Abstract: Objective: To develop an assessing scale for paternal role adaptation of fathers of preterm infants discharged from the NICU, and test its reliability and validity, providing a tool for evaluating the level of paternal role adaptation of discharged preterm infants. Methods: Guided by Meleis' Transition Theory, the draft of the scale was formed through literature review, qualitative interviews, and expert consultation. From September 2023 to April 2024, a questionnaire survey was conducted among 304 fathers of preterm infants conveniently recruited from the outpatient department of a tertiary grade A children's hospital in Chongqing. Item analysis was used to screen items, and the scale was further evaluated for reliability and validity. Results: The scale consisted of three dimensions: role cognition, knowledge and skills, and emotional and social support, with a total of 18 items. Confirmatory factor analysis showed that all model fitting indices reached acceptable levels. The item-level content validity index ranged from 0.800 to 1.000, and the scale-level content validity index was 0.965. The Cronbach's α coefficient of the scale was 0.940, and the split-half reliability was 0.901. Conclusion: The paternal role adaptation scale for NICU preterm infants' fathers has good reliability and validity. It can reflect the degree of role adaptation of fathers of preterm infants, and is applicable as an evaluation tool for measuring their paternal role adaptation level.

Key words: preterm infants; fathers; role adaptation; scale development; reliability; validity