title: Estimation of the Adenoma Detection Rate From the Polyp Detection Rate by Using a Conversion Factor in a Predominantly Hispanic Population.
abstract: BACKGROUND
  Calculating the adenoma detection rate (ADR) is a complex process in contrast to the polyp detection rate (PDR) that can be easily calculated. The average adenoma to polyp detection rate quotient (APDRQ) was proposed as a conversion factor to estimate the ADR for individual endoscopists from the endoscopist's PDR. However, this conversion factor was not validated in different practice settings.
  
  
  OBJECTIVE
  To validate the use of the proposed conversion factor in a practice setting with a predominantly Hispanic population.
  
  
  METHODS
  We conducted a retrospective, cross-sectional study (December 2007 to November 2012) of screening colonoscopies at a university practice setting with an 86.9% Hispanic population. The actual ADR and PDR were calculated for all endoscopists. The weighted average of ADR to PDR ratio for each endoscopist was used to obtain APDRQ. The APDRQ was used as a conversion multiplier to estimate each endoscopist's ADR using the single endoscopist's PDR.
  
  
  RESULTS
  A total of 2148 screening colonoscopies were included. The average PDR for the whole group was 36.9% (range, 11% to 49%). The actual ADR was estimated as 25.5% (range, 11% to 37%). The average APDRQ for our group was 0.68. The estimated ADR was 25.48% (range, 8% to 33%). There was a high correlation between actual ADR and the estimated ADR (Pearson correlation=0.92).
  
  
  CONCLUSIONS
  In a practice setting with a predominantly Hispanic population, a conversion factor can be used to estimate ADR from PDR providing a high degree of correlation with the actual ADR.
authors.affiliation: *Department of Internal Medicine, Division of Gastroenterology †Department of Biomedical Sciences, Division of Biostatistics & Epidemiology, Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center, El Paso, TX.
authors.forename: Sherif
authors.initials: S
authors.lastname: Elhanafi
authors.forename: Arleen M
authors.initials: AM
authors.lastname: Ortiz
authors.forename: Anita
authors.initials: A
authors.lastname: Yarlagadda
authors.forename: Cindy
authors.initials: C
authors.lastname: Tsai
authors.forename: Mohamed
authors.initials: M
authors.lastname: Eloliby
authors.forename: Indika
authors.initials: I
authors.lastname: Mallawaarachchi
authors.forename: Alok
authors.initials: A
authors.lastname: Dwivedi
authors.forename: Marc J
authors.initials: MJ
authors.lastname: Zuckerman
authors.forename: Mohamed O
authors.initials: MO
authors.lastname: Othman
mesh_terms: D000236:Adenoma / Q000175:diagnosis*; D000368:Aged; D003111:Colonic Polyps / Q000175:diagnosis*; D003113:Colonoscopy / Q000706:statistics & numerical data*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D003430:Cross-Sectional Studies; D055088:Early Detection of Cancer / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000706:statistics & numerical data*; D008875:Middle Aged; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D013781:Texas