Forty-two trials were included: 32 trials of health care provider support (5,323 participants) and ten trials of interventions for communication between health services and consumers (4,473 participants). Eleven of the trials were non-randomised. None of the trials were at low risk of bias for all criteria or reported an objective clinical outcome.
Trials of health care provider support reported 25 outcomes related to disease management; 11 showed statistically significant benefits. Two trials reported statistically significant reductions in correct diagnoses using mobile technology photos compared with a reference standard.
Text message reminders significantly increased appointment attendance by 6% compared with no reminder (RR 1.06, 95% CI 1.05 to 1.07; Ι²=86%; 10 trials), but there was no significant effect for cancelled appointments and no difference between text message and other types of reminder.
There was no evidence of publication bias.