{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T15:12:42Z","timestamp":1785510762774,"version":"3.56.0"},"reference-count":14,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T00:00:00Z","timestamp":1764806400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neuroimaging"],"abstract":"<jats:p>\n                    Randomized controlled trials (RCTs) are essential for evaluating treatment efficacy, typically comparing active interventions to control conditions. In situations where blinding is impractical\u2014such as in psychological therapies or physical rehabilitation\u2014waitlist controls are often used to account for natural symptom progression and test\u2013retest variability. This study examines the biases introduced by\n                    <jats:italic>post-hoc<\/jats:italic>\n                    analyses under conditions of low statistical power, particularly in neuroimaging research. Through large-scale simulations involving 100 million datasets with varying sample sizes, treatment effects, and test\u2013retest variability, the study demonstrates that the common practice of conducting\n                    <jats:italic>post-hoc<\/jats:italic>\n                    tests only on brain regions showing significant interaction effects can substantially increase the false positive rate in the control condition. These findings underscore the relevance of Berkson\u2019s paradox in interpreting unexpected control group outcomes and caution against overinterpreting such results. A complementary neuroimaging simulation reinforces these conclusions, emphasizing the need for critical scrutiny when evaluating significant effects in control groups. Overall, this work challenges conventional\n                    <jats:italic>post-hoc<\/jats:italic>\n                    testing strategies and advocates for a more nuanced and statistically informed interpretation of results, especially in studies with limited power.\n                  <\/jats:p>","DOI":"10.3389\/fnimg.2025.1637148","type":"journal-article","created":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T14:32:51Z","timestamp":1764858771000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Understanding false positives in control conditions: a simulation study of post-hoc testing in low-powered neuroimaging trials"],"prefix":"10.3389","volume":"4","author":[{"given":"Ji Hyun","family":"Ko","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,12,4]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"289","DOI":"10.1111\/j.2517-6161.1995.tb02031.x","article-title":"Controlling the false discovery rate: a practical and powerful approach to multiple testing","volume":"57","author":"Benjamini","year":"1995","journal-title":"J. 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Sci."},{"key":"ref11","doi-asserted-by":"publisher","first-page":"46088","DOI":"10.1038\/srep46088","article-title":"Dynamic default mode network across different brain states","volume":"7","author":"Lin","year":"2017","journal-title":"Sci. Rep."},{"key":"ref12","doi-asserted-by":"publisher","first-page":"1044","DOI":"10.1016\/j.neuroimage.2011.06.075","article-title":"A whole-brain voxel based measure of intrinsic connectivity contrast reveals local changes in tissue connectivity with anesthetic without a priori assumptions on thresholds or regions of interest","volume":"58","author":"Martuzzi","year":"2011","journal-title":"NeuroImage"},{"key":"ref13","doi-asserted-by":"publisher","first-page":"274","DOI":"10.1111\/j.1745-6924.2009.01125.x","article-title":"Puzzlingly high correlations in fMRI studies of emotion, personality, and social cognition","volume":"4","author":"Vul","year":"2009","journal-title":"Perspect. Psychol. Sci."},{"key":"ref14","doi-asserted-by":"publisher","first-page":"125","DOI":"10.1089\/brain.2012.0073","article-title":"Conn: a functional connectivity toolbox for correlated and anticorrelated brain networks","volume":"2","author":"Whitfield-Gabrieli","year":"2012","journal-title":"Brain Connect."}],"container-title":["Frontiers in Neuroimaging"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fnimg.2025.1637148\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T14:32:52Z","timestamp":1764858772000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fnimg.2025.1637148\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12,4]]},"references-count":14,"alternative-id":["10.3389\/fnimg.2025.1637148"],"URL":"https:\/\/doi.org\/10.3389\/fnimg.2025.1637148","relation":{},"ISSN":["2813-1193"],"issn-type":[{"value":"2813-1193","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,12,4]]},"article-number":"1637148"}}