Text Messages Sent to Household Tuberculosis Contacts in Kampala, Uganda: Process Evaluation

Area of Science:

• Public Health
• Health Communication
• Implementation Science

Background:

• Text messaging (short message service, SMS) effectiveness for health outcomes is inconsistent.
• Implementation fidelity is a key factor potentially explaining variable study results.

Purpose of the Study:

• To determine the fidelity of a one-time SMS intervention for promoting tuberculosis evaluation service uptake.
• To assess the reach and retention of SMS messages among household contacts of tuberculosis patients.

Main Methods:

• A process evaluation was nested within a randomized controlled trial in Kampala, Uganda.
• Household contacts confirmed SMS receipt via reply SMS or telephone follow-up.
• Participants were considered lost to follow-up after 3 unsuccessful telephone contact attempts.

Main Results:

• Only 67% of participants confirmed SMS receipt, with 22% via reply SMS and 45% via telephone.
• The cumulative likelihood of an SMS reaching its target, being read, and retained was 19%.
• No significant demographic differences were found between those who did and did not report receiving the SMS.

Conclusions:

• The fidelity of the one-time SMS intervention for tuberculosis contact investigation was extremely low.
• Detailed process evaluation is crucial for uncovering implementation fidelity issues.
• Systematic process monitoring and reporting of implementation fidelity are recommended for mobile health interventions.