Using short message service text reminders to reduce 'did not attend' rates in sexual health and HIV appointment clinics.

'Did not attend' and cancellation rates were compared for two 12-month periods before (2009) and after (2012/2013) the introduction of routine short message service text reminders being sent to patients who have pre-booked appointments. After the introduction of short message service text appointment reminders, the overall 'did not attend' rates fell by 4% from 28% to 24% (p < 0.005) and by 10% from 28% to 18% (p < 0.05) for male sexual health appointments. There was no significant change in the HIV clinic 'did not attend' rates. In the same periods, the cancellation rates increased 4% overall (from 62% to 66%) and by 17% (from 55% to 72%) for female sexual health clinics (p < 0.005). These results suggest that routine text reminders increase clinic attendance rates by reminding patients to attend and prompting them to cancel if they cannot come.