title: Social networking versus facebook advertising to recruit survey respondents: a quasi-experimental study.
abstract: BACKGROUND
  Increasingly, social contact and knowledge of other people's attitudes and behavior are mediated by online social media such as Facebook. The main research to which this recruitment study pertains investigates the influence of parents on adolescent alcohol consumption. Given the pervasiveness of online social media use, Facebook may be an effective means of recruitment and intervention delivery.
  
  
  OBJECTIVE
  The objective of the study was to determine the efficacy of study recruitment via social networks versus paid advertising on Facebook.
  
  
  METHODS
  We conducted a quasi-experimental sequential trial with response rate as the outcome, and estimates of cost-effectiveness. The target population was parents of 13-17 year old children attending high schools in the Hunter region of New South Wales, Australia. Recruitment occurred via: method (1) social recruitment using Facebook, email-based, social networks, and media coverage followed by method (2) Facebook advertising.
  
  
  RESULTS
  Using a range of online and other social network approaches only: method (1) 74 parents were recruited to complete a survey over eight months, costing AUD58.70 per completed survey. After Facebook advertising: method (2) 204 parents completed the survey over four weeks, costing AUD5.94 per completed survey. Participants were representative of the parents recruited from the region's schools using standard mail and email.
  
  
  CONCLUSIONS
  Facebook advertising is a cost-effective means of recruiting parents, a group difficult to reach by other methods.
authors.affiliation: School of Medicine and Public Health, Faculty of Health and Medicine, University of Newcastle, Callaghan, Australia. Conor.Gilligan@newcastle.edu.au.
authors.forename: Conor
authors.identifier: http://orcid.org/0000-0001-5493-4309
authors.initials: C
authors.lastname: Gilligan
authors.forename: Kypros
authors.identifier: http://orcid.org/0000-0002-9657-9904
authors.initials: K
authors.lastname: Kypri
authors.forename: Jesse
authors.identifier: http://orcid.org/0000-0002-8947-491X
authors.initials: J
authors.lastname: Bourke
keywords: Facebook; Facebook advertising; recruitment