“…Thirty-seven trials reported the level of consciousness (according to GCS) before treatment [20–23, 25, 27–30, 32–58], and GCS score was used in 28 studies as the outcome measure [20–23, 25, 27–30, 32, 33, 35–39, 41, 42, 44–48, 54–56, 58]. Twenty-two studies used continuous data, and the statistic used was the difference in GCS score before and after treatment [20, 21, 23, 27–30, 32, 33, 36–39, 41, 42, 44–46, 48, 54, 55]. The GCS results showed high heterogeneity ( I 2 =72%), so we did a subgroup analysis according to the treatment duration, TBI's degree (we define the GCS score between 3 and 8 as severe TBI, 8 and 12 as moderate TBI, and 13 and 15 as mild TBI), and intervention.…”