METHOD: A mixed methods approach will be used. Qualitative part: Design: focus group discussions (FGDs) will be conducted.

SETTING: Hospital/NGOs in Terengganu, Malaysia.

PARTICIPANTS: Three FGDs will be conducted with male and female HIV/AIDS patients, and one group of local community leaders. One FGD will be conducted for each group. Three in-depth interviews (IDIs) will be conducted with patients who had HIV/AIDS, of which one will be female. Quantitative part: Design: a cluster randomized clinical trial with 384 HIV/AIDS patients in Terengganu, Malaysia.

INTERVENTION: Mobile SMS counselling intervention for patients concerning the prevention of HIV/AIDS.

RESULTS: The main outcomes of this study will be the differences in knowledge, attitude, and practices of patients concerning the prevention of HIV/AIDS between the baseline and immediate follow-up after the intervention, and after 3 months.

CONCLUSIONS: The mobile based SMS counselling intervention developed will be effective in improving the knowledge, attitude, and practices of patients concerning HIV/AIDS prevention in Terengganu, Malaysia.