Funding for this research was provided by:
National Natural Science Foundation of China (81773540, 82173627)
Received: 20 October 2020
Accepted: 7 September 2021
First Online: 20 September 2021
: The Ethics Committee of the Fourth Military Medical University approved the current study. Written informed consent was provided by all recruited caregivers prior to the study, and the study complied with related regulations and guidelines. Data were collected anonymously.
: All participants have given informed consent and have given consent for publication.
: The authors declare that they have no competing interests.