This study aims to assess the interrater reliability of the CTAS in current clinical practice, that is, as used by experienced ED nurses without recent certification or recertification.
A prospective sample of 100 patients arriving by ambulance was identified and yielded a set of 100 written scenarios. Five experienced ED nurses reviewed and blindly assigned a CTAS score to each scenario. The agreement among nurses was measured using the Kappa statistic calculated with quadratic weights. Kappa values were generated for each pair of nurses and a global Kappa coefficient was calculated to measure overall agreement.
Overall interrater agreement was moderate, with a global Kappa of 0.44 (95%confidence interval 0.40-0.48). However, pairwise, Kappa values were heterogeneous (0.30 to 0.61, p = 0.0013).
The moderate interrater agreement observed in this study is disappointingly low and suggests that CTAS reliability may be lower than expected, and this warrants further research. Intra-observer reliability of聽CTAS should be ascertained more extensively among experienced nurses, and a future evaluation should involve several institutions.