The Slovak Revised Dyadic Adjustment Scale: validation, factor structure, and population norms

The Revised Dyadic Adjustment Scale (RDAS) is a widely used 14-item measure of relationship adjustment. This study aimed to translate, adapt, and validate the Slovak version of the RDAS. The sample consisted of 1,090 individuals (545 couples) from Slovakia. Internal consistency was excellent for the total scale (α = 0.87, ω = 0.87) and subscales (Consensus: α = 0.84; Satisfaction: α = 0.81; Cohesion: α = 0.71). Confirmatory factor analysis supported the original three-factor structure (CFI = 0.925, TLI = 0.908, RMSEA = 0.072, SRMR = 0.053). Construct validity was demonstrated through strong correlations with the Couples Satisfaction Index (r = 0.81, p < 0.001). Mokken scale analysis confirmed adequate scalability (H = 0.375). Population norms are provided; notably, the Slovak sample mean (M = 48.89, SD = 9.43) suggests that United States-derived clinical cutoffs may not be directly applicable to Slovak populations, and percentile-based interpretive guidelines are recommended. Sensitivity analyses correcting for within-couple non-independence (design-effect adjusted CFA and GEE correlations) confirmed robustness of all findings. The Slovak RDAS demonstrates sound psychometric properties and is suitable for assessing dyadic adjustment in Slovak-speaking populations.