The multivariable models indicate that the association between initial PTH phenotype and both recovery time and PTH at 3 months after injury was significant while adjusting for age and sex (time to recovery: hazard ratio, 0.64; 95% CI, 0.43-0.93; P = .02; headache at 3 months: odds ratio, 3.08; 95% CI, 1.14-9.92; P = .02). Here, PTH is linked to Headache.