G-CSF responsiveness, transplanted CD34⁺ cell number, and risk of infection. Analyses for an association of the rate of documented infection with (A) subgroups for G-CSF responsiveness (first transplantation, P = .0002; second transplantation, P = .016; chi2 test for trend) and (B) categories of the number of transplanted CD34⁺ cells (×106/kg) (first transplantation, P = .62; second transplantation, P = .81).