Evidence map›Paper›PMID 34793435›Full record

ArticlePLoS computational biology2021

The meaning of significant mean group differences for biomarker discovery.

Eva Loth, Jumana Ahmad, Chris Chatham, Beatriz López, Ben Carter, Daisy Crawley, Bethany Oakley, Hannah Hayward, Jennifer Cooke, Antonia San José Cáceres and 9 more

Abstract read
In one paragraph

Article in PLoS computational biology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 26 papers, 5 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
26citing papers in PubMed, 5 pooled it
–field-weighted citation impact
1 · What the graph read from 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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

26 citing papers in PubMed, 5 syntheses or guidelines pooled it.

  1. Pooled it
  2. Pooled it
  3. Social motor synchrony in autism spectrum conditions: A systematic review.Autism : the international journal of research and practice · 2024
    Pooled it
  4. Pooled it
  5. Pooled it
  6. Label-free optical biomarker for prostate cancer diagnosis.Molecular medicine (Cambridge, Mass.) · 2026
    Article
  7. Review
  8. Article
  9. Novel therapeutics in autism spectrum disorder.Neurotherapeutics : the journal of the American Society for Experimental NeuroTherapeutics · 2026
    Review
  10. Article
  11. Article
  12. Review
  13. Article
  14. Review
  15. Article
  16. Brain glutathione and GABA+ levels in autistic children.Autism research : official journal of the International Society for Autism Research · 2024
    Article
  17. Article
  18. Article
  19. Candidate diagnostic biomarkers for neurodevelopmental disorders in children and adolescents: a systematic review.World psychiatry : official journal of the World Psychiatric Association (WPA) · 2023
    Article
  20. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

19 authors.

Eva LothDepartment of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.ORCID 0000-0001-9458-9167
Jumana AhmadDepartment of Psychology, Social Work and Counselling, Faculty of Education and Health, University of Greenwich, London, United Kingdom.ORCID 0000-0001-5271-0731
Chris ChathamNeuroscience & Rare Diseases, Pharma Research & Early Development, Roche Innovation Center New York, New York, United States of America.ORCID 0000-0003-4427-8285
Beatriz LópezDepartment of Psychology, Portsmouth University, Portsmouth, United Kingdom.ORCID 0000-0001-5621-6044
Ben CarterDepartment of Biostatistics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.ORCID 0000-0003-0318-8865
Daisy CrawleyDepartment of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.ORCID 0000-0001-9901-1110
Bethany OakleyDepartment of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.ORCID 0000-0002-1968-134X
Hannah HaywardDepartment of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.ORCID 0000-0001-5552-2146
Jennifer CookeDepartment of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.ORCID 0000-0001-6832-3998
Antonia San José CáceresDepartment of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.ORCID 0000-0002-1451-4948
Danilo BzdokDepartment of Biomedical Engineering, McConnell Brain-Imaging Centre (BIC), Montreal Neurological Institute (MNI), Faculty of Medicine, McGill University, Montreal, Canada.ORCID 0000-0003-3466-6620
Emily JonesCentre for Brain and Cognitive Development, Birkbeck, University of London, London, United Kingdom.ORCID 0000-0001-5747-9540
Tony CharmanDepartment of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.ORCID 0000-0003-1993-6549
Christian BeckmannDepartment of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, the Netherlands.
Thomas BourgeronHuman Genetics and Cognitive Functions, Institut Pasteur, UMR3571 CNRS, Université de Paris, Paris, France.ORCID 0000-0001-8164-9220
Roberto ToroHuman Genetics and Cognitive Functions, Institut Pasteur, UMR3571 CNRS, Université de Paris, Paris, France.ORCID 0000-0002-6671-858X
Jan BuitelaarDepartment of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, the Netherlands.
Declan MurphyDepartment of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.ORCID 0000-0002-6664-7451
Guillaume DumasMila-Quebec Artificial Intelligence Institute, Montreal, Canada.ORCID 0000-0002-2253-1844

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Over the past decade, biomarker discovery has become a key goal in psychiatry to aid in the more reliable diagnosis and prognosis of heterogeneous psychiatric conditions and the development of tailored therapies. Nevertheless, the prevailing statistical approach is still the mean group comparison between "cases" and "controls," which tends to ignore within-group variability. In this educational article, we used empirical data simulations to investigate how effect size, sample size, and the shape of distributions impact the interpretation of mean group differences for biomarker discovery. We then applied these statistical criteria to evaluate biomarker discovery in one area of psychiatric research-autism research. Across the most influential areas of autism research, effect size estimates ranged from small (d = 0.21, anatomical structure) to medium (d = 0.36 electrophysiology, d = 0.5, eye-tracking) to large (d = 1.1 theory of mind). We show that in normal distributions, this translates to approximately 45% to 63% of cases performing within 1 standard deviation (SD) of the typical range, i.e., they do not have a deficit/atypicality in a statistical sense. For a measure to have diagnostic utility as defined by 80% sensitivity and 80% specificity, Cohen's d of 1.66 is required, with still 40% of cases falling within 1 SD. However, in both normal and nonnormal distributions, 1 (skewness) or 2 (platykurtic, bimodal) biologically plausible subgroups may exist despite small or even nonsignificant mean group differences. This conclusion drastically contrasts the way mean group differences are frequently reported. Over 95% of studies omitted the "on average" when summarising their findings in their abstracts ("autistic people have deficits in X"), which can be misleading as it implies that the group-level difference applies to all individuals in that group. We outline practical approaches and steps for researchers to explore mean group comparisons for the discovery of stratification biomarkers.

Indexed as

Autistic DisorderBiomarkersCase-Control StudiesComputational BiologyComputer SimulationHumansIndividualityMental DisordersNeurodevelopmental DisordersNeuropsychiatryNeuropsychologyNormal DistributionSample SizeBiomarkers

Identifiers

PMID34793435
PMCPMC8601419

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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.