Statistical analysis
The normal distribution of data was analyzed by the D’Agostino and
Pearson omnibus normality test. To remove outliers from normally
distributed healthy control individuals, the Rout test was performed.
The selection of optimal cut-off values was based on curves constructed
by plotting the calculated specificity and sensitivity vs. the
corresponding cut-off values. Statistical significance was evaluated
using either parametric tests: paired-samples Student t-test and
unpaired-samples Student t-test with Welch correction, or non-parametric
tests: Wilcoxon matched-pairs signed-rank test or Mann-Whitney U-test
for unpaired data, when applicable. Calculations were performed using
GraphPad Prism version 6.01 for Windows (GraphPad Software, San Diego
California, USA, www.graphpad.com). A p-value < 0.05 was
considered statistically significant.