To assess the impact of observer’s experience on reliability of etiological classification systems in patients with ischemic stroke.
We retrospectively reviewed medical records of 80 patients with ischemic stroke in hospitals from August 2016 to March 2017 consecutively. Patients were classified by 4 observers with different clinical experiences and backgrounds (A, B, C, and D) according to the Trial of ORG 10172 in Acute Stroke Treatment (TOAST), Stop Stroke Study TOAST (SSS-TOAST), and ASCOD (A-atherosclerosis, S-small vessel disease, C-cardiac pathology, O-other cause, and D-dissection). The intraobserver reliability was assessed based on the initial and a second delayed assessment after 3 months, and the interobserver reliability of different pairs (A-B and C-D) and overall (A, B, C, and D) were compared based on the initial classification.
The reliability values of the 3 classification systems were improved with observer’s experience increasing, particularly in the TOAST system, in which the intraobserver reliability values of observers A, B, C, and D were 0.62, 0.73, 0.80, and 0.88, respectively, and slight differences were observed between the SSS-TOAST and ASCOD systems. The A-B pair had lower interobserver reliability value than the C-D pair, particularly in TOAST system with reliability values of 0.36 and 0.74, respectively, and a slight variation of interobserver reliability values were noted in the SSS-TOAST and ASCOD system.
Observer’s experience may affect the reliability of etiological classification systems in patients with ischemic stroke.
*Department of Neurology, the Fifth People’s Hospital of Shanghai, Fudan University
†Department of Neurology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University
‡Department of Neurology, Changhai Hospital, Second Military Medical University, Shanghai, China
X.-L.Y. and D.-S.Z. contributed equally.
Supported by the Natural Science Foundation of China (no. 81230027), the Postdoctoral Science Foundation of China (no. 2014M560297), the Translational Medicine Collaborative Innovation Cooperation Research Project (TM201706), Medical-Engineering Cross Fund of Shanghai Jiao Tong University (no. YG2013MS23).
The authors declare no conflict of interest.
Correspondence to: Yang-Tai Guan, MD, PhD, Department of Neurology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No. 160, Pu Jian Road, Shanghai 200127, China. E-mail: firstname.lastname@example.org.