Informants are not all equal: predictors and correlates of clinician judgments about caregiver and youth credibility.

OBJECTIVE: The objectives of this study were to examine how often clinicians judged youths or caregivers to not be credible informants, to identify the associated features of youth or caregiver credibility, and to examine credibility's impact on the validity of mood and behavior checklists.
BACKGROUND: Clinicians often have the experience of talking to a parent or a youth and judging that the credibility of the information offered is unusually poor. Little is known about the correlates of poor credibility or about the extent to which credibility changes the validity of commonly used checklists.
METHODS: Interviewers rated the credibility of 646 youths aged 5-18 and their primary caregivers after completing a Kiddie Schedule for Affective Disorders and Schizophrenia. Ratings and diagnoses were blind to the behavior checklists completed by caregivers, youths, and teachers. A subset of youths also had intelligent quotient tests and behavioral observations available.
RESULTS: Caregivers were perceived as more credible on average than youths, though this dropped sharply with adolescents. Caregiver credibility was higher for better functioning families, more credible youths, younger youths, and more educated caregivers; it was unrelated to caregiver mood symptoms or being the mother. Youth credibility was strongly connected to age, cognitive ability, caregiver credibility, and independent observations of youth behavior. Credibility ratings markedly altered the validity of checklists compared with interview ratings, diagnoses, or cross-informant criteria.
CONCLUSION: Clinicians' judgments about informant credibility are associated with different characteristics for youths versus caregivers, though youth age is important to both. Credibility affects the validity of information from checklists measured against several different independent criteria.