Figure 2: Hand kinetic tremor quantified by tremor amplitude of digital Archimedes spirals drawn by cases and controls.
(Panel A) Box plots of Ln(tremor amplitude) for individual spirals drawn by cases and controls. Each box illustrates the median (heavy line) and upper and lower quartile boundaries for the population presented. Whiskers illustrate the highest and lowest individual data points that are no more than 1.5 times the interquartile range (IQR); any points falling outside this limit represent suspected outliers. Filled symbols represent individuals with classic galactosemia (cases); open symbols represent individuals without galactosemia (controls). Circles represent females; squares represent males. The dotted horizontal line marks the 95% cutoff for controls. (Panel B) Proportion of cases and controls presenting 0, 1, 2, 3, or 4 spirals with tremor amplitude scores above the 95th percentile cutoff defined for controls. (Panel C) Individual spiral RMS scores for cases and controls as a function of age. The solid line presents a best-fit curve to the combined data, and the shaded area represents the 95% range for all subjects (cases and controls).