Effect size is crucial in nursing research for several reasons: 1. Clinical Significance: While a study may show a statistically significant result, the actual impact on patient care may be minimal. Effect size helps in understanding the real-world significance of the findings. 2. Comparison Across Studies: Effect sizes allow for comparisons across different studies and interventions, making it easier to understand which practices are most effective. 3. Evidence-Based Practice: Nurses can make more informed decisions about implementing new protocols or treatments by considering the effect size, which aligns with the principles of evidence-based practice.