Evidence-based recommendations of preventive chemotherapy against latent infection with Mycobacterium tuberculosis in adults
| Evidence | Evidence level | Isoniazid alone | Rifampicin-based treatment |
| Randomised trials | A | 12 months 33, 125 | 3 months of rifampicin plus isoniazid 126 |
| Nonrandomised trials | C | 9 months 127 | 4 months of rifampicin 127 |