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The Prostate Cancer Prevention Trial: Design, Biases and Interpretation of Study Results

2006; Lippincott Williams & Wilkins; Volume: 175; Issue: 6 Linguagem: Inglês

10.1016/s0022-5347(06)00284-9

1527-3792

Phyllis J. Goodman, Ian M. Thompson, Catherine M. Tangen, John J. Crowley, Leslie G. Ford, Charles A. Coltman,

Prostate Cancer Treatment and Research

No AccessJournal of UrologyAdult urology1 Jun 2006The Prostate Cancer Prevention Trial: Design, Biases and Interpretation of Study Results Phyllis J. Goodman, Ian M. Thompson, Catherine M. Tangen, John J. Crowley, Leslie G. Ford, and Charles A. Coltman Phyllis J. GoodmanPhyllis J. Goodman Southwest Oncology Group Statistical Center, Seattle, Washington More articles by this author , Ian M. ThompsonIan M. Thompson University of Texas Health Science Center, San Antonio, Texas Financial interest and/or other relationship with Mission Pharmaceutical, AstraZeneca, Predicant, V-Targos and GlaxoSmithKline. More articles by this author , Catherine M. TangenCatherine M. Tangen Southwest Oncology Group Statistical Center, Seattle, Washington More articles by this author , John J. CrowleyJohn J. Crowley Southwest Oncology Group Statistical Center, Seattle, Washington More articles by this author , Leslie G. FordLeslie G. Ford National Cancer Institute, Bethesda, Maryland More articles by this author , and Charles A. ColtmanCharles A. Coltman Southwest Oncology Group Operations Office, San Antonio, Texas More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(06)00284-9AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: We describe the complexities of the study design of the PCPT and how they influenced the end point chosen, trial implementation, analysis and interpretation of the results. Materials and Methods: Data from the PCPT are provided to evaluate and quantify the potential biases of this trial design. Results: Six potential sources of bias, including prostate specific antigen, digital rectal examination, prostate biopsy technique, study medication nonadherence and contamination, and transurethral prostate resection are presented. These biases resulted in the need for the end of study biopsy to evaluate the trial objectives. Conclusions: There were a large number of known and potential biases that worked for and against finasteride. Because of the trial design and inherent biases, it is imperative that interim biopsy results should be interpreted with caution. While the period prevalence end point that relied on an end of study biopsy was perhaps not the most clinically relevant, it was the only way to remove as much bias as possible and meet the study objective of determining if finasteride could decrease the risk of prostate cancer. The success of the PCPT depended on constant scrutiny by the Data and Safety Monitoring Committee to monitor these biases. The design and biopsy assumptions outlined at the inception of the trial were met, including adherence and contamination rates, the for-cause biopsy rate and the final percent of men with study end points. 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Google Scholar © 2006 by American Urological AssociationFiguresReferencesRelatedDetailsCited ByTaneja S (2018) Re: Long-Term Survival of Participants in the Prostate Cancer Prevention TrialJournal of Urology, VOL. 191, NO. 2, (358-361), Online publication date: 1-Feb-2014.Thompson I, Tangen C, Goodman P, Lucia M, Parnes H, Lippman S and Coltman C (2018) Finasteride Improves the Sensitivity of Digital Rectal Examination for Prostate Cancer DetectionJournal of Urology, VOL. 177, NO. 5, (1749-1752), Online publication date: 1-May-2007. Volume 175Issue 6June 2006Page: 2234-2242 Advertisement Copyright & Permissions© 2006 by American Urological AssociationKeywordsprostatic neoplasmsresearch designprostatebias (epidemiology)biopsyMetricsAuthor Information Phyllis J. Goodman Southwest Oncology Group Statistical Center, Seattle, Washington More articles by this author Ian M. Thompson University of Texas Health Science Center, San Antonio, Texas Financial interest and/or other relationship with Mission Pharmaceutical, AstraZeneca, Predicant, V-Targos and GlaxoSmithKline. More articles by this author Catherine M. Tangen Southwest Oncology Group Statistical Center, Seattle, Washington More articles by this author John J. Crowley Southwest Oncology Group Statistical Center, Seattle, Washington More articles by this author Leslie G. Ford National Cancer Institute, Bethesda, Maryland More articles by this author Charles A. Coltman Southwest Oncology Group Operations Office, San Antonio, Texas More articles by this author Expand All Advertisement PDF DownloadLoading ...