CD4 and tuberculosis: Nonetheless, our finding that there is no hazard ratio modification with respect to baseline CD4 count is consistent with the randomised controlled trials, in which the reduction in tuberculosis incidence when initiating antiretroviral therapy at 200 to 350 cells/μl (HR 0.50, 95% CI 0.28 to 0.83) [51] was nearly identical to the reduction in tuberculosis incidence when initiating antiretroviral therapy above 350 cells/μl (IRR 0.51, 95% CI 0.28 to 0.91) [43].