Figure 1.

Serum (S-) and erythrocyte (ER-) folate concentrations were measured prior to therapy and before each cycle of high dose methotrexate. Relative cycle-to-cycle differences (Δ) are shown using first cycle pretreatment concentrations as baseline. Interindividual variation in 65 patients at each cycle is illustrated as 95% confidence intervals of mean relative differences. Polynomial regression curves are fitted to the experimental data to indicate dependency of cycle number