Table 2.

Description Of Change Parameters For Clinical And Medical Variables

Variable	Change measurement	Subgroup classification
CD4 count	Crossed a boundary value of 200 cells/μL in either direction	Stable: CD4 count consistently above or below 200 cells/μL at both visits Change: CD4 count increased or decreased past boundary value of 200 cells/μL between assessments
Viral load	Crossed a boundary value of detectable virus (50 copies/μL)	Stable: consistently undetectable or detectable at both visits Change: viral load at follow-up visit different from baseline visit
Illicit substance use	Urine toxicology test for use of illicit substances	Stable: consistently positive or negative at each visit Change: status at follow-up visit different from baseline visit
Cognitive status	sRCS	Stable: sRCS value remained within 90% CI Decline: Bottom 5% sRCS values Improvement: Top 5% sRCS values

Note. sRCS = standard regression-based change score; CI = confidence interval.