Background <p>The experience of care-related regret among clinical nurses, often stemming from high workloads and the need for quick decision-making, can significantly impact job satisfaction and performance. Recognizing the necessity of measuring this regret, our research aimed to translate and evaluate the psychometric properties of the Care-related Regret Intensity Scale (RIS-10) among Iranian clinical nurses.</p> Methods <p>In this methodological study with a cross-sectional design, a sample of 400 clinical nurses was selected using convenience sampling. The Care-related Regret Intensity Scale (RIS-10) was translated into Persian using a forward-backward translation procedure. This translated version was subsequently utilized for psychometric evaluation, which included an assessment of face validity, content validity, and construct validity through Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). Furthermore, internal consistency and stability reliability were assessed.</p> Results <p>The RIS-10 maintained the meaning of the original English version and was clear, explicit, and understandable for clinical nurses. The content validity was evaluated using CVR and CVI indices, revealing that all items had a CVR above 0.62 and a CVI exceeding 0.79. EFA identified a single latent factor explaining 68.48% of the total variance. The subsequent CFA demonstrated that all items achieved a factor loading of at least 0.3, with goodness-of-fit statistics supporting an excellent fit for the final RIS-10 model. The values of Cronbach’s alpha coefficient and McDonald’s omega were 0.924 and 0.921 for the overall scale, respectively. Additionally, the stability was ICC = 0.913 (95% CI, 0.863–0.941).</p> Conclusion <p>The Persian version of the Care-Related Regret Intensity Scale (RIS-10) is valid and reliable, confirming its suitability for use. It effectively measures the intensity of care-related regret among clinical nurses in Iran.</p> Clinical trial number <p>Not applicable.</p>