Table 1. Baseline characteristics of study participants at enrollment, Malawi, 2002–2004*.

Characteristic	No. episodes	PYO
CD4 (cells/mm3)
0–99	125	83
100–199	159	145
200–499	271	268
>500	77	75
Missing at enrollment	28	19
HIV clinical stage†
I	267	255
II	191	190
III	160	120
IV	42	25
Total	660	591

*PYO, person-years of observation (based on enrollment characteristics).
†As defined by World Health Organization criteria.