observational
adjective uk/ˌɒb.zəˈveɪ.ʃən.əl/ us/ˌɑːb.zɚˈveɪ.ʃən.əl/
观察的，观测的
involving watching someone or something carefully and closely, in order to learn something
Observational research uses data collected during routine clinical care. 观察性研究采用在日常临床护理中收集的数据。