California Ambulatory Surgery Data, July - December 2009

The dataset is released twice a year and contains files for ambulatory surgery and emergency data. Ambulatory Surgery data include encounters from general acute care hospitals and licensed free standing ambulatory surgery clinics, during which at least one ambulatory surgery procedure is performed. Emergency Department data includes encounters from hospitals licensed to provide emergency medical services. To protect patient confidentiality, records with unique combinations of certain demographic variables will have one or more of those variables masked. These are detailed in Appendix A of the documentation.Each record in the dataset consists of one outpatient encounter for each time a patient is treated. Data collected for these encounters include demographic, clinical payer, and facility information.

本数据集每半年发布一次，涵盖门诊手术（Ambulatory Surgery）与急诊两类数据文件。其中门诊手术数据包含综合急性护理医院及持牌独立门诊手术诊所的就诊记录，此类就诊均完成至少一例门诊手术操作；急诊科室（Emergency Department）数据则涵盖持牌提供急诊医疗服务的医院的就诊记录。
为保护患者隐私，部分人口统计学变量（Demographic Variables）组合唯一的记录，将对其中一项或多项变量进行掩码处理，相关细节详见文档附录A。
数据集中的每条记录对应患者单次就诊的门诊就诊事件，采集的信息包括人口统计学信息、临床信息、支付方信息及医疗机构相关信息。