The alpha coded testing (ACT) study offers free and confidential testing for alpha-1 antitrypsin deficiency (AATD) and includes surveys to provide data to study the psychosocial correlates of genetic testing. The purpose of the current study is to better understand reasons why some individuals complete genetic testing while others do not. Survey measures were compared between participants who requested and returned a genetic test for AATD (n=703), and a random sample of individuals who requested a test kit, but did not return it within 3 months of their request (n=83). Increasing decile of age (odds ratio [OR]=0.74 [95% confidence interval=0.60-0.82]) and fingerstick fear (OR=0.74 [0.60-0.93]) were associated with a decreased likelihood of returning the test, while assurance of confidentiality was associated with an increased likelihood (OR=1.26 [1.01-1.57]) of returning the genetic test. General anxiety as measured by the Beck Anxiety Inventory, family functioning as measured by the general functioning subscale of the Family Assessment Device, and stress induced by genetic testing as measured by the Impact of Events Scale did not significantly differ between responder groups (p=not significant). Results of this study help characterize factors driving genetic testing in AATD and may offer insight into population responses with other genetic tests. © Copyright 2008, Mary Ann Liebert, Inc.