Further validity evidence of the Behavioral Inhibition Observation System (BIOS).

BACKGROUND The Behavioral Inhibition Observation System (BIOS) is a brief clinician-report scale for detecting behavioral inhibition (BI) from direct observation. This study aims to compare the validity coefficients obtained in the natural context of use of the BIOS (i.e., a clinical situation) with those obtained using the BIOS after standardized observation. METHOD The participants were 74 randomly selected preschool children who were exposed to systematic observation. RESULTS The results indicate excellent internal consistency (α = .91) and moderate to good inter-rater reliability for all items (ICC from .55 to .88). The correlations with observational measures of BI ranged from .40 to .70, and were mostly equivalent to those of the previous study. The correlations with parents', teachers', and clinicians' measures of BI and related constructs ranged from .30 to .60, and were also equivalent to those obtained in the natural context of use of the BIOS (i.e., clinical situation). CONCLUSIONS The validity coefficients obtained with the BIOS in a non-structured natural observation are mostly equivalent to those obtained in an experimental situation, thus supporting that the BIOS is a cost-efficient instrument for measuring BI from observation in a clinical situation.