@article{kuan-hung chen2023influencing,
  title={Factors influencing length of hospital stay in patients using patient-controlled analgesia after laparotomy surgery-retrospective observational study},
  author={hung-chieh chen,yu-huan tsou,chia-kai liu,kuan-hung chen,chien-hui yang},
  journal={Signa Vitae},
  volume={19},
  number={2},
  pages={111--122},
  doi = {10.22514/sv.2022.052},
  year={2023}
}