For more than 30 years, the models that researchers and government agencies use to forecast earthquake aftershocks have remained largely unchanged.

Introduction Urolithiasis (or nephrolithiasis) is a relatively common disease affecting 113% of the global population and is more common in Jordan affecting 5.95% of the Jordanian population.1,2 It has a predilection for obese Caucasian men and carries significant morbidity, its prevalence being on the rise over the last four decades. Several procedures are currently in use for the management of kidney stones, including extracorporeal shockwave lithotripsy (ESWL), ureteroscopic lithotripsy (URSL), and percutaneous nephrolithotomy (PCNL). With each having its own indications, PCNL remains the golden standard for large renal stones measuring greater than 2 cm, staghorn stones, and partial staghorn stones.3 PCNL is not free of complications and its efficacy can be variable; therefore, few pre-operative nomograms are in place to help predict success rates, namely stone-free status, and possible complications, and nomograms help to systemize the reporting and interpretation of the surgerys outcomes.4 Examples of such nomograms are the S.T.O.N.E score, S-ReSC score, Guys Stone Score (GSS), and CROES nephrolithometry score.

Data collection and processing The physical examination data were derived from three hospitals, First Affiliated Hospital of Wannan Medical College, Beijing Luhe Hospital of Capital Medical University, and Daqing Oil field General Hospital. The three datasets were named as D1, D2, and D3, respectively. The first step was data cleaning, in which samples with missing values and abnormal values were excluded