDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. alonsocarrascolabra@gmail.com.
Shanil EbrahimDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. shanil.ebrahim@utoronto.ca.
Bradley C JohnstonDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. bradley.johnston@sickkids.ca.
Ignacio NeumannDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. ignacio.neumann@gmail.com.
Ivan SolaIberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (CIBERESP-IIB Sant Pau), Barcelona, Spain. ISola@santpau.cat.
Xin SunDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. sunx26@gmail.com.
Per VandvikThe Norwegian Knowledge Centre for the Health Services, Oslo, Norway. per.vandvik@gmail.com.
Yuqing ZhangDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. madisonz1220@gmail.com.
Pablo Alonso-CoelloIberoamerican Cochrane Centre, Biomedical Research Institute Sant Pau (CIBERESP-IIB Sant Pau), Barcelona, Spain. PAlonso@santpau.cat.
Gordon GuyattDepartment of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada. guyatt@mcmaster.ca.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundWhen potentially associated with the likelihood of outcome, missing participant data represents a serious potential source of bias in randomized trials. Authors of systematic reviews frequently face this problem when conducting meta-analyses. The objective of this study is to conduct a systematic survey of the relevant literature to identify proposed approaches for how systematic review authors should handle missing participant data when conducting a meta-analysis.

methodsWe searched MEDLINE and the Cochrane Methodology register from inception to August 2014. We included papers that devoted at least two paragraphs to discuss a relevant approach for missing data. Five pairs of reviewers, working independently and in duplicate, selected relevant papers. One reviewer abstracted data from included papers and a second reviewer verified them. We summarized the results narratively.

resultsOf 9,138 identified citations, we included 11 eligible papers. Four proposed general approaches for handling dichotomous outcomes, and all recommended a complete case analysis as the primary analysis and additional sensitivity analyses using the following imputation methods: based on reasons for missingness (n = 3), relative to risk among followed up (n = 3), best-case scenario (n = 2), and worst-case scenario (n = 3). Three of these approaches suggested taking uncertainty into account. Two papers proposed general approaches for handling continuous outcomes, and both proposed a complete case analysis as the reference analysis and the following imputation methods as sensitivity analyses: based on reasons for missingness (n = 2), based on the mean observed in the same trial or other trials (n = 1), and based on informative missingness differences in means (n = 1). The remaining eligible papers did not propose general approaches but addressed specific statistical issues.

conclusionsAll proposed approaches for handling missing participant data recommend conducting a complete case analysis for the primary analysis and some form of sensitivity analysis to evaluate robustness of results. Although these approaches require further testing, they may guide review authors in addressing missing participant data.

Indexed as

BiasData AccuracyMeta-Analysis as TopicPatient DropoutsHumansResearch DesignSurveys and Questionnaires

Identifiers

PMID26202162
PMCPMC4511978

What OpenQuestion holds

Textmetadata
LicenceCC BY
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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.