title: Adherence to colorectal cancer screening: a randomized clinical trial of competing strategies.
abstract: BACKGROUND
  Despite evidence that several colorectal cancer (CRC) screening strategies can reduce CRC mortality, screening rates remain low. This study aimed to determine whether the approach by which screening is recommended influences adherence.
  
  
  METHODS
  We used a cluster randomization design with clinic time block as the unit of randomization. Persons at average risk for development of CRC in a racially/ethnically diverse urban setting were randomized to receive recommendation for screening by fecal occult blood testing (FOBT), colonoscopy, or their choice of FOBT or colonoscopy. The primary outcome was completion of CRC screening within 12 months after enrollment, defined as performance of colonoscopy, or 3 FOBT cards plus colonoscopy for any positive FOBT result. Secondary analyses evaluated sociodemographic factors associated with completion of screening.
  
  
  RESULTS
  A total of 997 participants were enrolled; 58% completed the CRC screening strategy they were assigned or chose. However, participants who were recommended colonoscopy completed screening at a significantly lower rate (38%) than participants who were recommended FOBT (67%) (P < .001) or given a choice between FOBT or colonoscopy (69%) (P < .001). Latinos and Asians (primarily Chinese) completed screening more often than African Americans. Moreover, nonwhite participants adhered more often to FOBT, while white participants adhered more often to colonoscopy.
  
  
  CONCLUSIONS
  The common practice of universally recommending colonoscopy may reduce adherence to CRC screening, especially among racial/ethnic minorities. Significant variation in overall and strategy-specific adherence exists between racial/ethnic groups; however, this may be a proxy for health beliefs and/or language. These results suggest that patient preferences should be considered when making CRC screening recommendations. Trial Registration  clinicaltrials.gov Identifier: NCT00705731.
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA. jinadomi@medicine.washington.edu
authors.forename: John M
authors.initials: JM
authors.lastname: Inadomi
authors.forename: Sandeep
authors.initials: S
authors.lastname: Vijan
authors.forename: Nancy K
authors.initials: NK
authors.lastname: Janz
authors.forename: Angela
authors.initials: A
authors.lastname: Fagerlin
authors.forename: Jennifer P
authors.initials: JP
authors.lastname: Thomas
authors.forename: Yunghui V
authors.initials: YV
authors.lastname: Lin
authors.forename: Roxana
authors.initials: R
authors.lastname: Muñoz
authors.forename: Chim
authors.initials: C
authors.lastname: Lau
authors.forename: Ma
authors.initials: M
authors.lastname: Somsouk
authors.forename: Najwa
authors.initials: N
authors.lastname: El-Nachef
authors.forename: Rodney A
authors.initials: RA
authors.lastname: Hayward
mesh_terms: D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D001213:Asian / Q000706:statistics & numerical data; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000517:prevention & control*; D055088:Early Detection of Cancer / Q000379:methods; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D015999:Multivariate Analysis; D009780:Occult Blood; D010349:Patient Compliance / Q000706:statistics & numerical data*; D012307:Risk Factors; D012812:Sigmoidoscopy; D044465:White People / Q000706:statistics & numerical data