Evidence map›Paper›PMID 23403829›Full record

SynthesisBMJ (Clinical research ed.)2013

Comparative effect sizes in randomised trials from less developed and more developed countries: meta-epidemiological assessment.

Orestis A Panagiotou, Despina G Contopoulos-Ioannidis, John P A Ioannidis

Abstract readComparative StudyMeta-Analysis
PubMed Full text at PMC Publisher
In one paragraph

Synthesis in BMJ (Clinical research ed.), 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 40 papers, 15 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
40citing papers in PubMed, 15 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

40 citing papers in PubMed, 15 syntheses or guidelines pooled it.

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  3. Randomized controlled trials in patients with COVID-19: a systematic review and critical appraisal.International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases · 2022
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  7. Selective noradrenaline reuptake inhibitors for schizophrenia.The Cochrane database of systematic reviews · 2018
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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

3 authors.

Orestis A PanagiotouClinical Trials and Evidence-Based Medicine Unit, Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, University Campus, Ioannina, Greece.
Despina G Contopoulos-Ioannidis
John P A Ioannidis

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveTo compare treatment effects from randomised trials conducted in more developed versus less developed countries.

designMeta-epidemiological study. DATA SOURCES: Cochrane Database of Systematic Reviews (August 2012). DATA EXTRACTION: Meta-analyses with mortality outcomes including data from at least one randomised trial conducted in a less developed country and one in a more developed country. Relative risk estimates of more versus less developed countries were compared by calculating the relative relative risks for each topic and the summary relative relative risks across all topics. Similar analyses were performed for the primary binary outcome of each topic.

results139 meta-analyses with mortality outcomes were eligible. No nominally significant differences between more developed and less developed countries were found for 128 (92%) meta-analyses. However, differences were beyond chance in 11 (8%) cases, always showing more favourable treatment effects in trials from less developed countries. The summary relative relative risk was 1.12 (95% confidence interval 1.06 to 1.18; P<0.001; I(2)=0%), suggesting significantly more favourable mortality effects in trials from less developed countries. Results were similar for meta-analyses with nominally significant treatment effects for mortality (1.15), meta-analyses with recent trials (1.14), and when excluding trials from less developed countries that subsequently became more developed (1.12). For the primary binary outcomes (127 meta-analyses), 20 topics had differences in treatment effects beyond chance (more favourable in less developed countries in 15/20 cases).

conclusionsTrials from less developed countries in a few cases show significantly more favourable treatment effects than trials in more developed countries and, on average, treatment effects are more favourable in less developed countries. These discrepancies may reflect biases in reporting or study design as well as genuine differences in baseline risk or treatment implementation and should be considers when generalising evidence across different settings.

Indexed as

Developed CountriesDeveloping CountriesBiasHumansRandomized Controlled Trials as TopicRiskTreatment Outcome

Identifiers

PMID23403829
PMCPMC3570069

What OpenQuestion holds

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Registered trials

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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.