title: The effect of advance telephone prompting in a survey of general dental practitioners in scotland: a randomised controlled trial.
abstract: OBJECTIVE
  Evaluation of advance telephone prompting on the response rate to a postal, self-completed questionnaire. To provide an estimate of the cost of such a strategy.
  
  
  METHODS
  A sample of 315 GDPs was randomly selected from a randomised database of GDPs practicing in Scotland. 157 GDPs were randomly allocated to receive an advance telephone prompt, via the practice receptionist; 158 were allocated to a control group. Four days after prompting all trial participants were mailed identical questionnaires, cover letter and postage paid return envelope.
  
  
  RESULTS
  Response rates: 53%--advance telephone prompt group and 40%--control group. The effect size, 13%, was found to be statistically significant, p = 0.026. Total estimated strategy costs: 74.00 pounds sterling. The incremental cost was estimated to be 4.93 pounds sterling for each additional response.
  
  
  CONCLUSIONS
  Advance telephone prompting of GDP's, via the practice receptionist, statistically significantly improves the response rate to a postal self-completed questionnaire. This is estimated to be a cost effective strategy for improving response rates to postal questionnaires.
authors.affiliation: Orthodontic Department, Victoria Hospital, Hayfield Road, Kirkcaldy. John.Hoayun@faht.scot.nhs.uk
authors.forename: J
authors.initials: J
authors.lastname: Ho-A-Yun
authors.forename: F
authors.initials: F
authors.lastname: Crawford
authors.forename: J
authors.initials: J
authors.lastname: Newton
authors.forename: J
authors.initials: J
authors.lastname: Clarkson
mesh_terms: D005260:Female; D005792:General Practice, Dental / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D017010:Reminder Systems / Q000191:economics / Q000706:statistics & numerical data*; D012606:Scotland; D011795:Surveys and Questionnaires; D013689:Telephone