Table 1: Sample description of the ACTG175 study variables considered by the PRIM algorithm. The arms are labeled as 0 = zidovudine, 1 = zidovudine and didanosine, 2 = zidovudine and zalcitabine, 3 = didanosine.

Treatment Group

Variable

0 (n = 532)

1 (n = 522)

2 (n = 524)

3 (n = 561)

P-value

Age

≤ 30

(30,40]

(40,50]

> 50

 

166 (0.31)

237 (0.45)

102 (0.19)

27 (0.05)

 

164 (0.31)

233 (0.45)

101 (0.19)

24 (0.05)

 

164 (0.31)

235 (0.45)

95 (0.18)

30 (0.06)

 

177 (0.32)

251 (0.45)

111 (0.20)

22 (0.04)

0.984

Weight (kg)

≤ 60

(60,70]

(70,80]

> 80

 

44 (0.08)

138 (0.26)

177 (0.33)

173 (0.33)

 

63 (0.12)

126 (0.24)

175 (0.34)

158 (0.30)

 

58 (0.11)

132 (0.25)

172 (0.33)

162 (0.31)

 

66 (0.12)

132 (0.24)

192 (0.34)

171 (0.30)

0.749

Hemophilia

No

Yes

 

490 (0.92)

42 (0.08)

 

479 (0.92)

43 (0.08)

 

478 (0.91)

46 (0.09)

 

512 (0.91)

49 (0.09)

0.946

Homosexual activity

No

Yes

 

191 (0.36)

341 (0.64)

 

176 (0.34)

346 (0.66)

 

176 (0.34)

348 (0.66)

 

182 (0.32)

379 (0.68)

0.679

Karnofsky score

70

80

90

100

 

4 (0.01)

17 (0.03)

197 (0.37)

314 (0.59)

 

0 (0.00)

22 (0.04)

189 (0.36)

311 (0.60)

 

3 (0.01)

18 (0.03)

180 (0.34)

323 (0.62)

 

2 (0.00)

23 (0.04)

221 (0.39)

315 (0.56)

0.500

Prior antiretroviral therapy

No

Yes

 

516 (0.97)

16 (0.03)

 

513 (0.98)

9 (0.02)

 

511 (0.98)

13 (0.02)

 

552 (0.98)

9 (0.02)

0.350

Race

White

Non-white

 

376 (0.71)

156 (0.29)

 

384 (0.74)

138 (0.26)

 

374 (0.71)

150 (0.29)

 

388 (0.69)

173 (0.31)

0.452

Gender

Female

Male

 

100 (0.19)

432 (0.81)

 

88 (0.17)

434 (0.83)

 

89 (0.17)

435 (0.83)

 

91 (0.16)

470 (0.84)

0.708


Baseline CD4 count

≤ 15.3

(15.3,18.4]

(18.4,21.6]

> 21.6

 

75 (0.14)

182 (0.34)

197 (0.37)

78 (0.15)

 

98 (0.19)

175 (0.34)

171 (0.33)

78 (0.15)

 

88 (0.17)

175 (0.33)

173 (0.33)

88 (0.17)

 

86 (0.15)

197 (0.35)

201 (0.36)

77 (0.14)

0.528

Baseline CD8 count

≤ 6.32

(6.32,6.79]

(6.79,7.26]

> 7.26

 

72 (0.14)

197 (0.37)

190 (0.36)

73 (0.14)

 

79 (0.15)

173 (0.33)

183 (0.35)

87 (0.17)

 

69 (0.13)

181 (0.35)

195 (0.37)

79 (0.15)

 

88 (0.16)

192 (0.34)

203 (0.36)

78 (0.14)

0.813