a nonsignificant trendp = 0.08
One study comparing young (< 30 years) and older (> 75 years) individuals revealed upregulation of p21, p53, and MMP‐9 after injury only in young subjects, with a nonsignificant trend for p16 ( p = 0.08) and no induction in aged skin ( p = 0.25) (Chia et al. 2021 ).