The SCQ-SCORE: initial validation of a new scoring system for elective stone surgery prioritization in the COVID-19 era

Abstract

Introduction: Endourology waiting lists have increased during the COVID-19 pandemic and prioritization strategies are needed. Some tiered classifications have been put forward aimed at prioritizing patients by using criteria related with clinical severity or social impact of stone disease, yet no quantitative system has been published to date. The objective of this study is to present a new quantitative scoring system for elective stone surgery prioritization and show its intra- and inter-rater reliability.

Material and methods: A scoring system coined 'SCQ-score' was set up, which consists of 9 variables: infection (ranges 0-3), obstruction (0-3), indwelling time (0-3), admissions (0-3), symptoms (0-2), ureteral location (0-1), solitary or suboptimal kidney (0-1), chronic kidney disease (0-1) and presence of percutaneous nephrostomy (0-1).The intra- and inter-rater reliability of the SCQ-score was prospectively validated in 60 consecutive patients on the waiting list, by calculating the intraclass correlation coefficient (ICC).

Results: The SCQ-score demonstrated having an excellent interobserver agreement (ICC >0.75) for the final score and its different domains. After 4 weeks, a second analysis was carried out to measure its intra-rater reliability, which was also excellent. On average, 134.9 ±50 seconds were required to complete the SCQ-score.

Conclusions: The SCQ-score is a new quantitative system to help prioritize elective stone surgeries, which has been shown to be user-friendly and to have an excellent intra- and inter-rater reliability. Initially developed to help during the COVID-19 pandemic, its utility will probably remain of interest in the post-COVID-19 era to ensure a fairer access to stone surgery.

Keywords: renal stones; ureteral stones; urolithiasis.

Figure 1

Flowchart diagram of the SCQ-score design.

Figure 2

Practical application of the SCQ-score in three different cases of our series. Case 1. Solitary stone in lower pole. Asymptomatic, no obstruction or infection. No admissions while on waiting list. Normal renal function. No stents. Case 2. Ureteric stone. Pyonephrosis that required double J stent placement 4 months ago. Now asymptomatic. GFR 50 ml/min. Case 3. Renal pelvis stone. Sepsis requiring double J placement 7 months ago. New admission with double J malfunction (obstruction), a nephrostomy was placed. Very symptomatic.