Response to Igor Eckert: Sometimes, the absence of evidence is evidence of its absence

  • Alfred Adiamah
    Affiliations
    Nottingham Digestive Diseases Centre and National Institute for Health Research Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
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  • Simon P. Allison
    Affiliations
    Nottingham Digestive Diseases Centre and National Institute for Health Research Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
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  • Dileep N. Lobo
    Correspondence
    Corresponding author. Nottingham Digestive Diseases Centre, National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK. Fax: +44 115 8231160.
    Affiliations
    Nottingham Digestive Diseases Centre and National Institute for Health Research Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
    MRC Versus Arthritis Centre for Musculoskeletal Ageing Research, School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, UK
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Published:November 25, 2021DOI:https://doi.org/10.1016/j.clnu.2021.11.022
      “The absence of evidence is not evidence of absence”, is an aphorism attributed to Carl Sagan [
      • Sagan C.
      The demon-haunted world: science as a candle in the dark.
      ], which is invoked when claims of the existence of God are encountered. Nonetheless, it is a succinct and elegant statement, which in this instance is simultaneously beautiful and wrong. At first glance, the lack of evidence is not evidence of absence, would suggest that for every treatment: medical, nutritional, or alternative therapy unless science has exhausted every mechanistic process available we cannot state it does not work even after randomised, double-blind studies, or as is the case here, multiple systematic reviews, none of which have found survival benefit.

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      Linked Article

      • Inaccurate conclusions due to absence of evidence fallacy on Adiamah et al
        Clinical Nutrition
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          In a long-term survival analysis [1], Adiamah and colleagues conclude that early postoperative enteral feeding with arginine-enriched immunomodulating nutrition (IMN) confers no additional benefit compared with a control formula. This conclusion of absence of effect assumes the study provides evidence that the treatment confers no benefit. In this letter, I argue that the correct interpretation of these results would lead to different conclusions and potential real-life implications.
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