title: Text messaging reminders for influenza vaccine in primary care: a cluster randomised controlled trial (TXT4FLUJAB).
abstract: OBJECTIVE
  (1) To develop methods for conducting cluster randomised trials of text messaging interventions utilising routine electronic health records at low cost; (2) to assess the effectiveness of text messaging influenza vaccine reminders in increasing vaccine uptake in patients with chronic conditions.
  
  
  METHODS
  Cluster randomised trial with general practices as clusters.
  
  
  METHODS
  English primary care.
  
  
  METHODS
  156 general practices, who used text messaging software, who had not previously used text message influenza vaccination reminders. Eligible patients were aged 18-64 in 'at-risk' groups.
  
  
  METHODS
  Practices were randomly allocated to either an intervention or standard care arm in the 2013 influenza season (September to December). Practices in the intervention arm were asked to send a text message influenza vaccination reminder to their at-risk patients under 65. Practices in the standard care arm were asked to continue their influenza campaign as planned.
  
  
  METHODS
  Practices were not blinded. Analysis was performed blinded to practice allocation.
  
  
  METHODS
  Practice-level influenza vaccine uptake among at-risk patients aged 18-64 years.
  
  
  RESULTS
  77 practices were randomised to the intervention group (76 analysed, n at-risk patients=51,121), 79 to the standard care group (79 analysed, n at-risk patients=51,136). The text message increased absolute vaccine uptake by 2.62% (95% CI -0.09% to 5.33%), p=0.058, though this could have been due to chance. Within intervention clusters, a median 21.0% (IQR 10.2% to 47.0%) of eligible patients were sent a text message. The number needed to treat was 7.0 (95% CI -0.29 to 14.3).
  
  
  CONCLUSIONS
  Patient follow-up using routine electronic health records is a low cost method of conducting cluster randomised trials. Text messaging reminders are likely to result in modest improvements in influenza vaccine uptake, but levels of patients being texted need to markedly increase if text messaging reminders are to have much effect.
  
  
  BACKGROUND
  ISRCTN48840025.
authors.affiliation: London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Emily
authors.initials: E
authors.lastname: Herrett
authors.affiliation: London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Williamson
authors.affiliation: Health eResearch Centre, Farr Institute, University of Manchester, Manchester, UK Faculty of Sciences, Division of Pharmacoepidemiology and Clinical Pharmacology, Department of Pharmaceutical Sciences, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Tjeerd
authors.initials: T
authors.lastname: van Staa
authors.affiliation: London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: Ranopa
authors.affiliation: London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Caroline
authors.initials: C
authors.lastname: Free
authors.affiliation: Health and Wellbeing Directorate, Public health England, Wellington House, London, UK.
authors.forename: Tim
authors.initials: T
authors.lastname: Chadborn
authors.affiliation: London School of Hygiene and Tropical Medicine, London, UK Department of Primary Care Health Sciences, Centre for Evidence Based Medicine, University of Oxford, Radcliffe Observatory Quarter, Oxford, UK.
authors.forename: Ben
authors.initials: B
authors.lastname: Goldacre
authors.affiliation: London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Liam
authors.initials: L
authors.lastname: Smeeth
mesh_terms: D000293:Adolescent; D000328:Adult; D057286:Electronic Health Records; D005260:Female; D058006:General Practice; D006801:Humans; D017589:Immunization Programs / Q000379:methods; D007252:Influenza Vaccines / Q000627:therapeutic use*; D007251:Influenza, Human / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D011320:Primary Health Care / Q000379:methods*; D017010:Reminder Systems; D060145:Text Messaging; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines
keywords: PUBLIC HEALTH