TABLE 2—

Estimated Potential Annual Net Cost Savings if Text Message Reminders Were Implemented Throughout VHA With 15 500 Homeless Veterans: Providence, RI, 2013

	Savings From Avoiding Unused Appointments and Preventing Visits			Costs of Text-Messaging System, From Health System and Patient Perspectives
Variable	Saved Utilization per Person per Yeara	Average Unit Cost of Service, $	Savings for 15 500 Veterans,a in Millions of $	Texts Sent or Received per Patient per Year	Average Cost per Text Message Sent or Received, $	Cost for 15 500 Veterans, $
Savings factor
Patient-cancelled appointments (and not refilled) avoidedb	2.08 (−1.95, 6.11)	198	6.38 (−5.98, 18.75)
Patient no-shows avoidedc	1.95 (0.00, 8.65)	198	5.98 (0.00, 26.53)
Patient ED visits avoided	3.25 (0.72, 5.79)	791	39.85 (8.77, 70.93)
Total savings			52.21 (2.78, 116.21)
Costs factor
Cost to health system of text messaging				137	0.12	254 820
Cost to veterans of receiving text messages				137	0.10	212 350
Total costs						467 170
Net savings, $, in millions			51.75 (2.31, 115.74)

Note. ED = emergency department; VHA = Veterans Health Administration.

^aRanges reflect the 95% confidence intervals (CIs) around the point estimates for mean reduction in service.

^bPatient cancellations only count the 40% that are estimated not to be refilled with another patient.

^cRange originally included a negative number (−4.75). Because it was highly unlikely the intervention would increase no-shows, the negative bound was set to zero.