We aimed to develop a decision aid that estimates whether treatment of latent tuberculosis infection (LTBI) is likely to have a net gain in quality-adjusted life-years for an individual. A Markov model was developed which incorporated personalised estimates for risk of tuberculosis (TB) reactivation, TB death, quality-of-life impairments and treatment side-effects. The net effect of LTBI treatment was quantified in terms of quality-adjusted life-years gained or lost. Analyses were conducted for a representative set of hypothetical patients. LTBI treatment was estimated to be beneficial when the annual risk of TB reactivation exceeded 13/100 000 to 93/100 000 for females aged 10–75 years and 15/100 000 to 119/100 000 for males aged 10–75 years; the numbers needed to tr...