ArticleWorld journal of gastrointestinal oncology2020
Validity of studies suggesting preoperative chemotherapy for resectable thoracic esophageal cancer: A critical appraisal of randomized trials.
Article in World journal of gastrointestinal oncology, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.
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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.
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Who cites it
1 citing paper in PubMed, 1 citations in OpenAlex.
- Adjuvant chemotherapy in curatively resected rectal cancer: How valid are the data?World journal of gastrointestinal oncology · 2020Article
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Authors and funding
4 authors at 1 institution in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundIn 2015, Kidane published a Cochrane review and meta-analysis to summarise the impact of preoperative chemotherapy versus surgery alone on survival for resectable thoracic esophageal cancer. The authors concluded that preoperative chemotherapy improved overall survival (OS).
aimThe aim of this article was to assess the validity of the three most powerful studies included in the Cochrane review and the meta-analysis supporting the advantage of preoperative chemotherapy and to investigate the impact of an exclusion of these three studies on the result of the meta-analysis.
methodsOS was selected as the endpoint of interest. Among the ten included papers which analysed this endpoint, we identified the three publications with the highest weights influencing the final result. The validity of these papers was analysed using the CONSORT checklist for randomized controlled trials. We performed a new meta-analysis without the three studies to assess their impact on the general result of the original meta-analysis.
resultsThe three analysed studies revealed several inconsistencies. Inappropriate answers were found in up to one third of the items of the CONSORT checklist. Missing information about sample-size calculation and power, unclear or inadequate randomisation, and missing blinded set-up were the most common findings. When the three criticized studies were excluded in the meta-analysis, preoperative chemotherapy showed no benefit in OS.
conclusionThe three most powerful publications in the Cochrane review show substantial deficits. After the exclusion of these studies from the meta-analysis, preoperative chemotherapy does not seem to result in an advantage in survival. We suggest a more critical appraisal regarding the validity of single studies.
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