Figure 1
From: Estimation of autistic children by metallomics analysis
Histogram of logarithmic zinc concentration in autistic children (N = 1,967).
The histogram of scalp hair zinc concentrations for 1,967 children (1,553 males and 414 females) aged 0–15 years is shown in the logarithm. The numbers on the abscissa indicate the logarithms of scalp hair zinc concentrations (ng g−1: ppb). The height of each rectangle represents the frequency in the class interval in logarithmic hair zinc level. Two dotted vertical lines represent the ±2 S.D. levels of the reference range of hair zinc concentrations.
