Category: Clinical Stones: PCNL

MP12-8 - Interobserver variability among senior and fresh graduates surgeons in assessment of Guy’s stone score and S.T.O.N.E. nephrolithometric score: a prospective evaluation.

Fri, Sep 21
2:00 PM - 4:00 PM

Introduction & Objective : The present study aimed at assessing the interobserver variability among the senior and fresh graduates surgeons in a developing country; performing the PCNL and compared the scoring done by the both groups of surgeons for the Guy’s stone score and S.T.O.N.E. nephrolithometry score.


Methods : Patients underwent PCNL between January 2016 and October 2017 were prospectively enrolled. Preoperative computed tomography was done in all these patients. The Guy’s stone score and S.T.O.N.E. nephrolithometry score were calculated by 6 senior surgeons (more than 5 years endourology experience independently) and 7 junior surgeons (less than one year of endourology experience independently). All patients underwent either standard adult size PCNL by the senior consultants or junior consultants. Consistency among the scores was assessed using Cronbach’s alpha. Each score was compared between the two groups for the stone free rates achieved and the complications incurred (operatively and postoperatively).Independent t test was used for continuous variables and chi square test was used to compare the categorical variables between the two groups value less than 0.05 was considered statistically significant.


Results : The mean Guy’s grade was 1.5 and 1.4 while the mean S.T.O.N.E. score was 8.1 and 7.9 in the two groups respectively (P=0.06). The mean operative time was 140±64 minutes and 155 minutes while  hospital stay was 2.3 and  1.9 days in senior and junior surgeons group respectively (P=0.07). Mean fluoroscopy time was 6.2±1.2 minutes and 7.4 minutes (P=0.08). The mean Guys score was 1.3 and 1.2 in the stone free patients in the two surgeons operated groups (p=0.07).The  S.T.O.N.E. score was 7.8 and 7.6 in the two surgeon groups (P=0.06) for stone free patients. Both scores were strongly correlated to operative time (p value 0.008 for Guys and 0.013 for STONE score) in the senior surgeons group. Similarly these scores well predicted the operative time in the junior surgeons group as well (P=0.004).


Conclusions : More complications were seen in higher Guys and STONE scores in junior group.Both of the surgeons groups had good interobserver reproducibility of scores accurately.

Nadeem Iqbal

Resident/fellow urology
Shifa International hospital,PKLI
Islamabad, Islamabad, Pakistan

Imran Jamil

Consultant urology
Shifa International hospital,PKI
Islamabad, Islamabad, Pakistan

Saeed Akhter

professor and Head department
Shifa International hospital,PKI
Islamabad, Islamabad, Pakistan