Fig. 2

A1-A3: Trend charts and predicted mean curves for LCA, LAD, and RCA. The black line is the predicted value, and the red line is the prediction interval with 95% confidence. B1 ~ B3: studentized residual diagrams for LCA, LAD, and RCA. The black line is the normal curve, and the red line is the estimated curve. C1 ~ C3: Z score scatter plots for LCA, LAD, and RCA, which represent the fitted values of the regression models, along with upper and lower bounds, i.e. 2 and − 2 z-scores, respectively