Clinical Interest and Economic Impact of Preoperative SMS Reminders before Ambulatory Surgery: A Propensity Score Analysis.

Patient contact by telephone the day before ambulatory surgery is considered as a best practice. The Short Message Service (SMS) could be a suitable alternative. The objective of this prospective study was to evaluate the interest of preoperative instruction (PI) reminders by SMS compared to telephone calls. This was a prospective single center before-and-after study. Patients scheduled in ambulatory surgery were included during 2 consecutive periods of 10 weeks. The "Call" group received a telephone call for preoperative instructions (PI) and the "SMS" group received an automated protocol SMS reminder. The primary endpoint was patient compliance with PI and time of convocation. The two populations were compared with a non-inferiority hypothesis and the impact of the contact modality on compliance with the PI was assessed using a propensity score. The analysis concerned 301 patients in the Call group and 298 in the SMS group. The absence of dysfunction was observed in 75% of patients in the SMS group compared with 61% in the Call group (Risk difference: 14% [95%CI: 7-21]). The use of SMS was associated with a significant improvement in compliance with the PI (Odds ratio: 1.90 [1.48-2.42]; p < 0.0001). Patient satisfaction was similar regardless of the method of PI reminders. The automation of preoperative SMS reminders is associated with a better respect of the PI compared to the conventional calling method. This PI reminder method satisfies the majority of patients and may have a favorable financial impact.