Statistical analysis
REGRESSION
Statistical analysis was done independently by two investigators (CR and MHO) using SAS/STAT software (SAS Institute Inc.) and R (version 4.1.0, R Core Team), respectively. The plan for statistical analysis was pre‐published at The mean and SD were used if variables were normally distributed: if not, data were presented as the median and interquartile range (IQR). A quantile‐quantile plot and the Shapiro–Wilk test were used to investigate distribution. Dichotomous demographic data were presented as numbers and percentages.To correct for multiple comparisons, we adjusted the alpha level as suggested by Jakobsen et al. (Comparison of HRV in the supine and upright positions and between patients and healthy volunteers in supine was done using paired As further post hoc exploratory analyses, we correlated individual HRV measures with each other, with age and days from injury using Pearson correlations coefficient. Finally, we also carried out mixed effects linear regression models investigating if age (corrected for group allocation) and/or mobilization would influence the HRV measures.