In the realm of nursing, a theory is a systematic framework that provides perspective and guidance for the practice of nursing. The definition of nursing theory is multifaceted, encompassing its role as a foundational framework guiding professional nursing practice toward the restoration of patients’ desired well-being and health. Furthermore, nursing theory is recognized as indispensable for elevating the caliber of nursing practice, informing educational methodologies, fostering research endeavors, and garnering due societal recognition as a profession.

The fourfold functions of nursing theory—description, explanation, prediction, and control—are paramount in systematically organizing the intricate relationships among phenomena prevalent in nursing situations. While addressing relatively specific and concrete phenomena, the scope of nursing theories varies, delineated by the specificity of the concepts and propositions integral to the theory. Classification into grand theories, middle-range theories, and micro theories is contingent upon the scope of applicability. Furthermore, theories can be categorized based on their level of development, encompassing descriptive, explanatory, and predictive theories. The utility of nursing theories is assessed by evaluating aspects such as the validity of the development process, internal consistency, clarity, verifiability, empirical adequacy, and practical relevance. Since the era of Florence Nightingale, various nursing theories have emerged. Nurses, in their pursuit of specialized nursing practice, acquire and apply this theoretical foundation, contributing to the evolving body of nursing knowledge.

• Fawcett, J. (1990). Understanding the nursing model: Analysis and evaluation (Kojima, N., Trans.). Igaku-Shoin.
• Tomey, A. M., & Alligood, M. R. (2004). Nursing theorists and their achievements (3rd ed.; Tsuru, N., Trans.). Igaku-Shoin.
• Torres, G. (1992). Nursing theory and nursing process (Yokoo, K., Tamura, Y., & Takada, S., Trans.). Igaku-Shoin.