Table 3.

Multiple generalised linear regression analysis of the determinants of total mean monthly costs (US$)

Variables		Value	% change from referent	p-value
Time period relative to ART initiation (months)	-4 to 4	384 (321 to 459)	80%	<0.001
	4 to 12	238 (204 to 277)	12%	0.158
	12 to 24	Referent
	24 to 48	222 (182 to 270)	4%	0.705
Baseline CD4 count (cells/µL)	0 to 49	193 (164 to 227)	-10%	0.228
	50 to 199	Referent
Current CD4 count (cells/µL)	0 to 49	352 (290 to 426)	65%	<0.001
	50 to 199	Referent
	200 to 349	190 (161 to 223)	-11%	0.16
	350 to 499	166 (141 to 195)	-22%	0.002
	≥500	158 (123 to 202)	-26%	0.017
Baseline viral load (copies/ml)	<100 000	Referent
	≥100 000	220 (195 to 248)	3%	0.601
Current viral load (copies/ml)	<400	Referent
	400 to 9 999	219 (191 to 250)	3%	0.717
	10 000 to 99 999	195 (164 to 232)	-8%	0.317
	≥100 000	249 (209 to 296)	17%	0.082
Overall adherence	<42%	264 (235 to 297)	24%	<0.001
	42 to 74%	263 (233 to 295)	23%	0.001
	75 to 92%	244 (218 to 273)	14%	0.019
	≥92%	Referent
ARV regimen	First line	Referent
	Second line	409 (255 to 656)	92%	0.007
NNRTI in first line	Nevirapine	197 (182 to 213)	-8%	0.042
	Efavirenz	Referent
Duration of CD4 count monitoring (months)	≤6	181 (161 to 204)	-15%	0.008
	>6	Referent
Sex	Male	206 (188 to 226)	-3%	0.463
	Female	Referent
Age at starting ART (years)	<25	194 (164 to 230)	-9%	0.282
	25 to 50	Referent
	>50	230 (194 to 271)	8%	0.384
Referent cost		213 (178 to 256)	NA	NA