Fig. 4.

a, b Risk factors for the 2-year motor skills (including death) endpoint from the fitted multivariate logistic regression model; variables included based on the univariate analysis (those with p value < 0.1). a using first log₁₀ sNfL measured, PIVH visit; b using highest log₁₀ sNfL measurement. GA, gestational age; PIVH, peri/intraventricular hemorrhage. c Smoothed receiver operating characteristic (ROC) curves for the predictive value of early serum NfL (sNfL, solid black line) for the 2-year motor skills (or death) endpoint [AUC 0.64 (0.47–0.81)]; also shown is the predictive value of the highest sNfL level [dotted black line, AUC 0.71 (0.54–0.88)]; the nearer the curve is to the top left corner, the better the predictive value. d Log₁₀ serum NfL (sNfL) measurements plotted against time of measurement (in days) from the general additive model using restricted cubic splines fitted for time with 3 knot points; marginal model stratified by the composite 1-year poor motor skills (or death) endpoint