Infection Control Knowledge, Job Stress, and Self-Efficacy in Relation to Infection Control Performance Among Intensive Care Unit Registered Nurses: A Descriptive Cross-Sectional Study

Background/Objectives: Healthcare-associated infections remain a critical patient-safety concern in intensive care units (ICUs), where invasive procedures and immunocompromised patients elevate infection risk. Infection control knowledge, job stress, and self-efficacy have each been linked to infection control performance, but few studies have examined these factors simultaneously among ICU registered nurses (RNs). This study aimed to investigate ICU RNs’ infection control knowledge, infection control job stress, self-efficacy, and infection control performance, and to identify factors associated with infection control performance. Methods: This descriptive cross-sectional study surveyed 191 ICU RNs (of 219 recruited) with ≥6 months of ICU experience at two tertiary hospitals in the Republic of Korea (December 2024–January 2025) using structured, validated questionnaires. Data were analyzed with descriptive statistics, independent t-tests, one-way ANOVA (Scheffé/Games–Howell post hoc), Pearson correlation, and hierarchical multiple regression (SPSS 22.0). Results: Mean scores were 19.16 ± 1.07 (of 20) for infection control knowledge, 3.23 ± 0.67 (of 5) for infection control job stress, 3.62 ± 0.53 (of 5) for self-efficacy, and 4.82 ± 0.26 (of 5) for infection control performance. Infection control performance was positively correlated with knowledge (r = 0.151, p = 0.037), job stress (r = 0.161, p = 0.026), and self-efficacy (r = 0.178, p = 0.014). Hierarchical regression showed that current ICU department (surgical, cardiac, emergency, trauma, and general ICU vs. internal medicine ICU as reference), infection control job stress (β = 0.188, p = 0.008), and self-efficacy (β = 0.157, p = 0.022) significantly predicted infection control performance, together explaining 17.4% of the variance (F = 5.995, p < 0.001); infection control knowledge was a nominally significant predictor in this model (β = 0.164, p = 0.016), but this association was not robust to sensitivity analyses (Spearman ρ = 0.034, p = 0.636; heteroscedasticity-robust regression p = 0.095) or to a covariate-adjusted robustness check (p = 0.091), and should be interpreted with caution. Conclusions: Infection control job stress, self-efficacy, and current department were robustly associated with infection control performance among ICU RNs across all sensitivity analyses; infection control knowledge showed a comparatively weaker, fragile association that did not survive rank-based, heteroscedasticity-robust, or covariate-adjusted sensitivity checks. Effect sizes were small to moderate overall, and the final model explained only 17.4% of variance. Department-tailored education and organizational support strategies—channeling job stress constructively and strengthening self-efficacy through hands-on training and mentoring—may help sustain and improve infection control performance; recommendations regarding knowledge-related training should be treated as preliminary given the fragility of this association.