Kelleher C
Office of Health Services Research, Baltimore U.S. Public Health Service Hospital, MD.
Health Serv Res. 1993 Feb;27(6):841-55.
In a concurrent prospective study, medical and surgical residents rated the severity of illness and difficulty of clinical management of each of their patients within 24 hours of admission, and on a daily basis throughout the patient's stay. Data were collected on consecutive admissions resulting in 661 admissions with complete data for analysis. Results indicate that difficulty and severity are correlated, each explaining variations in length of stay (LOS), and together explaining up to 44 percent. Four alternative measures are tested, first-day values, average values over the stay, peak or highest values, and a zero-one measure indicating whether or not the severity or difficulty fluctuated over the stay. First-day and average measures of severity and difficulty explain little variation in LOS; peak and fluctuating measures are highly explanatory. After adjusting for diagnosis-related groups (DRGs), fluctuating severity adds 34 percent, and adjusting for both DRGs and severity, fluctuating difficulty adds 10 percent for a total of 53 percent variance explained. In comparable results, peak severity adds 21 percent, and peak difficulty 4 percent, for a total of 34 percent variance explained. Findings indicate that difficulty had independent value as a predictor, and the high explanatory power of the fluctuating measures suggests that a third dimension, instability, may be as important as severity and difficulty in explaining LOS.
在一项同期前瞻性研究中，内科和外科住院医师在患者入院后24小时内以及患者住院期间每天对每位患者的疾病严重程度和临床管理难度进行评分。收集了连续入院患者的数据，共有661例入院患者有完整数据用于分析。结果表明，难度和严重程度相关，二者均能解释住院时间（LOS）的变化，共同解释的比例高达44%。测试了四种替代指标，即首日值、住院期间的平均值、峰值或最高值，以及一种0-1指标，用于表明严重程度或难度在住院期间是否波动。首日和平均严重程度及难度指标对住院时间变化的解释力很小；峰值和波动指标的解释力很强。在对诊断相关分组（DRG）进行调整后，波动的严重程度增加了34%，在对DRG和严重程度都进行调整后，波动的难度增加了10%，总共解释了53%的方差。在类似结果中，峰值严重程度增加了21%，峰值难度增加了4%，总共解释了34%的方差。研究结果表明，难度作为一个预测指标具有独立价值，波动指标的高解释力表明，在解释住院时间方面，第三个维度——不稳定性，可能与严重程度和难度同样重要。
