ArticleEuropean journal of clinical investigation2016
Observational research rigour alone does not justify causal inference.
Article in European journal of clinical investigation, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 22 papers, 2 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
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.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
22 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Strength of association between comorbidities and asthma: a meta-analysis.European respiratory review : an official journal of the European Respiratory Society · 2023Pooled it
- Effects of tryptophan, serotonin, and kynurenine on ischemic heart diseases and its risk factors: a Mendelian Randomization study.European journal of clinical nutrition · 2020Pooled it
- Causality and Association: Two Terms to Use and Interpret Judiciously.Indian dermatology online journal · 2026Article
- Review
- Unveiling the Genetic Association Between Hemoglobin Concentration and Amyotrophic Lateral Sclerosis.Brain and behavior · 2026Article
- Association between timeliness of detection, notification and response and the magnitude, severity and duration of disease outbreaks: a retrospective review of 84 outbreaks in Uganda, 2017-2022.BMJ global health · 2025Article
- Are all sugars equal? Role of the food source in physiological responses to sugars with an emphasis on fruit and fruit juice.European journal of nutrition · 2024Review
- Misstatements, misperceptions, and mistakes in controlling for covariates in observational research.eLife · 2024Review
- Does positive feedback or appraisal about medical providers increase patients' trust and lead to better treatment outcomes? A double-blind randomized control trial.Journal of physical therapy science · 2023Article
- Melanoma and CLL co-occurrence and survival: role of KC history.BMC cancer · 2023Article
- Causal models and causal modelling in obesity: foundations, methods and evidence.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2023Review
- Which Factors Influence Healthy Aging? A Lesson from the Longevity Village of Bama in China.Aging and disease · 2023Review
- The Relative Merits of Observational and Experimental Research: Four Key Principles for Optimising Observational Research Designs.Nutrients · 2022Article
- Risk of Type 2 Diabetes Among Individuals with Excess Weight: Weight Trajectory Effects.Current diabetes reports · 2022Review
- Fasting blood glucose as a predictor of mortality: Lost in translation.Cell metabolism · 2021Article
- Detection of significant antiviral drug effects on COVID-19 with reasonable sample sizes in randomized controlled trials: A modeling study.PLoS medicine · 2021Article
- Potential Cardiometabolic Health Benefits of Full-Fat Dairy: The Evidence Base.Advances in nutrition (Bethesda, Md.) · 2020Article
- Article
- Best Practices for Conducting Observational Research to Assess the Relation between Nutrition and Bone: An International Working Group Summary.Advances in nutrition (Bethesda, Md.) · 2019Article
- Weight Cycling Increases Longevity Compared with Sustained Obesity in Mice.Obesity (Silver Spring, Md.) · 2018Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
10 authors.
Funding
Abstract
backgroundDiffering opinions exist on whether associations obtained in observational studies can be reliable indicators of a causal effect if the observational study is sufficiently well controlled and executed. MATERIALS AND
methodsTo test this, we conducted two animal observational studies that were rigorously controlled and executed beyond what is achieved in studies of humans. In study 1, we randomized 332 genetically identical C57BL/6J mice into three diet groups with differing food energy allotments and recorded individual self-selected daily energy intake and lifespan. In study 2, 60 male mice (CD1) were paired and divided into two groups for a 2-week feeding regimen. We evaluated the association between weight gain and food consumption. Within each pair, one animal was randomly assigned to an S group in which the animals had free access to food. The second paired animal (R group) was provided exactly the same diet that their S partner ate the day before.
resultsIn study 1, across all three groups, we found a significant negative effect of energy intake on lifespan. However, we found a positive association between food intake and lifespan among the ad libitum feeding group: 29·99 (95% CI: 8·2-51·7) days per daily kcal. In study 2, we found a significant (P = 0·003) group (randomized vs. self-selected)-by-food consumption interaction effect on weight gain.
conclusionAt least in nutrition research, associations derived from observational studies may not be reliable indicators of causal effects, even with the most rigorous study designs achievable.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.