title: Impact of physician reminders on the use of influenza vaccinations: a randomized trial.
abstract: OBJECTIVE
  To analyze the impact of mailed physician reminders to immunize their patients.
  
  
  METHODS
  Randomized trial involving Washington State physiatrists participating in the Medicare program. In 1997, all physiatrists in the state were separated into solo or group practice. Solo physicians and group practices were then separately randomized to receive 4 monthly reminders to have their patients immunized. In 1998, the intervention and control groups were switched.
  
  
  METHODS
  The state of Washington.
  
  
  METHODS
  A total of 4300 Medicare outpatients seen in Washington State in 1997 and 4025 patients in 1998.
  
  
  METHODS
  Repeated mailer.
  
  
  METHODS
  By using multivariate analysis, Medicare billing data was analyzed to determine the impact of the physician reminders on influenza vaccination rates.
  
  
  RESULTS
  Among solo practitioners, patients whose physiatrist received the reminder letters in 1998 were 34% more likely (adjusted relative risk [RR] = 1.34; 95% confidence interval [CI],.96-1.88) to have a vaccination billing. Among group practitioners, those patients whose physiatrist received the reminder letters in 1997 were 26% more likely (RR = 1.26; 95% CI,.98-1.60) to have a vaccination billing. These differences, however, were not statistically significant. The adjusted RRs for the remaining intervention groups, solo practitioners in 1997 (RR =.89; 95% CI,.63-1.26), and group practitioners in 1998 (RR = 1.00; 95% CI,.73-1.36), revealed no increase in vaccination billings for patients whose physiatrist received the intervention.
  
  
  CONCLUSIONS
  Repeated physician reminders did not increase the vaccination rate of Washington State Medicare patients who were seen by physiatrists in 1997 and 1998. These results were consistent whether the physiatrists were in solo or group practice. Other methods should be considered to improve the primary care delivered to this Medicare population.
authors.affiliation: Division of Clinical Standards and Quality, Health Care Financing Administration, MS-RX 42, Region 10, 2201 6th Avenue, Seattle, WA 98121, USA. leighton@u.washington.edu
authors.forename: Leighton
authors.initials: L
authors.lastname: Chan
authors.forename: Richard F
authors.initials: RF
authors.lastname: MacLehose
authors.forename: Peter M
authors.initials: PM
authors.lastname: Houck
mesh_terms: D000368:Aged; D018592:Cross-Over Studies; D005260:Female; D006123:Group Practice; D006801:Humans; D007115:Immunization Schedule; D007252:Influenza Vaccines; D008297:Male; D006278:Medicare; D010810:Physical and Rehabilitation Medicine; D011177:Postal Service; D011320:Primary Health Care / Q000379:methods; D011331:Private Practice; D017010:Reminder Systems; D014861:Washington
chemical_list: D007252:Influenza Vaccines