Table 2.
Primary and secondary study outcomes—comparison of mortality rates between study phases
| ART enrollees | Deaths (n)a | Rate/100PYb | Crude HRc | (95% CI) | p | AHRcd | (95% CI) | p | |
|---|---|---|---|---|---|---|---|---|---|
| Primary outcome: 6-month ART mortality in SOC versus EC+X phase | |||||||||
| SOC | 8980 | 461 | 11.4 | 1.00 | – | – | 1.00 | – | – |
| EC+X | 4215 | 121 | 6.3 | 0.58 | (0.48–0.71) | < 0.001 | 0.77 | (0.61–0.97) | 0.029 |
| Secondary outcomes: 12-month ART mortality in SOC versus EC+X phase | |||||||||
| SOC | 8980 | 551 | 7.3 | 1.00 | – | – | 1.00 | – | – |
| EC+X | 4215 | 137 | 4.6 | 0.58 | (0.48–0.70) | < 0.001 | 0.76 | (0.61–0.95) | 0.014 |
| 6-month ART mortality in EC versus EC+X phasee | |||||||||
| EC | 1768 | 54 | 6.5 | 1.00 | 1.00 | ||||
| EC+X | 4215 | 121 | 6.3 | 1.07 | (0.62–1.84) | 0.800 | 1.13 | (0.63–2.03) | 0.690 |
Abbreviations: SOC standard of care phase, EC enhanced care phase, EC+X enhanced care plus Xpert phase, PY person-years, HR hazard ratio, AHR adjusted hazard ratio, CI confidence interval, XPRES Xpert Package Rollout Evaluation using a Stepped-Wedge design
aRepresents deaths observed among all ART enrollees by the time point specified
bRepresents unadjusted 6- and 12-month ART mortality rates among all ART enrollees in each phase of the study. For mortality rates among ART enrollees included in the adjusted analyses, see Additional file 6
cAll Cox proportional hazards regression models included a random effect for clinic
dAdjusted for the following characteristics at ART initiation: age, sex, pregnancy status, weight, CD4 count, hemoglobin, and ART regimen. Adjusted analysis comparing SOC versus EC+X mortality rates included 7184 SOC enrollees with 350 deaths within 6 months and 424 deaths within 12 months, and 3861 EC+X enrollees with 93 deaths within 6 months and 108 deaths within 12 months
eAnalysis restricted to randomized stepped-wedge portion of the trial, fitting a Cox proportional hazards regression model to the data with the underlying time frame beginning August 2012 (the start of EC enrollment), and including a fixed effect for monthly changes in mortality rates during the first 6 months of ART. Adjusted analysis comparing EC versus EC+X mortality rates included 1653 EC enrollees with 43 deaths within 6 months and 3861 EC+X enrollees with 93 deaths within 6 months