“…Factor analyses of the IBQ have yielded overarching factors related to Positive Affectivity and Negative Affectivity (Kochanska, Coy, Tjebkes, & Husarek, 1998;Rothbart, 1986) extracted for mothers' (and fathers') ratings of infants from 3 to 12 months. Smiling and laughter, duration of orienting, and soothability generally comprise the Positive Affectivity factor; distress to limitations and fear comprise the Negative Affectivity factor; and activity level loads on either or both factors depending on the sample being analyzed (Carranza Carnicero, P erez L opez, Salinas-Gonz alez, & Mart ınez-Fuentes, 2000;Kochanska et al, 1998). Much of contemporary research concerning infant temperament is based on Rothbart's theory and IBQ measures of the structure of infant temperament (Carranza Carnicero et al, 2000;Gartstein, Knyazev, & Slobodskaya, 2005;Gartstein & Rothbart, 2003;Kochanska et al, 1998;Putnam, Gartstein, & Rothbart, 2006;Putnam, Rothbart, & Gartstein, 2008;Rothbart, 2011).…”