Duplicated network meta-analysis in advanced prostate cancer: a case study and recommendations for change
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A Bioluminescent and Fluorescent Orthotopic Syngeneic Murine Model of Androgen-dependent and Castration-resistant Prostate Cancer
Published on: March 6, 2018
David J Fisher1, Sarah Burdett2, Claire Vale2
1MRC Clinical Trials Unit at UCL, Institute of Clinical Trials and Methodology, Unversity College London, 90 High Holborn, London, WC1V 6LJ, UK. d.fisher@ucl.ac.uk.
Background:
Research overlap and duplication is a recognised problem in the context of both pairwise and network systematic reviews and meta-analyses. As a case study, we carried out a scoping review to identify and examine duplicated network meta-analyses (NMAs) in a specific disease setting where several novel therapies have recently emerged: hormone-sensitive metastatic prostate cancer (mHSPC).
Methods:
MEDLINE and EMBASE were systematically searched, in January 2020, for indirect or mixed treatment comparisons or network meta-analyses of the systemic treatments docetaxel and abiraterone acetate in the mHSPC setting, with a time-to-event outcome reported on the hazard-ratio scale. Eligibility decisions were made, and data extraction performed, by two independent reviewers.
Results:
A total of 13 eligible reviews were identified, analysing between 3 and 8 randomised comparisons, and comprising between 1773 and 7844 individual patients. Although the included trials and treatments showed a high degree of overlap, we observed considerable variation between identified reviews in terms of review aims, eligibility criteria and included data, statistical methodology, reporting and inference. Furthermore, crucial methodological details and specific source data were often unclear.
Conclusions And Recommendations:
Variation across duplicated NMAs, together with reporting inadequacies, may compromise identification of best-performing treatments. Particularly in fast-moving fields, review authors should be aware of all relevant studies, and of other reviews with potential for overlap or duplication. We recommend that review protocols be published in advance, with greater clarity regarding the specific aims or scope of the project, and that reports include information on how the work builds upon existing knowledge. Source data and results should be clearly and completely presented to allow unbiased interpretation.
Insights
Duplicated network meta-analyses (NMAs) in hormone-sensitive metastatic prostate cancer show significant variation in methods and reporting. This overlap may hinder identifying optimal treatments, emphasizing the need for clear protocols and complete data presentation.
Area of Science:
- Medical research methodology
- Oncology
- Evidence synthesis
Background:
- Research overlap and duplication are recognized issues in systematic reviews and meta-analyses.
- Network meta-analyses (NMAs) are increasingly used for comparing multiple treatments.
- Hormone-sensitive metastatic prostate cancer (mHSPC) is a rapidly evolving field with emerging novel therapies.
Purpose of the Study:
- To conduct a scoping review identifying and examining duplicated NMAs in mHSPC.
- To assess the extent of overlap and variation in existing NMAs for mHSPC treatments.
- To highlight potential implications of duplicated NMAs on treatment selection and evidence interpretation.
Main Methods:
- Systematic literature search of MEDLINE and EMBASE databases in January 2020.
- Inclusion of NMAs comparing systemic treatments (docetaxel, abiraterone acetate) for mHSPC with time-to-event outcomes.
- Data extraction and eligibility decisions performed by two independent reviewers.
Main Results:
- Identified 13 eligible NMAs with substantial overlap in included trials and treatments.
- Observed considerable variation in review aims, eligibility criteria, data, statistical methods, reporting, and inference.
- Noted frequent lack of clarity regarding crucial methodological details and source data.
Conclusions:
- Variation and reporting inadequacies in duplicated NMAs can compromise the identification of best-performing treatments.
- Review authors must be aware of existing studies and potential for duplication, especially in fast-moving fields.
- Recommendations include publishing review protocols in advance, clarifying project scope, and presenting source data clearly for unbiased interpretation.
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