Fig. 5

Variations in mean enzymatic activities at 20 °C across a subgroup of 5 laboratories. Samples: (a) saliva, (b) pancreatin, (c) α-amylase M and (d) α-amylase S. Scatter plots show individual lab means. Box plots: median (thick lines), interquartile range (box), 1.5 × interquartile range (whiskers). Black “x” symbols and lines over the boxplots: mean results of all labs and corresponding standard deviations (excluding outliers).