Mitchell Alice M, Garvey J Lee, Chandra Abhinav, Diercks Deborah, Pollack Charles V, Kline Jeffrey A
Department of Emergency Medicine, Carolinas Medical Center, Charlotte, NC 28323-2861, USA.
Ann Emerg Med. 2006 May;47(5):447. doi: 10.1016/j.annemergmed.2005.10.013. Epub 2006 Jan 19.
We compare the diagnostic accuracy of 3 methods--attribute matching, physician's written unstructured estimate, and a logistic regression formula (Acute Coronary Insufficiency-Time Insensitive Predictive Instrument, ACI-TIPI)--of estimating a very low pretest probability (< or = 2%) for acute coronary syndromes in emergency department (ED) patients evaluated in chest pain units.
We prospectively studied 1,114 consecutive patients from 3 academic EDs, evaluated for acute coronary syndrome. Physicians collected data required for pretest probability assessment before protocol-driven chest pain unit testing. A pretest probability greater than 2% was considered "test positive." The criterion standard was the outcome of acute coronary syndrome (death, myocardial infarction, revascularization, or > 60% stenosis prompting new treatment) within 45 days, adjudicated by 3 independent reviewers.
Fifty-one of 1,114 enrolled patients (4.5%; 95% confidence interval [CI] 3.4% to 6.0%) developed acute coronary syndrome within 45 days, including 4 of 991 (0.4%; 95% CI 0.1% to 1.0%) patients, discharged after a negative chest pain unit evaluation result, who developed acute coronary syndrome. Unstructured estimate identified 293 patients with pretest probability less than or equal to 2%, 2 had acute coronary syndrome, yielding sensitivity of 96.1% (95% CI 86.5% to 99.5%) and specificity of 27.4% (95% CI 24.7% to 30.2%). Attribute matching identified 304 patients with pretest probability less than or equal to 2%; 1 had acute coronary syndrome, yielding a sensitivity of 98.0% (95% CI 89.6% to 99.9%) and a specificity of 26.1% (95% CI 23.6% to 28.7%). ACI-TIPI identified 56 patients; none had acute coronary syndrome, yielding sensitivity of 100% (95% CI 93.0% to 100%) and specificity of 6.1% (95% CI 4.7% to 7.9%).
In a low-risk ED population with symptoms suggestive of acute coronary syndrome, patients with a quantitative pretest probability less than or equal to 2%, determined by attribute matching, unstructured estimate, or logistic regression, may not require additional diagnostic testing.
我们比较了三种方法——属性匹配、医生书写的非结构化评估以及逻辑回归公式（急性冠状动脉供血不足-时间不敏感预测工具，ACI-TIPI）——在胸痛单元评估的急诊科（ED）患者中估计急性冠状动脉综合征极低的预检概率（≤2%）的诊断准确性。
我们对来自3个学术性急诊科的1114例连续患者进行了前瞻性研究，评估其急性冠状动脉综合征情况。在方案驱动的胸痛单元检测前，医生收集预检概率评估所需的数据。预检概率大于2%被视为“检测阳性”。标准参照为45天内急性冠状动脉综合征的结局（死亡、心肌梗死、血管重建或因狭窄>60%而采取新的治疗措施），由3名独立评审员判定。
1114例入组患者中有51例（4.5%；95%置信区间[CI]3.4%至6.0%）在45天内发生了急性冠状动脉综合征，其中991例胸痛单元评估结果为阴性后出院的患者中有4例（0.4%；95%CI0.1%至1.0%）发生了急性冠状动脉综合征。非结构化评估确定了293例预检概率小于或等于2%的患者，其中2例发生了急性冠状动脉综合征，敏感性为96.1%（95%CI86.5%至99.5%），特异性为27.4%（95%CI24.7%至30.2%）。属性匹配确定了304例预检概率小于或等于2%的患者；1例发生了急性冠状动脉综合征，敏感性为98.0%（95%CI89.6%至99.9%），特异性为26.1%（95%CI23.6%至28.7%）。ACI-TIPI确定了56例患者；均未发生急性冠状动脉综合征，敏感性为100%（95%CI93.0%至100%），特异性为6.1%（95%CI4.7%至7.9%）。
在有急性冠状动脉综合征症状的低风险急诊科人群中，通过属性匹配、非结构化评估或逻辑回归确定预检概率小于或等于2%的患者可能无需额外的诊断检测。
