Background and aim <p>South Korea revised its nurse staffing grade indicators in 2018 by changing the evaluation criteria from nurse-to-bed ratios to nurse-to-patient ratios, enabling hospitals to qualify for higher inpatient reimbursement rates. Beginning in 2020, during the peak of the COVID-19 pandemic, this policy was extended to all medical institutions except tertiary hospitals. This study investigated whether the revised indicators resulted in actual increases in nurse employment and examined their implications for addressing persistent nurse shortages during the COVID-19 pandemic in South Korea.</p> Methods <p>A longitudinal study analyzed data from 1,152 hospitals between 2019 and 2023, examining changes in nurse staffing levels and related indicators. The data were analyzed using descriptive statistics, chi-square tests, and generalized estimating equations.</p> Results <p>By 2023, 35.9% of hospitals achieved the highest nurse-to-patient ratio grade (Grade 1), compared to only 3.0% under the nurse-to-bed ratio indicator. However, 20.8% of hospitals showed improved nurse-to-patient ratios without corresponding changes in nurse-to-bed ratios, suggesting that the improvements may be due to shifts in patient numbers rather than actual increases in nurse employment. The relative risk (RR) of improving nurse-to-bed ratio grades during the pandemic was less than 1 (RR 0.88–0.94), indicating a worsening trend, while nurse-to-patient ratio grades improved (RR 1.19–1.22).</p> Conclusion <p>The revised indicators improved apparent compliance, but this change was driven by metric changes and reduced patient admissions, not a substantive reinforcement of staffing levels. Without sufficient recruitment, rising post-pandemic patient volumes may exacerbate nurse workloads and compromise care quality. Policymakers should closely evaluate the outcomes of staffing policies and ensure adequate incentives for nurse recruitment.</p>