An Evaluation of the NANDA International, Inc., Diagnostic Classification Among Spanish Nurses: A Cross-Sectional Study.

: The NANDA International, Inc., (NANDA-I) diagnostic classification is the most widely used standardized nursing language internationally. The EVALUAN-I tool was developed to evaluate the NANDA-I diagnostic classification. The aim was to analyze the use of the NANDA-I diagnostic classification among Spanish nurses and assess its correlation with sociodemographic characteristics. : A cross-sectional study was conducted on a non-probabilistic sample of Spanish nurses working in clinical, management, and academic settings using the EVALUAN-I tool (September 2019-December 2020). The analysis was conducted using R (version 3.6.3, Lavaan package; R Core Team, 2020), with statistical significance set at < 0.05. This study was approved by the Research Ethics Committee (2019-190-1). A total of 483 responses were obtained. There was a correlation between the intensity of use of NANDA-I and its application in practice (polychoric correlation = 0.50; < 0.001). Nurses with a PhD degree considered nursing diagnoses to be less evidence-based ( = 0.037) but more useful ( = 0.035). Academic and research nurses stated that NANDA-I was more useful ( = 0.007), even for exclusive responsibilities ( = 0.034), and that it provided greater significance to diagnoses ( = 0.0012). NANDA-I is the most widely used standardized nursing language in Spain. Nurses' academic qualifications and work environment significantly influence their perceptions and use of NANDA-I. Advanced education fosters a critical yet positive perspective, highlighting a relationship between the intensity of its use, its application in clinical practice, and the nurse's educational background. Tools such as EVALUAN-I promote its integration and evidence-based practice, but challenges remain in improving perceptions, scientific evidence, and visibility in electronic health records to enhance its clinical impact and nursing recognition.