title: Prenotification but not envelope teaser increased response rates in a bulimia nervosa mental health literacy survey: A randomized controlled trial.
abstract: OBJECTIVE
  Understanding attitudes to mental health issues can inform public health interventions. However, low response rates may contribute to nonresponse bias. In a randomized controlled trial we examined the effect of sending a prenotification postcard before the questionnaire and the placement of a short message on the survey envelope (teaser) on response rates to a mailed questionnaire about bulimia nervosa "mental health literacy".
  
  
  METHODS
  Questionnaires were mailed to 3,010 adults (50.6% female and 49.4% male) aged 18-65 years. In a 2 (pre-notification-present; absent) by 2 (teaser-present; absent) design, questionnaire recipients were randomly allocated to the experimental strategies. Outcomes considered were response rate, response time, and cost.
  
  
  RESULTS
  The overall response rate was 22.0%. Significant main effects showed higher response rates for the use of prenotification (present = 23.6%; absent = 20.3%), among female participants, and older participants. A significant interaction of teaser by gender indicated lower response rates for men who received the teaser but not for women. Older participants returned the questionnaire more promptly than younger participants. Females-but not males-who received the teaser were slower to return the questionnaire. Higher response rates for participants receiving the postcard compensated for increased costs, particularly for males and older participants.
  
  
  CONCLUSIONS
  Response rates to a mental health postal survey can be increased through the use of prenotification.
authors.affiliation: School of Psychological Science, La Trobe University, Kingsbury Drive, Melbourne, VIC 3086, Australia. Electronic address: s.mclean@latrobe.edu.au.
authors.forename: Siân A
authors.initials: SA
authors.lastname: McLean
authors.affiliation: School of Psychological Science, La Trobe University, Kingsbury Drive, Melbourne, VIC 3086, Australia.
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Paxton
authors.affiliation: School of Psychological Science, La Trobe University, Kingsbury Drive, Melbourne, VIC 3086, Australia.
authors.forename: Robin
authors.initials: R
authors.lastname: Massey
authors.affiliation: Research School of Psychology, The Australian National University, Barry Drive, Canberra, ACT 0200, Australia; Centre for Rural and Remote Mental Health, University of Newcastle, University Drive, Orange, NSW 2308, Australia.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Mond
authors.affiliation: Australian Demographic & Social Research Institute, The Australian National University, Barry Drive, Canberra, ACT 0200, Australia.
authors.forename: Bryan
authors.initials: B
authors.lastname: Rodgers
authors.affiliation: Centre for Health Research, School of Medicine, University of Western Sydney, Narellan Road, Sydney, NSW 2751, Australia; School of Medicine, James Cook University, 1 James Cook Drive, Townsville, QLD 4811, Australia.
authors.forename: Phillipa J
authors.initials: PJ
authors.lastname: Hay
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D052018:Bulimia Nervosa / Q000523:psychology*; D005260:Female; D057220:Health Literacy; D006801:Humans; D008297:Male; D008875:Middle Aged; D011177:Postal Service / Q000379:methods*; D017010:Reminder Systems; D012107:Research Design; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Bulimia nervosa; Demographic groups; Nonresponse bias; Prenotification; Questionnaire response rates; Teaser