title: Baseline subject characteristics predictive of compliance with study-mandated prostate biopsy in men at risk of prostate cancer: results from REDUCE.
abstract: Study compliance is crucial when the study outcome is determined by an invasive procedure, such as prostate biopsy. To investigate predictors of compliance in study-mandated prostate biopsies, we analyzed demographic, clinical and reported lifestyle data from the REDUCE trial.
  
  
  
  We retrospectively identified 8025 men from REDUCE with at least 2 years of follow-up, and used multivariable logistic regression to test the association between baseline demographic and clinical characteristics and undergoing the study-mandated prostate biopsy at 2 years. We then examined whether missing any of these data was associated with undergoing a biopsy.
  
  
  
  In REDUCE, 22% of men did not undergo a 2-year biopsy. On multivariable analysis, the non-North American region was predictive of 42-44% increased likelihood of undergoing a 2-year biopsy (P⩽0.001). Being enrolled at a center that enrolled >10 subjects (2nd and 3rd tertile) was associated with a 42-48% increased likelihood of undergoing a 2-year biopsy (P<0.001). In addition, black race predicted 44% lower rate of on-study 2-year biopsy (odds ratio (OR)=0.56; P=0.001). Finally, missing one or more baseline variables was associated with a 32% decreased likelihood of undergoing a 2-year biopsy (OR=0.68; P<0.001).
  
  
  
  In REDUCE, men outside North America, those at higher volume centers and those with complete baseline data were more likely to undergo study-mandated 2-year biopsies. Given prostate biopsy is becoming increasingly utilized as an endpoint in trials that are often multi-national, regional differences in compliance should be considered when designing future trials. Likewise, efforts are needed to ensure compliance in low-volume centers or among subjects missing baseline data.
authors.affiliation: Division of Urology, Department of Surgery, Duke University School of Medicine, Durham, NC, USA.|Surgery Section, Durham VA Medical Center, Durham, NC, USA.
authors.forename: S
authors.initials: S
authors.lastname: Fischer
authors.affiliation: Surgery Section, Durham VA Medical Center, Durham, NC, USA.|Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC, USA.
authors.forename: S
authors.initials: S
authors.lastname: Sun
authors.affiliation: Surgery Section, Durham VA Medical Center, Durham, NC, USA.|Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC, USA.
authors.forename: L E
authors.initials: LE
authors.lastname: Howard
authors.affiliation: Department of Urology, Mayo Clinic, Rochester, MN, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Moreira
authors.affiliation: GlaxoSmithKline Inc., R&D Unit, King of Prussia, PA, USA.
authors.forename: R
authors.initials: R
authors.lastname: Castro-Santamaria
authors.affiliation: Washington University School of Medicine in St. Louis, St. Louis, MI, USA.
authors.forename: G L
authors.initials: GL
authors.lastname: Andriole
authors.affiliation: Surgery Section, Durham VA Medical Center, Durham, NC, USA.|Division of Urology, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
authors.forename: A C
authors.initials: AC
authors.lastname: Vidal
authors.affiliation: Surgery Section, Durham VA Medical Center, Durham, NC, USA.|Division of Urology, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Freedland
mesh_terms: D000368:Aged; D001706:Biopsy; D015897:Comorbidity; D006801:Humans; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D016017:Odds Ratio; D010349:Patient Compliance; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000473:pathology*; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D012306:Risk