Background: An international reference measurement laboratory network for creatinine (Cr) is lacking; therefore, Korea developed an independent evaluation and certification system. The in vitro diagnostics (IVD) certification program, launched in 2017, formed part of a broader Cr standardization initiative intended to enhance accuracy at the manufacturing stage. Methods: The program was designed to evaluate analytical systems, including all reagent lots, calibrators, and instrument models, twice annually. Bias, imprecision, total error (TE), and linearity were evaluated based on established acceptance criteria. A post-certification process allows submission for a second challenge and validation of corrective actions. Results: Between 2017 and 2023, 489 analytical systems were evaluated. Average acceptance rates for bias, imprecision, TE, and linearity were 70.8%, 95.9%, 87.7%, and 87.8%, respectively. The lowest acceptance rate for bias evaluation was 8.7% for the kinetic Jaffe method without compensation in 2018. Over the 7-year period, the mean absolute percentage bias (absBias%), coefficient of variation (CV), and TE were 4.62%, 1.37%,and 7.29%, respectively. The highest absBias% (7.94%) was observed in the 0.0 ≤ Cr < 1.0target value range. Since 2019, a consistent reduction in absBias% has been observed. Conclusions This program is a pioneering response to the absence of a global certification program for Cr assays. It offers significant advantages, including comprehensive evaluations, fee-free participation, and a robust post-certification process. Continuous participation and improvement efforts by manufacturers have contributed to enhanced accuracy in Cr assays.

Background: Aortic valve sclerosis (AVS) shares risk factors with atherosclerosis. However, the relationship between AVS progression with cardiovascular (CV) risk has not been researched. This study investigates CV outcomes according to progression of AVS. Methods: This study included 2,901 patients with AVS (irregular leaflet thickening and peak aortic jet veloc‑ ity < 2 m/sec) who underwent serial echocardiograms at least 1 year apart during 2011–2020. The primary outcome was defined as CV death, myocardial infarction, stroke, or revascularization. Results: During a median follow-up period of 3.9 years, 439 of 2,901 AVS patients (15.1%) progressed to mild or greater aortic stenosis. Patients with progression were older and more likely to have atrial fibrillation than those without. In a stepwise regression, age (odds ratio [OR] per 1-year increase, 1.04; 95% confidence interval [CI], 1.01– 1.07), peripheral artery disease (OR, 9.07; 95% CI, 3.12–26.4), and left ventricular mass index (OR per 1-g/m 2 increase, 1.01; 95% CI, 1.00–1.02) were associated with AVS progression. Over a median of 6.3 years, the primary outcome occurred in 858 of 2,901 patients (29.6%). Patients with progression had higher frequency of CV death, myocardial infarction, stroke, or revascularization than those without progression (P < 0.0001). In Cox proportional hazards regres‑ sion, AVS progression (hazard ratio, 1.33; 95% CI, 1.10–1.61) was a significant determinant of CV mortality. Conclusions The progression to aortic stenosis in AVS patients is an independent risk factor for CV mortality. These findings suggest that patients with AVS progression may benefit from stricter CV risk monitoring.

Background: Aortic valve sclerosis (AVS) shares risk factors with atherosclerosis. However, the relationship between AVS progression with cardiovascular (CV) risk has not been researched. This study investigates CV outcomes according to progression of AVS. Methods: This study included 2,901 patients with AVS (irregular leaflet thickening and peak aortic jet veloc‑ ity < 2 m/sec) who underwent serial echocardiograms at least 1 year apart during 2011–2020. The primary outcome was defined as CV death, myocardial infarction, stroke, or revascularization. Results: During a median follow-up period of 3.9 years, 439 of 2,901 AVS patients (15.1%) progressed to mild or greater aortic stenosis. Patients with progression were older and more likely to have atrial fibrillation than those without. In a stepwise regression, age (odds ratio [OR] per 1-year increase, 1.04; 95% confidence interval [CI], 1.01– 1.07), peripheral artery disease (OR, 9.07; 95% CI, 3.12–26.4), and left ventricular mass index (OR per 1-g/m 2 increase, 1.01; 95% CI, 1.00–1.02) were associated with AVS progression. Over a median of 6.3 years, the primary outcome occurred in 858 of 2,901 patients (29.6%). Patients with progression had higher frequency of CV death, myocardial infarction, stroke, or revascularization than those without progression (P < 0.0001). In Cox proportional hazards regres‑ sion, AVS progression (hazard ratio, 1.33; 95% CI, 1.10–1.61) was a significant determinant of CV mortality. Conclusions The progression to aortic stenosis in AVS patients is an independent risk factor for CV mortality. These findings suggest that patients with AVS progression may benefit from stricter CV risk monitoring.

Background: Aortic valve sclerosis (AVS) shares risk factors with atherosclerosis. However, the relationship between AVS progression with cardiovascular (CV) risk has not been researched. This study investigates CV outcomes according to progression of AVS. Methods: This study included 2,901 patients with AVS (irregular leaflet thickening and peak aortic jet veloc‑ ity < 2 m/sec) who underwent serial echocardiograms at least 1 year apart during 2011–2020. The primary outcome was defined as CV death, myocardial infarction, stroke, or revascularization. Results: During a median follow-up period of 3.9 years, 439 of 2,901 AVS patients (15.1%) progressed to mild or greater aortic stenosis. Patients with progression were older and more likely to have atrial fibrillation than those without. In a stepwise regression, age (odds ratio [OR] per 1-year increase, 1.04; 95% confidence interval [CI], 1.01– 1.07), peripheral artery disease (OR, 9.07; 95% CI, 3.12–26.4), and left ventricular mass index (OR per 1-g/m 2 increase, 1.01; 95% CI, 1.00–1.02) were associated with AVS progression. Over a median of 6.3 years, the primary outcome occurred in 858 of 2,901 patients (29.6%). Patients with progression had higher frequency of CV death, myocardial infarction, stroke, or revascularization than those without progression (P < 0.0001). In Cox proportional hazards regres‑ sion, AVS progression (hazard ratio, 1.33; 95% CI, 1.10–1.61) was a significant determinant of CV mortality. Conclusions The progression to aortic stenosis in AVS patients is an independent risk factor for CV mortality. These findings suggest that patients with AVS progression may benefit from stricter CV risk monitoring.