title: Effect of survey instrument on participation in a follow-up study: a randomization study of a mailed questionnaire versus a computer-assisted telephone interview.
abstract: BACKGROUND
  Many epidemiological and public health surveys report increasing difficulty obtaining high participation rates. We conducted a pilot follow-up study to determine whether a mailed or telephone survey would better facilitate data collection in a subset of respondents to an earlier telephone survey conducted as part of the National Birth Defects Prevention Study.
  
  
  METHODS
  We randomly assigned 392 eligible mothers to receive a self-administered, mailed questionnaire (MQ) or a computer-assisted telephone interview (CATI) using similar recruitment protocols. If mothers gave permission to contact the fathers, fathers were recruited to complete the same instrument (MQ or CATI) as mothers.
  
  
  RESULTS
  Mothers contacted for the MQ, within all demographic strata examined, were more likely to participate than those contacted for the CATI (86.6% vs. 70.6%). The median response time for mothers completing the MQ was 17 days, compared to 29 days for mothers completing the CATI. Mothers completing the MQ also required fewer reminder calls or letters to finish participation versus those assigned to the CATI (median 3 versus 6), though they were less likely to give permission to contact the father (75.0% vs. 85.8%). Fathers contacted for the MQ, however, had higher participation compared to fathers contacted for the CATI (85.2% vs. 54.5%). Fathers recruited to the MQ also had a shorter response time (median 17 days) and required fewer reminder calls and letters (median 3 reminders) than those completing the CATI (medians 28 days and 6 reminders).
  
  
  CONCLUSIONS
  We concluded that offering a MQ substantially improved participation rates and reduced recruitment effort compared to a CATI in this study. While a CATI has the advantage of being able to clarify answers to complex questions or eligibility requirements, our experience suggests that a MQ might be a good survey option for some studies.
authors: Department of Epidemiology, College of Public Health, The University of Iowa, Iowa City, IA 52242, USA. crocheleau@cdc.gov
authors: Carissa M
authors: CM
authors: Rocheleau
authors: Paul A
authors: PA
authors: Romitti
authors: Stacey Hockett
authors: SH
authors: Sherlock
authors: Wayne T
authors: WT
authors: Sanderson
authors: Erin M
authors: EM
authors: Bell
authors: Charlotte
authors: C
authors: Druschel
mesh_terms: D000328:Adult; D003256:Community Participation / Q000706:statistics & numerical data*; D003201:Computers; D003625:Data Collection / Q000295:instrumentation*; D005220:Fathers / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009035:Mothers / Q000706:statistics & numerical data*; D010865:Pilot Projects; D011177:Postal Service; D011795:Surveys and Questionnaires; D013689:Telephone; D055815:Young Adult