ArticleBMJ nutrition, prevention & health2021
How fragile are Mediterranean diet interventions? A research-on-research study of randomised controlled trials.
Article in BMJ nutrition, prevention & health, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers, 2 of them syntheses that pooled it.
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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.
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.
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Who cites it
14 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Fragility of cardiovascular outcome trials (CVOTs) examining nutrition interventions among patients with diabetes mellitus: a systematic review of randomized controlled trials.Hormones (Athens, Greece) · 2022Pooled it
- Pooled it
- Trial
- Understanding nutrition research for better patient care.BMJ nutrition, prevention & health · 2025Article
- Article
- Mediterranean Diet Interventions for Depressive Symptoms in Adults with Depressive Disorders: A Protocol for a Systematic Review and Meta-Analysis.International journal of environmental research and public health · 2022Article
- Diet and the microbiota - gut - brain-axis: a primer for clinical nutrition.Current opinion in clinical nutrition and metabolic care · 2022Review
- Basics of Sustainable Diets and Tools for Assessing Dietary Sustainability: A Primer for Researchers and Policy Actors.Healthcare (Basel, Switzerland) · 2022Review
- Paediatric surgical trials, their fragility index, and why to avoid using it to evaluate results.Pediatric surgery international · 2022Article
- The Niche of n-of-1 Trials in Precision Medicine for Weight Loss and Obesity Treatment: Back to the Future.Current nutrition reports · 2022Review
- Genetically-Guided Medical Nutrition Therapy in Type 2 Diabetes Mellitus and Pre-diabetes: A Series ofFrontiers in nutrition · 2022Article
- Level of Adherence to the Mediterranean Diet and Weight Status among Adolescent Female Gymnasts: A Cross-Sectional Study.Children (Basel, Switzerland) · 2021Article
- Article
- The fragility index may not be ideal for paediatric surgical conditions: the example of foetal endoscopic tracheal occlusion.Pediatric surgery international · 2021Article
Corrections and comments
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Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
introductionThe Mediterranean diet (MD) is a traditional regional dietary pattern and a healthy diet recommended for the primary and secondary prevention of various diseases and health conditions. Results from the higher level of primary evidence, namely randomised controlled trials (RCTs), are often used to produce dietary recommendations; however, the robustness of RCTs with MD interventions is unknown.
methodsA systematic search was conducted and all MD RCTs with dichotomous primary outcomes were extracted from PubMed. The fragility (FI) and the reverse fragility index (RFI) were calculated for the trials with significant and non-significant comparisons, respectively.
resultsOut of 27 RCTs of parallel design, the majority failed to present a significant primary outcome, exhibiting an FI equal to 0. The median FI of the significant comparisons was 5, ranging between 1 and 39. More than half of the comparisons had an FI <5, indicating that the addition of 1-4 events to the treatment arm eliminated the statistical significance. For the comparisons with an FI=0, the RFI ranged between 1 and 29 (Median RFI: 7). When the included RCTs were stratified according to masking, the use of a composite primary endpoint, sample size, outcome category, or dietary adherence assessment method, no differences were exhibited in the FI and RFI between groups, except for the RFI among different compliance assessment methods.
conclusionsIn essence, the present study shows that even in the top tiers of evidence hierarchy, research on the MD may lack robustness, setting concerns for the formulation of nutrition recommendations.
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