Abstract: Nine trials, including 4654 participants, met our inclusion criteria. Five trials evaluated appointment reminders for people on treatment for active TB, two for people on prophylaxis for latent TB, and four for people undergoing TB screening using skin tests. We classified the interventions into 'pre-appointment' reminders (telephone calls or letters prior to a scheduled appointment) or 'default' reminders (telephone calls, letters, or home visits to people who had missed an appointment). For people being treated for active TB, clinic attendance and TB treatment completion were higher in people receiving pre-appointment reminder phone-calls (clinic attendance: 66% versus 50%; RR 1.32, 95% CI 1.10 to 1.59, one trial (USA), 615 participants, low quality evidence; TB treatment completion: 100% versus 88%; RR 1.14, 95% CI 1.02 to 1.27, one trial (Thailand), 92 participants, low quality evidence). Clinic attendance and TB treatment completion were also higher with default reminders (letters or home visits) (clinic attendance: 52% versus 10%; RR 5.04, 95% CI 1.61 to 15.78, one trial (India), 52 participants, low quality evidence; treatment completion: RR 1.17, 95% CI 1.11 to 1.24, two trials (Iraq and India), 680 participants, moderate quality evidence). For people on TB prophylaxis, clinic attendance was higher with a policy of pre-appointment phone-calls (63% versus 48%; RR 1.30, 95% CI 1.07 to 1.59, one trial (USA), 536 participants); and attendance at the final clinic was higher with regular three-monthly phone-calls or nurse visits (93% versus 65%, one trial (Spain), 318 participants). For people undergoing screening for TB, three trials of pre-appointment phone-calls found little or no effect on the proportion of people returning to clinic for the result of their skin test (three trials, 1189 participants, low quality evidence), and two trials found little or no effect with take home reminder cards (two trials, 711 participants). All four trials were conducted among healthy volunteers in the USA. Policies of sending reminders to people pre-appointment, and contacting people who miss appointments, seem sensible additions to any TB programme, and the limited evidence available suggests they have small but potentially important benefits. Future studies of modern technologies such as short message service (SMS) reminders would be useful, particularly in low-resource settings.

Plain-language summary: This Cochrane Review summarizes trials evaluating the effects of reminder systems on attendance at tuberculosis (TB) clinics and completion of TB treatment. After searching for relevant trials up to 29 August 2014, we included nine trials, including 4654 people. What are reminder systems and how might they help? Effective treatment for TB requires people to take multiple drugs daily for at least six months. Consequently, once they start to feel well again, some patients stop attending clinics and stop taking their medication which can lead to the illness returning and the development of drug resistance. One strategy the World Health Organization recommends is that an appointed person (a health worker or volunteer) watches the person take their medication everyday (called direct observation). Other strategies include reminder systems to prompt patients to attend for appointments on time, or to re-engage people who have missed or defaulted on a scheduled appointment. These prompts may be in the form of telephone calls or letters before the next scheduled appointment ("pre-appointment reminders"), or phone calls, letters, or home visits after a missed appointment ("default reminders"). What the research says: For people being treated for active TB: - More people attended the clinic and completed TB treatment with pre-appointment reminder phone-calls (low quality evidence). - More people attended the clinic and completed TB treatment with a policy of default reminders (low and moderate quality evidence respectively). For people on TB prophylaxis: - More people attended the clinic with pre-appointment phone-calls, and the number attending the final clinic was higher with three-monthly phone-calls or nurse home visits. For people undergoing screening for TB: - Similar numbers of people attended clinic for skin test reading with and without pre-appointment phone-calls (low quality evidence). - Similar numbers of people attended clinic for skin test reading with and without take home reminder cards.