Goldstein L B, Chilukuri V
Division of Neurology, Durham Department of Veterans Affairs Medical Center, NC, USA.
Stroke. 1997 Jun;28(6):1181-4. doi: 10.1161/01.str.28.6.1181.
The severity of the initial neurological deficit is a critical determinant of outcome after acute stroke. Retrospective outcome studies are generally limited by a lack of quantitative data relating to this initial stroke severity. We evaluated the validity and reliability of measuring initial stroke severity retrospectively with the Canadian Neurological Scale (CNS).
The CNS was used to prospectively score the initial neurological deficit in a series of patients with acute ischemic stroke (n = 24). An algorithm was devised for applying the CNS retrospectively on the basis of information in the patient's hospital discharge summary. Those dictating the discharge summaries were not aware of the study, and the retrospective scoring was performed without reference to other scores. The level of agreement between the prospective and retrospective scores (validity) and both intraobserver and interobserver reliability for the retrospective scores were determined.
Agreement was high between retrospective and prospective scores (r = .84, R2 = .71, P < .0001), between two sets of retrospective scores obtained by one rater (r = .95, R2 = .91, P < .0001), and between retrospective scores obtained by different raters (r = .91, R2 = .82, P < .0001). Weighted kappa statistics (kappa w) for prospectively versus retrospectively scored items varied from almost perfect (kappa w > 0.81 for level of consciousness and orientation) to substantial (kappa w = 0.68 for speech) and moderate (kappa w = 0.41 to 0.60 for facial weakness, proximal arm, distal arm, proximal leg, and distal leg strength). Using the retrospective algorithm, there was almost perfect intraobserver and interobserver reliability for each of the individual CNS items (kappa w = 0.81 to 1.00).
These data show that retrospective scoring of initial stroke severity using an algorithm based on the CNS is valid and can be reliably performed using information available in hospital discharge summaries.
急性卒中后，初始神经功能缺损的严重程度是预后的关键决定因素。回顾性预后研究通常因缺乏与初始卒中严重程度相关的定量数据而受到限制。我们评估了使用加拿大神经功能量表（CNS）回顾性测量初始卒中严重程度的有效性和可靠性。
使用CNS对一系列急性缺血性卒中患者（n = 24）的初始神经功能缺损进行前瞻性评分。根据患者出院小结中的信息，设计了一种算法用于回顾性应用CNS。撰写出院小结的人员对该研究不知情，回顾性评分在不参考其他评分的情况下进行。确定前瞻性和回顾性评分之间的一致性水平（有效性）以及回顾性评分的观察者内和观察者间可靠性。
回顾性和前瞻性评分之间的一致性较高（r = 0.84，R2 = 0.71，P < 0.0001），同一评分者获得的两组回顾性评分之间的一致性较高（r = 0.95，R2 = 0.91，P < 0.0001），不同评分者获得的回顾性评分之间的一致性较高（r = 0.91，R2 = 0.82，P < 0.0001）。前瞻性与回顾性评分项目的加权kappa统计量（kappa w）从几乎完美（意识水平和定向的kappa w > 0.81）到实质性（言语的kappa w = 0.68）和中等（面部无力、近端上肢、远端上肢、近端下肢和远端下肢力量的kappa w = 0.41至0.60）不等。使用回顾性算法，每个CNS单项的观察者内和观察者间可靠性几乎完美（kappa w = 0.81至1.00）。
这些数据表明，使用基于CNS的算法对初始卒中严重程度进行回顾性评分是有效的，并且可以使用出院小结中的可用信息可靠地进行。
