OBJECTIVES: To assesses the quality of life (QoL) with Q-TwiST retrospectively in a randomised phase III trial with n-HFL patients comparing the use of filgrastim after peripheral blood progenitor cells reinfusion. METHODS: Multi-centre study conducted in France between 1995-1999 including 51 patients (24 placebo (P) and 27 filgrastim (FI)). Demographic, disease and treatment-specific information was collected through the CRF. QoL assessment per patient over 90 days of follow-up (FU) was calculated as follows: QoL-index valued from 0 (worst) to 1 (best) was used to assign QoL per hospital day: in sterile room (SR) = 0.6, in a normal room (NR) = 0.9. Each adverse event (AE) (WHO grade 3 or 4) affected the QoL index with an additional factor of 0.8, 0.6, 0.4 or 0.2 respectively for 1, 2, 3, ? 4 concomitant AEs per patient per day. Average QoL-scores over time per treatment arm were compared using Kaplan-Meier statistics (p < .05, two-sided). Sensitivity analysis on the score index over the FU was undertaken. RESULTS: For FI the average days with 0,1 0, 1, 2, 3, ? 4 AEs in a SR was 6.59, 4, 2.56, 0.81, 0.37 and in a NR 1.59, 1.67, 0.56, 0.11, 0. For P in a SR we had respectively 8.3, 3.8, 2.8, 2.2, 0.125 and in a NR: 2.13, 0.9, 0, 0, 0. Average estimated QoL-score was 81.71 for FI (SD: 3.15, range: 72.54 - 85.24) and 80.66 for C (SD: 3.01, range: 71.8 - 84.68) (Mann Witney U test: p = .49 but decreased to <0.25 for first hospitalization period. Kaplan-Meier graph demonstrates after day 16 a constant QoL benefit for FI due to earlier hospital discharge (Log rank test: 27.2; p<0.001). CONCLUSION: Filgrastim use 24 hours post-PBPC in high dose treatment of n-HFL patients is associated with QoL improvement due to earlier hospital discharge.