To assess delays in response to patient secure e-mail messages in primary care.
Secure electronic messages are initiated by primary care patients. Timely response is necessary for patient safety and quality.
A database of secure messages.
A random sample of 353 secure electronic messages initiated by primary care patients treated in 4 clinics.
Message not opened after 12 hours or messages not responded to after 36 hours.
A total of 8.5% of electronic messages were not opened within 12 hours, and 17.6% did not receive a response in 36 hours. Clinic location, being a clinic employee, and patient sex were not related to delays. Patients older than 50 years were more likely to receive a delayed response (25.7% delayed, P = .013). The risk of both kinds of delays was higher on weekends (P < .001 for both).
The e-mail message system resulted in high rates of delayed response. Delays were concentrated on weekends (Friday-Sunday). Reducing delayed responses may require automatic rerouting of messages to message centers staffed 24–7 or other mechanisms to manage this after-hours work flow.