Overview
The B-CAP is a measure of recent paranoid thoughts in adolescents.Scoring & Interpretation
The Bird Checklist of Adolescent Paranoia is an 18 item self-report measure of paranoid thoughts in adolescents. Respondents rate the frequency with which they have had each thought in the last two weeks, from Never (0) to All the time (5). Item scores are summed to give an overall score. Higher scores indicate increased paranoia.Psychometric Properties
Internal Consistency
Item response theory indicated consistency was excellent within the measure, with alpha = .90.
Test-Retest Reliability
Factor Structure
The authors treated the questionnaire as a unidimensional measure of paranoia. Item response theory modelling indicated that this was an appropriate way to interpret the measure. Exploratory and confirmatory factor analyses conducted by Schlier and colleagues then indicated a three-factor structure, consisting of physical threat, social threat and power threat - but these three factors were strongly correlated with each other, indicating a larger scale score can also be calculated.
Validity
Schlier et al., (2024), reported high correlations between subscale scores on the BCAP and Revised-Green et al.’s Paranoid Thoughts Scale (R-GPTS). Schlier and colleagues found very high correlations between BCAP scores and self-reported experiences of bullying on the Gatehouse Bullying Scale (r = .69 - .79), which could indicate overlap in the constructs being measured.
Measurement Invariance
No differential item functioning was identified across the age range tested (11 to 17 years), nor across gender or clinical vs non-clinical groups.