Skip to main content
. Author manuscript; available in PMC: 2021 Dec 28.
Published in final edited form as: J Clin Epidemiol. 2021 Sep 3;140:101–110. doi: 10.1016/j.jclinepi.2021.09.001

Table 2:

Percentage with pre-ART CD4 testing before and after national Treat-All policy adoption by country.

Lesotho Malawi Mozambique South Africa Zambia Zimbabwe

Patients 1,882 (100%) 13,876 (100%) 10,534 (100%) 23,817 (100%) 178,465 (100%) 7,254 (100%)
 before Treat-All 816 (43%) 7,260 (52%) 4,958 (47%) 10,777 (45%) 76,349 (43%) 3,868 (53%)
 after Treat-All 1,066 (57%) 6,616 (48%) 5,576 (53%) 13,040 (55%) 102,116 (57%) 3,386 (47%)

Risk difference at threshold* −8.6 −21.4 −8.8 1.2 2.7 0.2
 (95% CI) (−20.9, 3.7) (−26.8, −16.0) (−14.9, −2.8) (−1.3, 3.7) (0.4, 5.1) (−7.0, 7.5)
 p-value 0.171 <0.001 0.004 0.345 0.024 0.949
 IK bandwidth (days) 238 123 238 347 105 241
 patients within bandwidth 751 3,189 3,790 12,923 27,298 2,771
Treatment Effect Derivative −0.101 −0.056 −0.048 −0.010 −0.066 −0.025
 (95% CI) (−0.198, −0.004) (−0.130, 0.019) (−0.091, −0.004) (−0.021, 0.003) (−0.104, −0.028) (−0.078, 0.029)
 p-value 0.041 0.145 0.004 0.128 0.001 0.368

Predicted outcomes at threshold
 just before Treat-All 70.5 29.0 66.5 85.3 39.5 34.0
  (95% CI) (60.5, 80.4) (24.0, 33.9) (62.6, 70.5) (83.5, 87.1) (37.8, 41.2) (28.6, 39.3)
 just after Treat-All 61.9 7.6 57.7 86.5 42.2 34.2
  (95% CI) (61.1, 69.7) (5.3, 9.8) (53.2, 62.2) (84.8, 88.2) (40.6, 43.9) (29.3, 39.1)
 relative change −12.2% −73.8% −13.3% 1.4% 6.8% 0.6%

Slopes before and after Treat-All
 before Treat-All (95% CI) 1.1 (0.6, 1.7) −0.4 (−0.5, −0.2) 0.5 (0.3, 0.7) 0.1 (−0.1, 0.2) −0.5 (−0.5, −0.4) −1.1 (−1.3,-0.9)
 after Treat-All (95% CI) −2.6 (−2.9, −2.2) −0.3 (−0.3, −0.2) −2.3 (−2.4, −2.1) −0.6 (−0.7, −0.5) −0.7 (−0.7, −0.6) −1.4 (−1.6,-1.3)
 p-value 0.055 <0.001 <0.001 <0.001 <0.001 <0.001

Abbreviation: CI, confidence interval.

*

Risk differences at the national Treat-All adoption threshold are from regression discontinuity analyses using Imbens-Kalyanaraman (IK) bandwidths derived from all data available within two years before and after the threshold to estimate the difference in local linear predictions. The bandwidth defines the area on each side of the threshold where the relationship between antiretroviral therapy (ART) start and pre-ART CD4 testing is assumed to be linear in local linear regression models.

Slope comparison is from separate linear regression models comparing the percentage point change per month before and after Treat-All using all data available within two years before and after national Treat-All adoption.