Evidence map›Paper›PMID 40624575›Full record

ArticleDiagnostic and prognostic research2025

A decomposition of Fisher's information to inform sample size for developing or updating fair and precise clinical prediction models for individual risk-part 1: binary outcomes.

Richard D Riley, Gary S Collins, Rebecca Whittle, Lucinda Archer, Kym I E Snell, Paula Dhiman, Laura Kirton, Amardeep Legha, Xiaoxuan Liu, Alastair K Denniston and 4 more

Abstract read
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Article in Diagnostic and prognostic research, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed, 1 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

5 citing papers in PubMed, 1 synthesis or guideline pooled it.

  1. Pooled it
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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

14 authors.

Richard D RileyDepartment of Applied Health Sciences, School of Health Sciences, College of Medicine and Health, University of Birmingham, Birmingham, UK. r.d.riley@bham.ac.uk.
Gary S CollinsCentre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, OX3 7LD, UK.
Rebecca WhittleDepartment of Applied Health Sciences, School of Health Sciences, College of Medicine and Health, University of Birmingham, Birmingham, UK.
Lucinda ArcherDepartment of Applied Health Sciences, School of Health Sciences, College of Medicine and Health, University of Birmingham, Birmingham, UK.
Kym I E SnellDepartment of Applied Health Sciences, School of Health Sciences, College of Medicine and Health, University of Birmingham, Birmingham, UK.
Paula DhimanCentre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, OX3 7LD, UK.
Laura KirtonCancer Research UK Clinical Trials Unit, Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.
Amardeep LeghaDepartment of Applied Health Sciences, School of Health Sciences, College of Medicine and Health, University of Birmingham, Birmingham, UK.
Xiaoxuan LiuNational Institute for Health and Care Research (NIHR) Birmingham Biomedical Research Centre, Birmingham, UK.
Alastair K DennistonNational Institute for Health and Care Research (NIHR) Birmingham Biomedical Research Centre, Birmingham, UK.
Frank E HarrellDepartment of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN, USA.
Laure WynantsDepartment of Epidemiology, Care and Public Health Research Institute (CAPHRI), Maastricht University, Maastricht, The Netherlands.
Glen P MartinDivision of Informatics, Imaging and Data Science, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK.
Joie EnsorDepartment of Applied Health Sciences, School of Health Sciences, College of Medicine and Health, University of Birmingham, Birmingham, UK.

Funding

Cancer Research UK C49297/A27294Cancer Research UK CTUQQR-Dec22/100006Cancer Research UK PRCPJT-Nov21\100021EPSRC EP/Y018516/1MRC MR/T025085/1MRC-NIHR MR/Z503873/1National Institute for Health and Care Research NIHR303331U.S. National Center for Advancing Translational Sciences (NCATS) Clinical Translational Science Award (CTSA) Program 5UL1TR002243
6 · The paper itself

Abstract

backgroundWhen using a dataset to develop or update a clinical prediction model, small sample sizes increase concerns of overfitting, instability, poor predictive performance and a lack of fairness. For models estimating the risk of a binary outcome, previous research has outlined sample size calculations that target low overfitting and a precise overall risk estimate. However, more guidance is needed for targeting precise and fair individual-level risk estimates.

methodsWe propose a decomposition of Fisher's information matrix to help examine sample sizes required for developing or updating a model, aiming for precise and fair individual-level risk estimates. We outline a five-step process for use before data collection or when an existing dataset or pilot study is available. It requires researchers to specify the overall risk in the target population, the (anticipated) distribution of key predictors in the model and an assumed 'core model' either specified directly (i.e. a logistic regression equation is provided) or based on a specified C-statistic and relative effects of (standardised) predictors.

resultsWe produce closed-form solutions that decompose the variance of an individual's risk estimate into the Fisher's unit information matrix, predictor values and the total sample size. This allows researchers to quickly calculate and examine the anticipated precision of individual-level predictions and classifications for specified sample sizes. The information can be presented to key stakeholders (e.g. health professionals, patients, grant funders) to inform target sample sizes for prospective data collection or whether an existing dataset is sufficient. Our proposal is implemented in our new software module pmstabilityss. We provide two real examples and emphasise the importance of clinical context, including any risk thresholds for decision making and fairness checks.

conclusionsOur approach helps researchers examine potential sample sizes required to target precise and fair individual-level predictions when developing or updating prediction models for binary outcomes.

Indexed as

ClassificationClinical prediction modelsFairnessFisher’s information matrixInstabilitySample sizeUncertainty intervals

Identifiers

PMID40624575
PMCPMC12235806

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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.