Advancing differential susceptibility research: Development and validation of the temperamental sensitivity Q-scale.

Temperamental sensitivity (TS), which is a correlated suite of traits reflecting a lower threshold of environmental stimulation and heightened responsivity to a range of environmental contexts, is an empirically documented susceptibility factor that increases children's plasticity to supportive and harsh family environments. To expand the limited options for assessing TS, this article tested the psychometric properties of a new Q-set measure (i.e., TS Q-scale) derived from the California Child Q-Set (CCQ-Set) and completed by experimenters. Participants in Study 1 consisted of 243 mothers, their partners, and their preschool children ( = 4.60 years; 56% girls; 54% Black or multiracial; 16% Latinx). For Study 2, participants included 201 mothers and their young children ( = 2.25 years; 44% girls; 63% Black or multiracial; 11% Latinx). Both longitudinal studies utilized multimethod, multiinformant measurement batteries. The TS Q-scale evidenced satisfactory internal consistencies across both studies. Support for the convergent and discriminant validity in Study 1 was evident in its large, unique, and significantly stronger association with a standard, more extensive, observational assessment of TS when compared with conventional dimensions of temperament. In each study, the TS Q-scale significantly moderated the association between family functioning and latent change analyses of children's functioning for most of the forms of child adjustment. Supporting its predictive validity as a differential susceptibility attribute, children with higher scores on the TS Q-scale exhibited substantially better functioning than their peers in supportive socialization contexts and considerably worse functioning in harsh rearing conditions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).