CD4 and VL at switch to second-line for first-line failure in patients not receiving CD4 or VL count monitoring (CDM).

*p = 0.84 adjusted for whether whether enrolled in second-line studies (p[9]; see Results.**ROC area under the curve = 0.90 (95% CI 0.83–0.98) in 117 patients enrolled in second-line studies, vs 0.93 (95% CI 0.86–0.99) in 64 patients not enrolled in second-line studies.†66/207 (32%) also had WHO 3 events in the month prior to switch (of which 37 were oral candida and 19 were weight loss >10%)‡retrospectively on stored plasmaNote: ROC = receiver operating characteristic, see Figure 2. Two switches 46 weeks after ART initiation: all others ≥52 weeks.