study | year | sample size | intervention measure | outcome indicator | |||
IG | CG | IG | CG | frequency | |||
F. T. Ji [12] | 2016 | 28 | 27 | Oral drip of colostrum | Saline drip | Once every 4 h, 0.2 ml each time, for seven days | A, B |
X. J. Zhao [13] | 2017 | 20 | 20 | Oral drip of colostrum | Saline drip | Once every 4 h, 0.2 ml each time, for seven days | A |
C. Y. Chen [14] | 2018 | 46 | 46 | Oral drip of colostrum | Saline drip | Once every 4 h, 0.2 ml each time, for seven days | A, B, C, D |
S. X. Cao [15] | 2018 | 20 | 20 | Colostrum oral smear | Sterile water smear | Once every 3 h | B, E |
Once every 6 h | |||||||
L. F. Chen [16] | 2017 | 30 | 30 | Colostrum oral smear | Normal saline smear | Once every 3 h, for two weeks | B, C, D, E |
Y. X. Zhang [9] | 2017 | 27 | 28 | Oral drip of colostrum | Saline drip | Once every 4 h, 0.2 ml each time, For seven days | C, E, G, H |
Glass K. [11] | 2017 | 17 | 13 | Oral drip of colostrum | Sterile drop injection | Once every 3 h, 0.2 ml each time | C, E, G, H |