Comparison of methods for collection of DNA samples by mail in the Black Women's Health Study

Ann Epidemiol. 2004 Feb;14(2):117-22. doi: 10.1016/S1047-2797(03)00132-7.


Purpose: The authors compared approaches to participants and methods of collecting buccal cell samples by mail in the Black Women's Health Study, a follow-up study of geographically dispersed African-American women. Outcomes of interest were within group participation rates, yield of DNA, and PCR success.

Methods: Six hundred fifty six participants were randomized to four groups: Groups 1 and 2 used the cheek swab method and Groups 3 and 4 used the mouthwash swish method. Groups 1 and 3 were mailed collection kits together with consent forms, whereas Groups 2 and 4 were mailed a kit only after returning a signed consent.

Results: Participation rates were similar regardless of the method used for sample collection or mailing of the kits: samples were returned by 40% of Group 1, 37% of Group 2, 36% of Group 3, and 35% of Group 4. The median DNA yield was 3693 ng/sample for the swab method and 10,077 ng/sample for the mouthwash swish method (p<0.001). PCR analyses were successful in 98% of mouthwash samples and 94% of swab samples.

Conclusion: Because of its higher yield of DNA, the mouthwash swish method is preferable for collection of buccal cell samples by mail.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • African Americans / genetics*
  • African Americans / statistics & numerical data
  • Boston
  • DNA / analysis*
  • Data Collection / methods
  • Female
  • Humans
  • Middle Aged
  • Mouth Mucosa / cytology*
  • Mouthwashes
  • Neoplasms
  • Polymerase Chain Reaction
  • Postal Service
  • Specimen Handling / methods*
  • Surveys and Questionnaires
  • Women's Health*


  • Mouthwashes
  • DNA