2014年的研究STONE計分:用來預測沒有併發症的尿路結石，
指出若計分為高可能性的這一群，應該是可以免去進一步CT檢查。
這個評分當然得接受外部挑戰，
在2016年Annals of Emergency Medicine的這篇研究中，
利用之前進行的一個隨機大型結石研究資料進一步分析，Ultrasonography versus computed tomography for suspected nephrolithiasis. (NEJM 2014),
STONE score比醫師的猜測來得準些，但AUC=0.78並不算很好
下圖所示，確實可以依評分的分類來預測尿路結石，
分數愈高，結石的可能性愈高，其他原因的可能就愈低，
但是比原始研究結果差。
而且其中的一項指標Race並不足以用來做為預測之用
最高分數的這組，Sensitivity 53%, Specificity 87%，
因此雖然可以用來預測尿路結石，
但仍不足以用來做為不用排CT檢查的依據。
External Validation of the STONE Score, a Clinical Prediction Rule for Ureteral Stone: An Observational Multi-institutional Study
Ralph C. Wang, MD,* Robert M. Rodriguez, MD, Michelle Moghadassi, MPH, Vicki Noble, MD, John Bailitz, MD, Mike Mallin, MD, Jill Corbo, MD, RDMS, Tarina L. Kang, MD, Phillip Chu, PhD, Steve Shiboski, PhD, and Rebecca Smith-Bindman, MD
Ann Emerg Med. 2016 Apr; 67(4): 423–432.e2.
Abstract
Study objective
The STONE score is a clinical decision rule that classifies patients with suspected nephrolithiasis into low-, moderate-, and high-score groups, with corresponding probabilities of ureteral stone. We evaluate the STONE score in a multi-institutional cohort compared with physician gestalt and hypothesize that it has a sufficiently high specificity to allow clinicians to defer computed tomography (CT) scan in patients with suspected nephrolithiasis.
Methods
We assessed the STONE score with data from a randomized trial for participants with suspected nephrolithiasis who enrolled at 9 emergency departments between October 2011 and February 2013. In accordance with STONE predictors, we categorized participants into low-, moderate-, or high-score groups. We determined the performance of the STONE score and physician gestalt for ureteral stone.
Results
Eight hundred forty-five participants were included for analysis; 331 (39%) had a ureteral stone. The global performance of the STONE score was superior to physician gestalt (area under the receiver operating characteristic curve=0.78 [95% confidence interval {CI} 0.74 to 0.81] versus 0.68 [95% CI 0.64 to 0.71]). The prevalence of ureteral stone on CT scan ranged from 14% (95% CI 9% to 19%) to 73% (95% CI 67% to 78%) in the low-, moderate-, and high-score groups. The sensitivity and specificity of a high score were 53% (95% CI 48% to 59%) and 87% (95% CI 84% to 90%), respectively.
Conclusion
The STONE score can successfully aggregate patients into low-, medium-, and high-risk groups and predicts ureteral stone with a higher specificity than physician gestalt. However, in its present form, the STONE score lacks sufficient accuracy to allow clinicians to defer CT scan for suspected ureteral stone.
