Assessing the Psychometric Properties of the Functional Analytic Psychotherapy Intimacy Scale (FAPIS) in a Spanish-Speaking Population

Intimacy is an interpersonal repertoire related to physical and behavioral health indicators. Functional analytic psychotherapy (FAP) is a behavioral intervention that has demonstrated utility in improving intimacy repertoires, particularly in experimental single-case designs. The FAP Intimacy Scale (FAPIS) was developed with the aim of using a theoretically sound measure to evaluate FAP effects on a large scale. This study sought to culturally adapt and validate the FAPIS for Spanish-speaking populations. A total sample of 509 Spanish-speaking participants completed the survey. Exploratory and confirmatory factor analyses were conducted to examine FAPIS psychometric properties. A network analysis was also performed to assess the relation among scale factors. As expected, the FAPIS Spanish version demonstrated a good fit, meeting the same three-factor structure as the original version. Network loading along three factors was also found, and item 3 was identified as the most central item in the scale. Low and negative correlations among FAPIS, experiential avoidance, emotional sensitivity, and social impact were found. Findings showed that FAPIS is a valid and reliable measure for assessing intimacy in Spanish-speaking populations.