Fig 1.
Common tools for the assessment of growth: percentile charts (left panel) and z-score plots (right panel), modified from Fenton et al. 2013 and Griffin et al. 2014; colored lines and dots represent growth trajectories of three example infants.
Fig 2.
2A: Plotting of growth charts and calculation of z-scores, distribution (black line) of birth weights for a cohort of newborns with a gestational age of 28 and 34 weeks; 2B: Characteristics of growth charts: skewness of percentile distributions (top) and weight gain velocity for major percentiles (bottom).
Fig 3.
Method for the analysis of z-score differences in relation to weight gain velocity; the left panel shows how the reference data for weight gain velocity and z-score calculation were selected; the right panel shows the corresponding equations for z-score difference and weight gain ratio calculation.
Table 1.
Patient characteristics.
Fig 4.
Longitudinal assessment of growth: Zdiff versus WGR relationship.
Scatter plots show individual data and the regression line calculated for the complete data set (panel A), as well as a set of regression lines stratified by birth weight (panel B), gestational age (panel C) and length of observation period (panel D), colours represents stratification for four different parameters as indicated in legends. Dotted red box (panel A) shows proportion of infants which show a WGR>1 and negative z-score.