title: Randomized trial of leaving messages on telephone answering machines for control recruitment in an epidemiologic study.
abstract: To determine whether leaving messages on answering machines would aid control recruitment via random-digit telephone dialing, a randomized trial was conducted during 1992-1994 involving 1,323 western Washington households with answering machines. For the experimental group, a message was left informing them about the study and promising a call-back; for the control group, no message was left. Leaving a message increased the response rate by about 20 percentage points (p = 0.002). More households were successfully screened for eligible controls, and individuals found eligible were more likely to participate. Leaving a message can help to improve response rates in telephone surveys.
authors.affiliation: Department of Epidemiology, University of Washington, Seattle 98195-7236, USA.
authors.forename: T D
authors.initials: TD
authors.lastname: Koepsell
authors.forename: V
authors.initials: V
authors.lastname: McGuire
authors.forename: W T
authors.initials: WT
authors.lastname: Longstreth
authors.forename: L M
authors.initials: LM
authors.lastname: Nelson
authors.forename: G
authors.initials: G
authors.lastname: van Belle
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007407:Interviews as Topic / Q000379:methods; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D013689:Telephone / Q000706:statistics & numerical data; D014861:Washington