Background:
There is conflicting evidence regarding the efficacy of SMS texts to promote TB medication adherence. Thus, we developed a mobile-assisted medication adherence support (Ma-MAS) intervention using the medical research council (MRC) framework based in a local context targeting audience needs and the effectiveness of this intervention evaluated in a sample of TB patients in Addis Ababa, Ethiopia.

Methods:
A parallel group randomized control trial design was used to evaluate the effectiveness of Ma-MAS intervention. In total, 186 adult TB patients (93 per group) were randomly assigned 1:1 to one of the two groups. Participants in the Ma-MAS group received daily SMS texts and weekly phone calls regarding their daily medication intake and reminders to attend clinic visits for 8 weeks. Participants in the control group did not receive SMS texts or phone calls but received the same routine standard care as the Ma-MAS group. The primary outcome was the proportion of adherence measured by urine tests for isoniazid (INH) metabolites at the end of the 4th and 8th week of follow-up period. Analysis of a multivariable binomial generalized linear model was employed to evaluate the effect of Ma-MAS at P value< 0.05.

Results:
Ma-MAS significantly improved adherence to TB medications by 15.25% (95%CI: 5.38, 25.12; P-value=0.0065) after 8 weeks of intervention compared to the standard care alone in the control group. At the end of the 8 weeks follow-up period, the predicted probability of adherence to TB medication in the Ma-MAS group was 86% (95%CI: 81, 93), and in the control group was 70% (95%CI: 61, 79). Ma-MAS also improved adherence to TB medication by 15.30% (95%CI: 6.68, 23.90; P-value=0.0022) after 4 weeks of intervention compared with the control group.

Conclusion:
Ma-MAS intervention based on information-motivation-behavioural skills model and behavioural change techniques is useful to improve adherence to TB medication.