ABSTRACT
INTRODUCTION: Short Message Service (SMS) appointment reminders may provide a wide-reaching, low cost approach to reducing operational inefficiencies and improving access to care. Previous studies indicate this modality may improve attendance rates, yet there is a need for large-scale, pragmatic studies that include unintended consequences and operational costs. METHODS: This pragmatic investigation was a before-after analysis that compared visit attendance outcomes among patients who opted into SMS appointment reminders with outcomes among those who declined over an 18-month evaluation period from March 25, 2013, to September 30, 2014. Eligibility in our integrated safety net health care system included age greater than 17, English or Spanish as a primary language, and a cell phone number in our scheduling system. RESULTS: 47,390 patients were invited by SMS to participate, of which 20,724 (43.7 percent) responded with 18,138 opting in (81.5 percent of respondents). Participants received SMS reminders for 77,783 scheduled visits; comparison group patients (N=72,757) were scheduled for 573,079 visits during the evaluation period. Intervention and comparison groups had, respectively, attendance rates of 72.8 percent versus 66.1 percent (p<0.001), cancellation rates of 13.2 percent versus 18.6 percent (p<0.001), and no show rates of 14.0 percent versus 15.3 percent. Patient satisfaction with text messaging ranged from 77 percent to 96 percent. Implementation challenges included a low rate of inaccurate reminders due to non-standard use of the scheduling system across clinical departments. DISCUSSION: SMS appointment reminders improve patient satisfaction and provide a low operating cost approach to reducing operational inefficiencies through improved attendance rates in an integrated safety net health care system.