Cited by 84Gene expression and cancer classificationMachine Learning and Data ClassificationBreast Cancer Treatment Studies

Batch Effect Confounding Leads to Strong Bias in Performance Estimates Obtained by Cross-Validation

Open access
Soneson, Charlotte, Gerster, Sarah, Delorenzi, Mauro·2014·PLoS ONE

Abstract

BACKGROUND: With the large amount of biological data that is currently publicly available, many investigators combine multiple data sets to increase the sample size and potentially also the power of their analyses. However, technical differences ("batch effects") as well as differences in sample composition between the data sets may significantly affect the ability to draw generalizable conclusions from such studies. FOCUS: The current study focuses on the construction of classifiers, and the use of cross-validation to estimate their performance. In particular, we investigate the impact of batch effects and differences in sample composition between batches on the accuracy of the classification performance estimate obtained via cross-validation. The focus on estimation bias is a main difference compared to previous studies, which have mostly focused on the predictive performance and how it relates to the presence of batch effects. DATA: We work on simulated data sets. To have realistic intensity distributions, we use real gene expression data as the basis for our simulation. Random samples from this expression matrix are selected and assigned to group 1 (e.g., 'control') or group 2 (e.g., 'treated'). We introduce batch effects and select some features to be differentially expressed between the two groups. We consider several scenarios for our study, most importantly different levels of confounding between groups and batch effects. METHODS: We focus on well-known classifiers: logistic regression, Support Vector Machines (SVM), k-nearest neighbors (kNN) and Random Forests (RF). Feature selection is performed with the Wilcoxon test or the lasso. Parameter tuning and feature selection, as well as the estimation of the prediction performance of each classifier, is performed within a nested cross-validation scheme. The estimated classification performance is then compared to what is obtained when applying the classifier to independent data.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1371/journal.pone.0100335

Cites

5 of 5 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Batch effects make it difficult to draw conclusions from data across experimental batches.

    “These batch effects make it difficult to draw conclusions from data across experimental batches (Leek et al., 2010; Parker and Leek, 2012; Soneson et al., 2014; Nygaard et al., 2016; Caicedo et al., 2017).”

    From WILDS: A Benchmark of in-the-Wild Distribution Shifts (2020) · cites this paper as Soneson et al., 2014

  • Measurements from high-throughput screens are confounded by technical artifacts that arise from differences in the execution of each batch.

    “Despite attempts to carefully control experimental variables such as temperature, humidity, and reagent concentration, measurements from these screens are confounded by technical artifacts that arise from differences in the execution of each batch.”

    From WILDS: A Benchmark of in-the-Wild Distribution Shifts (2020) · cites this paper as Soneson et al., 2014

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 27

  1. [1]Edgar R, Domrachev M, Lash AE (2002) Gene Expression Omnibus: NCBI gene expression and hybridization array data repository. Nucleic Acids Research 30: 207– 10. 11752295 PMC99122
  2. [2]Brazma A, Parkinson H, Sarkans U, Shojatalab M, Vilo J, et al (2003) ArrayExpress – a public repository for microarray gene expression data at the EBI. Nucleic Acids Research 31: 68– 71. 12519949 PMC165538
  3. [3]Lukk M, Kapushesky M, Nikkila J, Parkinson H, Goncalves A, et al (2010) A global map of human gene expression. Nat Biotech 28: 322– 324. PMC2974261 20379172
  4. [4]Brown PO, Botstein D (1999) Exploring the new world of the genome with DNA microarrays. Nature Genetics 21: 33– 37. 9915498
  5. [5]Scherer A (2009) Batch Effects and Noise in Microarray Experiments: Sources and Solutions. Wiley Series in Probability and Statistics. Wiley. Available: http://books.google.ch/books?id=3-8MsCiPqnkC.
  6. [8]Luo J, Schumacher M, Scherer A, Sanoudou D, Megherbi D, et al (2010) A comparison of batch effect removal methods for enhancement of prediction performance using MAQC-II microarray gene expression data. Pharmacogenomics J 10: 278– 91. 20676067 PMC2920074
  7. [9]Kerr MK, Churchill GA (2001) Experimental design for gene expression microarrays. Biostatistics 2: 183– 201. 12933549
  8. [10]Akey JM, Biswas S, Leek JT, Storey JD (2007) On the design and analysis of gene expression studies in human populations. Nat Genet 39: 807– 808. 17597765
  9. [11]Parker HS, Leek J (2012) The practical effect of batch on genomic prediction. Statistical Applications in Genetics and Molecular Biology 11: Article– 10. PMC3760371 22611599
  10. [12]Boulesteix AL, Strobl C (2009) Optimal classifier selection and negative bias in error rate estimation: an empirical study on high-dimensional prediction. BMC Med Res Methodol 9: 85. 20025773 PMC2813849
  11. [14]Ambroise C, McLachlan GJ (2002) Selection bias in gene extraction on the basis of microarray gene-expression data. Proceedings of the National Academy of Sciences 99: 6562– 6566. PMC124442 11983868
  12. [15]Radmacher MD, McShane LM, Simon R (2002) A Paradigm for Class Prediction Using Gene Expression Profiles. Journal of Computational Biology 9: 505– 511. 12162889
  13. [16]Simon R, Radmacher MD, Dobblin K, McShane LM (2003) Pitfalls in the Use of DNA Microarray Data for Diagnostic and Prognostic Classification. Journal of the National Cancer Institute 95: 14– 18. 12509396
  14. [17]Molinaro AM, Simon R, Pfeiffer RM (2005) Prediction error estimation: a comparison of resampling methods. Bioinformatics 21: 3301– 7. 15905277
  15. [19]Wood IA, Visscher PM, Mengersen KL (2007) Classification based upon gene expression data: bias and precision of error rates. Bioinformatics 23: 1363– 70. 17392326
  16. [21]Alter O, Brown PO, Botstein D (2000) Singular value decomposition for genome-wide expression data processing and modeling. Proceedings of the National Academy of Sciences 97: 10101– 10106. PMC27718 10963673
  17. [22]Benito M, Parker J, Du Q, Wu J, Xiang D, et al (2004) Adjustment of systematic microarray data biases. Bioinformatics 20: 105– 114. 14693816
  18. [23]Johnson W, Li C, Rabinovic A (2006) Adjusting batch effects in microarray expression data using empirical Bayes methods. Biostatistics 8: 118– 27. 16632515
  19. [24]Sims AH, Smethurst GJ, Hey Y, Okoniewski MJ, Pepper SD, et al (2008) The removal of multiplicative, systematic bias allows integration of breast cancer gene expression datasets – improving meta-analysis and prediction of prognosis. BMC Med Genomics 1: 42. 18803878 PMC2563019
  20. [25]Chen C, Grennan K, Badner J, Zhang D, Gershon E, et al (2011) Removing batch effects in analysis of expression microarray data: an evaluation of six batch adjustment methods. PLoS ONE 6: e17238. 21386892 PMC3046121
  21. [27]Gagnon-Bartsch J, Speed TP (2012) Using control genes to correct for unwanted variation in microarray data. Biostatistics 13: 539– 552. 22101192 PMC3577104
  22. [28]Van Cutsem E, Labianca R, Bodoky G, Barone C, Aranda E, et al (2009) Randomized Phase III Trial Comparing Biweekly Infusional Fluorouracil/Leucovorin Alone or With Irinotecan in the Adjuvant Treatment of Stage III Colon Cancer: PETACC-3. Journal of Clinical Oncology 27: 3117– 3125. 19451425
  23. [30]James G, Hastie T, Witten D, Tibshirani R (2013) An Introduction to Statistical Learning: With Applications in R. Springer Texts in Statistics. Springer London, Limited.
  24. [37]Ben-Hur A, Ong CS, Sonnenburg S, Schölkopf B, Rätsch G (2008) Support vector machines and kernels for computational biology. PLoS Computational Biology 4. PMC2547983 18974822
  25. [38]Tibshirani R (1996) Regression shrinkage and selection via the lasso. Journal of the Royal Statistical Society (Series B) 58: 267– 288.
  26. [39]Sadanandam A, Lyssiotis CA, Homicsko K, Collisson EA, Gibb WJ, et al (2013) A colorectal cancer classification system that associates cellular phenotype and responses to therapy. Nature Medicine 19: 619– 625. PMC3774607 23584089
  27. [40]Budinska E, Popovici V, Tejpar S, D'Ario G, Lapique N, et al (2013) Gene expression patterns unveil a new level of molecular heterogeneity in colorectal cancer. The Journal of Pathology 231: 63– 76. 23836465 PMC3840702

Cited by

Sorted by citations

Authors
Soneson, C., Gerster, S., & Delorenzi, M.
Affiliations
SIB Swiss Institute of Bioinformatics (CH)
Corresponding author
Soneson, Charlotte
Venue
PLoS ONE
Published
2014-06-26
Volume
9
Issue
6
Pages
e100335
ISSN
1932-6203 (ISSN-L)
OpenAlex
W2084680372
Cited by
84
References
5
Citations by year
2026: 12 · 2025: 13 · 2024: 10 · 2023: 10 · 2022: 6 · 2021: 7 · 2020: 8 · 2018: 7 · 2017: 5 · 2016: 3 · 2015: 3
FWCI
1.50
Type
journal article
Language
en
Open access
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • IRIS (submittedVersion)
  • RePEc: Research Papers in Economics (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Figshare (submittedVersion, cc-by)
  • SERVAL (Université de Lausanne) (submittedVersion, other-oa)
Funders
  • National Science Foundation
  • Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (135421, 320030)
  • Fondation Medic
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Gene expression and cancer classification
  • Physical Sciences › Computer Science › Artificial Intelligence › Machine Learning and Data Classification
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cancer Research › Breast Cancer Treatment Studies
Keywords
batch effects, confounding, cross-validation, estimation bias, gene expression data, nested cross-validation, support vector machine, random forest, k-nearest neighbors, logistic regression, LASSO feature selection, Wilcoxon test, data combination
MeSH terms
Artificial Intelligence, Statistics as Topic, Reproducibility of Results, Bias, Computational Biology, Gene Expression Profiling

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review