Evidence map›Paper›PMID 25334090›Full record

ArticleAnatolian journal of cardiology2015

The most critical question when reading a meta-analysis report: Is it comparing apples with apples or apples with oranges?

Pınar Kızılırmak, Oktay Özdemir, Zeki Öngen

Open access · hybridAbstract read
In one paragraph

Article in Anatolian journal of cardiology, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact, top 72% 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

2 citing papers in PubMed, 3 citations in OpenAlex.

  1. Article
  2. Article
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

3 authors at 3 institutions in 1 country.

Pınar KızılırmakDepartment of Medical Pharmacology, İstanbul University Faculty of Medicine, İstanbul-Turkey. pkizilirmak@gmail.com.
Oktay Özdemir
Zeki Öngen
Istanbul University · TRTeknoloji Arastirma ve Gelistirme Endustriyel Urunler Bilisim Teknolojileri San Tic · TRTürkisch-Deutsche Universität · TR

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveWhile the number of meta-analyses published has increased recently, most of them have problems in the design, analysis, and/or presentation. An example of meta-analyses with a study selection bias is a meta-analysis of over 160,000 patients in 20 clinical trials, published in Eur Heart J in 2012 by van Vark, which concluded that the significant effect of renin-angiotensin-aldosterone system (RAAS) inhibition on all-cause mortality was limited to the class of angiotensin-converting enzyme inhibitors (ACEIs), whereas no mortality reduction could be demonstrated with angiotensin receptor blockers (ARBs). Here, we aimed to discuss how to select studies for a meta-analysis and to present our results of a re-analysis of the van Vark data.

methodsThe data were re-analyzed in three steps: firstly, only ACEI/ARB-based studies (4 ACEI and 12 ARB studies) were included; secondly, placebo-controlled studies were excluded, and 10 studies left were analyzed; and thirdly, 2 studies that were retracted after the manuscript of van Vark had been published were excluded. The final analysis included 8 studies with ~65,000 patients (3 ACEI and 5 ARB studies).

resultsThe hazard ratios for all-cause mortality and cardiovascular mortality were 0.992 (95% CI 0.899-1.095; p=0.875) and 1.017 (0.932-1.110; p=0.703) for the ACEI versus control group and 1.007 (0.958-1.059; p=0.778) and 0.967 (0.911-1.025; p=0.258) for the ARB versus control group in the first step. The results were similar in the second and third steps.

conclusionThe studies to be included in meta-analyses, particularly comparing ACEIs and ARBs, should be chosen carefully.

Indexed as

Meta-Analysis as TopicAngiotensin-Converting Enzyme InhibitorsAngiotensin Receptor AntagonistsCardiovascular DiseasesHumansRandomized Controlled Trials as TopicSelection BiasAngiotensin-Converting Enzyme InhibitorsAngiotensin Receptor Antagonists

Identifiers

PMID25334090
PMCPMC5368477
OpenAlexW2326108382

What OpenQuestion holds

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LicenceCC BY-NC-SA
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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.