title: Factors influencing enrollment of African Americans in the Look AHEAD trial.
abstract: BACKGROUND
  Many factors have been identified that influence the recruitment of African Americans into clinical trials; however, the influence of eligibility criteria may not be widely appreciated. We used the experience from the Look AHEAD (Action for Health in Diabetes) trial screening process to examine the differential impact eligibility criteria had on the enrollment of African Americans compared to other volunteers.
  
  
  METHODS
  Look AHEAD is a large randomized clinical trial to examine whether assignment to an intensive lifestyle intervention designed to produce and maintain weight loss reduces the long-term risk of major cardiovascular events in adults with type 2 diabetes. Differences in the screening, eligibility, and enrollment rates between African Americans and members of other racial/ethnic groups were examined to identify possible reasons.
  
  
  RESULTS
  Look AHEAD screened 28,735 individuals for enrollment, including 6226 (21.7%) who were self-identified African Americans. Of these volunteers, 12.9% of the African Americans compared to 19.3% of all other screenees ultimately enrolled (p < 0.001). African Americans no more often than others were lost to follow-up or refused to attend clinic visits to establish eligibility. Furthermore, the enrollment rates of individuals with histories of cardiovascular disease and diabetes therapy did not markedly differ between the ethnic groups. Higher prevalence of adverse levels of blood pressure, heart rate, HbA1c, and serum creatinine among African American screenees accounted for the greater proportions excluded (all p < 0.001).
  
  
  CONCLUSIONS
  Compared to non-African Americans, African American were more often ineligible for the Look AHEAD trial due to comorbid conditions. Monitoring trial eligibility criteria for differential impact, and modifying them when appropriate, may ensure greater enrollment yields.
authors: Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA. Dmount@wfubmc.edu
authors: David L
authors: DL
authors: Mount
authors: Cralen
authors: C
authors: Davis
authors: Betty
authors: B
authors: Kennedy
authors: Susan
authors: S
authors: Raatz
authors: Kathy
authors: K
authors: Dotson
authors: Tiffany L
authors: TL
authors: Gary-Webb
authors: Sheikilya
authors: S
authors: Thomas
authors: Karen C
authors: KC
authors: Johnson
authors: Mark A
authors: MA
authors: Espeland
mesh_terms: D001741:Black or African American / Q000706:statistics & numerical data*; D000368:Aged; D002318:Cardiovascular Diseases / Q000209:etiology / Q000517:prevention & control; D003924:Diabetes Mellitus, Type 2 / Q000150:complications; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D016032:Randomized Controlled Trials as Topic / Q000592:standards*