title: Mixed contact methods to improve response to a postal questionnaire.
abstract: BACKGROUND
  Postal questionnaires remain an important method of collecting data in trials. However, a high non-response rate can lead to biases, which may undermine the validity of the study.
  
  
  OBJECTIVE
  To assess a simple method of trying to improve response rates in an occupational health trial evaluating an intervention to prevent hand dermatitis in nurses.
  
  
  METHODS
  The trial employed questionnaires at t = 0, t = 1 month and t = 12 months. The t = 1 month questionnaire was posted to study participants (student and intensive care nurses) together with a free postage reply envelope. After 2 weeks, an e-mail was sent to non-responders reinforcing the need for completed questionnaires to be returned. Two weeks later, non-responders were sent another hard copy of the questionnaire, along with an accompanying letter. Six weeks after posting the initial questionnaires, non-responders were sent an SMS text message or were telephoned to remind them to return the questionnaire.
  
  
  RESULTS
  The response rates for the 744 student nurses were 8% (no reminder), 27% (after first reminder), 22% (after second reminder) and 27% (after the third reminder), resulting in a response rate of 63%. The response rates for the 959 intensive care nurses were 9% (no reminder), 24% (after first reminder), 24% (after second reminder) and 31% (after third reminder), resulting in a final response rate of 63%.
  
  
  CONCLUSIONS
  We found that a series of regular reminders including a third, personalized reminder by SMS text or telephone had a positive impact on non-responders.
authors.affiliation: Occupational Health Service, Guy's & St Thomas' NHS Foundation Trust, London SE1 7EH, UK.
authors.forename: D
authors.initials: D
authors.lastname: Weston
authors.affiliation: Occupational Health Service, Guy's & St Thomas' NHS Foundation Trust, London SE1 7EH, UK.
authors.forename: V
authors.initials: V
authors.lastname: Parsons
authors.affiliation: MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton SO16 6YD, UK.
authors.forename: G
authors.initials: G
authors.lastname: Ntani
authors.affiliation: Faculty of Medicine, Imperial College London, London SW7 2AZ, UK.
authors.forename: L
authors.initials: L
authors.lastname: Rushton
authors.affiliation: Occupational Health Service, Guy's & St Thomas' NHS Foundation Trust, London SE1 7EH, UK.
authors.forename: I
authors.initials: I
authors.lastname: Madan
mesh_terms: D000328:Adult; D034742:Electronic Mail; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009726:Nurses; D011177:Postal Service / Q000379:methods*; D013338:Students, Nursing; D011795:Surveys and Questionnaires / Q000706:statistics & numerical data*; D013689:Telephone; D060145:Text Messaging; D006113:United Kingdom
keywords: Nurses; occupational health; responses rates; students; trials.