Data from: Exploring emergency department 4-hour target performance and cancelled elective operations: a regression analysis of routinely collected and openly reported NHS trust data.

Objective: To quantify the effect of intra-hospital patient flow on Emergency Department (ED) performance targets and indicate if the expectations set by the NHS England five year forward review are realistic in returning emergency services to previous performance levels. Design: Linear regression analysis of routinely reported trust activity and performance data using a series of cross-sectional studies. Setting: NHS trusts in England submitting routine nationally reported measures to NHS England. Participants: 142 acute non-specialist trusts operating in England between 2012 and 2016. Main outcome measures: The primary outcome measures were: proportion of four-hour waiting time breaches and cancelled elective operations. Methods: Univariate and multivariate linear regression models were used to show relationships between the outcome measures, and various measures of trust activity including: empty day-beds, empty night-beds, day-to-night bed ratio, ED conversion ratio and delayed transfers of care. Results: Univariate regression results using the outcome of four-hour breaches showed clear relationships with: empty night-beds and ED conversion ratio between 2012-2016. The day-to-night bed ratio showed an increasing ability to explain variation in performance between 2015-2016. Delayed transfers of care showed little evidence of an association. Multivariate model results indicated that the ability of patient flow variables to explain four-hour target performance had reduced between 2012-2016 (19% to 12%), and had increased in explaining cancelled elective operations (7% to 17%). Conclusions: The flow of patients through trusts is shown to influence ED performance, however performance has become less explainable by intra-trust patient flow between 2012 and 2016. Some commonly stated explanatory factors such as delayed transfers of care showed limited evidence of being related. The results indicate some of the measures proposed by NHS England to reduce pressure on EDs may not have the desired impact on returning services to previous performance levels.

研究目标：本研究旨在量化医院内部患者流动对急诊科（Emergency Department, ED）绩效目标的影响，并评估英国国民保健署英格兰分部（NHS England）《五年远期规划》中提出的、将急诊服务恢复至既往绩效水平的目标是否具备现实可行性。
研究设计：采用一系列横断面研究，对常规上报的医疗信托机构运营与绩效数据开展线性回归分析。
研究场景：英国境内向英国国民保健署英格兰分部（NHS England）上报常规全国性绩效指标的国民保健署医疗信托机构。
研究对象：2012年至2016年间在英格兰境内运营的142家急性病非专科医疗信托机构。
主要结局指标：核心结局指标包括四小时候诊超时占比与择期手术取消率。
研究方法：采用单变量及多变量线性回归模型，分析结局指标与多项医疗信托机构运营指标的关联，其中运营指标涵盖日间空病床数、夜间空病床数、日间-夜间病床比、急诊科转诊率及延迟出院转诊情况。
研究结果：针对四小时候诊超时结局的单变量回归结果显示，2012-2016年间其与夜间空病床数及急诊科转诊率存在显著关联；日间-夜间病床比对绩效变异的解释能力在2015-2016年间逐步提升；延迟出院转诊则未显示出明显关联。多变量模型结果表明，患者流动变量对四小时绩效目标的解释能力在2012-2016年间有所下降（从19%降至12%），而对择期手术取消率的解释能力则有所提升（从7%升至17%）。
研究结论：研究证实，医疗信托机构内部的患者流动会对急诊科绩效产生影响，但2012至2016年间，医院内部患者流动对绩效的解释力逐渐减弱。部分被广泛提及的影响因素（如延迟出院转诊）并未显示出与绩效显著相关的证据。本研究结果提示，英国国民保健署英格兰分部提出的部分旨在缓解急诊科压力的措施，或许无法达成恢复急诊服务至既往绩效水平的预期效果。