IDEAS home Printed from https://ideas.repec.org/a/plo/pone00/0115934.html
   My bibliography  Save this article

A Case Study of Discordant Overlapping Meta-Analyses: Vitamin D Supplements and Fracture

Author

Listed:
  • Mark J Bolland
  • Andrew Grey

Abstract

Background: Overlapping meta-analyses on the same topic are now very common, and discordant results often occur. To explore why discordant results arise, we examined a common topic for overlapping meta-analyses- vitamin D supplements and fracture. Methods and Findings: We identified 24 meta-analyses of vitamin D (with or without calcium) and fracture in a PubMed search in October 2013, and analysed a sample of 7 meta-analyses in the highest ranking general medicine journals. We used the AMSTAR tool to assess the quality of the meta-analyses, and compared their methodologies, analytic techniques and results. Applying the AMSTAR tool suggested the meta-analyses were generally of high quality. Despite this, there were important differences in trial selection, data extraction, and analytical methods that were only apparent after detailed assessment. 25 trials were included in at least one meta-analysis. Four meta-analyses included all eligible trials according to the stated inclusion and exclusion criteria, but the other 3 meta-analyses “missed” between 3 and 8 trials, and 2 meta-analyses included apparently ineligible trials. The relative risks used for individual trials differed between meta-analyses for total fracture in 10 of 15 trials, and for hip fracture in 6 of 12 trials, because of different outcome definitions and analytic approaches. The majority of differences (11/16) led to more favourable estimates of vitamin D efficacy compared to estimates derived from unadjusted intention-to-treat analyses using all randomised participants. The conclusions of the meta-analyses were discordant, ranging from strong statements that vitamin D prevents fractures to equally strong statements that vitamin D without calcium does not prevent fractures. Conclusions: Substantial differences in trial selection, outcome definition and analytic methods between overlapping meta-analyses led to discordant estimates of the efficacy of vitamin D for fracture prevention. Strategies for conducting and reporting overlapping meta-analyses are required, to improve their accuracy and transparency.

Suggested Citation

  • Mark J Bolland & Andrew Grey, 2014. "A Case Study of Discordant Overlapping Meta-Analyses: Vitamin D Supplements and Fracture," PLOS ONE, Public Library of Science, vol. 9(12), pages 1-20, December.
  • Handle: RePEc:plo:pone00:0115934
    DOI: 10.1371/journal.pone.0115934
    as

    Download full text from publisher

    File URL: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0115934
    Download Restriction: no

    File URL: https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0115934&type=printable
    Download Restriction: no

    File URL: https://libkey.io/10.1371/journal.pone.0115934?utm_source=ideas
    LibKey link: if access is restricted and if your library uses this service, LibKey will redirect you to where you can use your library subscription to access this item
    ---><---

    References listed on IDEAS

    as
    1. Hilda Bastian & Paul Glasziou & Iain Chalmers, 2010. "Seventy-Five Trials and Eleven Systematic Reviews a Day: How Will We Ever Keep Up?," PLOS Medicine, Public Library of Science, vol. 7(9), pages 1-6, September.
    Full references (including those not matched with items on IDEAS)

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Dreesens, Dunja & Kremer, Leontien & Burgers, Jako & van der Weijden, Trudy, 2020. "Lost in definitions: Reducing duplication and clarifying definitions of knowledge and decision support tools. A RAND-modified Delphi consensus study," Health Policy, Elsevier, vol. 124(5), pages 531-539.
    2. Blake M. Louscher & Veerasathpurush Allareddy & Satheesh Elangovan, 2019. "Predictors of Citations of Systematic Reviews in Oral Implantology: A Cross-Sectional Bibliometric Analysis," SAGE Open, , vol. 9(1), pages 21582440198, March.
    3. Hansen, Henrik & Trifkovic, Neda, 2013. "Systematic Reviews: Questions, Methods and Usage," MPRA Paper 47993, University Library of Munich, Germany.
    4. Shi, Xuanyu & Du, Jian, 2022. "Distinguishing transformative from incremental clinical evidence: A classifier of clinical research using textual features from abstracts and citing sentences," Journal of Informetrics, Elsevier, vol. 16(2).
    5. Jason Portenoy & Jevin D. West, 2020. "Constructing and evaluating automated literature review systems," Scientometrics, Springer;Akadémiai Kiadó, vol. 125(3), pages 3233-3251, December.
    6. Dreesens, Dunja & Kremer, Leontien & van der Weijden, Trudy, 2019. "The Dutch chaos case: A scoping review of knowledge and decision support tools available to clinicians in the Netherlands," Health Policy, Elsevier, vol. 123(12), pages 1288-1297.
    7. Joerg J Meerpohl & Florian Herrle & Gerd Antes & Erik von Elm, 2012. "Scientific Value of Systematic Reviews: Survey of Editors of Core Clinical Journals," PLOS ONE, Public Library of Science, vol. 7(5), pages 1-5, May.
    8. Lucy Turner & James Galipeau & Chantelle Garritty & Eric Manheimer & L Susan Wieland & Fatemeh Yazdi & David Moher, 2013. "An Evaluation of Epidemiological and Reporting Characteristics of Complementary and Alternative Medicine (CAM) Systematic Reviews (SRs)," PLOS ONE, Public Library of Science, vol. 8(1), pages 1-11, January.
    9. K. M. Saif‐Ur‐Rahman & Md. Hasan & Shahed Hossain & Iqbal Anwar & Yoshihisa Hirakawa & Hiroshi Yatsuya, 2022. "Prioritization and sequential exclusion of articles in systematic reviews," Campbell Systematic Reviews, John Wiley & Sons, vol. 18(2), June.
    10. Monique Heijmans & Rune Poortvliet & Marieke Van der Gaag & Ana I. González-González & Jessica Beltran Puerta & Carlos Canelo-Aybar & Claudia Valli & Marta Ballester & Claudio Rocha & Montserrat León , 2022. "Using a Taxonomy to Systematically Identify and Describe Self-Management Interventions Components in Randomized Trials for COPD," IJERPH, MDPI, vol. 19(19), pages 1-24, October.
    11. Tanja Burgard & Holger Steinmetz, 2023. "Evidence in management science related to psychology: benefits, tools, and an example of a community-augmented meta-analysis," Management Review Quarterly, Springer, vol. 73(3), pages 1135-1150, September.
    12. Laura Sheble, 2017. "Macro‐level diffusion of a methodological knowledge innovation: Research synthesis methods, 1972–2011," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 68(12), pages 2693-2708, December.
    13. Md Mahbub Hossain & Abida Sultana & Samia Tasnim & Qiping Fan & Ping Ma & E Lisako J McKyer & Neetu Purohit, 2020. "Prevalence of mental disorders among people who are homeless: An umbrella review," International Journal of Social Psychiatry, , vol. 66(6), pages 528-541, September.
    14. Costa, King & Ntsobi, Mfanelo Patrick, 2023. "A Systematic Review of the Potential for Promotion of Southern Epistemologies in Educational Research: Ubuntu Philosophy as a Research Paradigm, a Conceptual Model," AfricArxiv qshp8, Center for Open Science.
    15. Means, Stephanie N. & Magura, Stephen & Burkhardt, Jason T. & Schröter, Daniela C. & Coryn, Chris L.S., 2015. "Comparing rating paradigms for evidence-based program registers in behavioral health: Evidentiary criteria and implications for assessing programs," Evaluation and Program Planning, Elsevier, vol. 48(C), pages 100-116.
    16. Porjai Pattanittum & Malinee Laopaiboon & David Moher & Pisake Lumbiganon & Chetta Ngamjarus, 2012. "A Comparison of Statistical Methods for Identifying Out-of-Date Systematic Reviews," PLOS ONE, Public Library of Science, vol. 7(11), pages 1-6, November.
    17. Gillian L Currie & Helena N Angel-Scott & Lesley Colvin & Fala Cramond & Kaitlyn Hair & Laila Khandoker & Jing Liao & Malcolm Macleod & Sarah K McCann & Rosie Morland & Nicki Sherratt & Robert Stewart, 2019. "Animal models of chemotherapy-induced peripheral neuropathy: A machine-assisted systematic review and meta-analysis," PLOS Biology, Public Library of Science, vol. 17(5), pages 1-34, May.
    18. Melanie Lum & Luke Wolfenden & Jannah Jones & Alice Grady & Hayley Christian & Kathryn Reilly & Sze Lin Yoong, 2022. "Interventions to Improve Child Physical Activity in the Early Childhood Education and Care Setting: An Umbrella Review," IJERPH, MDPI, vol. 19(4), pages 1-22, February.
    19. Tiago S. Jesus & Helen Hoenig & Michel D. Landry, 2020. "Development of the Rehabilitation Health Policy, Systems, and Services Research Field: Quantitative Analyses of Publications over Time (1990–2017) and across Country Type," IJERPH, MDPI, vol. 17(3), pages 1-17, February.
    20. Furukawa, Chishio, 2019. "Publication Bias under Aggregation Frictions: Theory, Evidence, and a New Correction Method," EconStor Preprints 194798, ZBW - Leibniz Information Centre for Economics.

    More about this item

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:plo:pone00:0115934. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: plosone (email available below). General contact details of provider: https://journals.plos.org/plosone/ .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.