TABLE 2

Receipt of Second Dose Influenza Vaccine by April 30, 2013, and by Day 42 Post Vaccination

% Receipt Second DoseDifference Versus Written Text Message ReminderDifference Versus Conventional Text Message Reminder
Absolute Difference, % (95% CI)RR (95% CI)Absolute Difference, % (95% CI)RR (95% CI)
Receipt by April 30
 Primary analytic sample
  Educational text message (n = 216)72.7% (157)P = .00315.6% (15.1–16.1)1.27 (1.11–1.47)6.0% (5.6–6.5)1.09 (0.96–1.23)
  Conventional text message (n = 225)66.7% (150)9.6% (9.1–10.0)1.17 (1.01–1.35)
  Written reminder only (n = 219)57.1% (125)
Receipt by day 42 post vaccination
 Primary analytic sample
  Educational text message (n = 216)43.5% (94)P < .00117.9% (17.5–18.4)1.70 (1.30–2.24)9.6% (9.1–10.0)1.28 (1.01–1.63)
  Conventional text message (n = 224)33.9% (76)8.4% (7.9–8.8)1.33 (0.99–1.77)
  Written reminder only (n = 219)25.6% (56)
  • Receipt by day 42 does not include participant who received the second dose too early and was not revaccinated. CI, 95% confidence interval; RR, relative rate.