Predictive validity of the K-SADS-PL 2009 version in school-aged and adolescent outpatients
Sammanfattning
Background: The schedule for affective disorders and schizophrenia for school-age children (K-SADS)
is one of the most commonly used standardized diagnostic interviews in child and adolescent psychiatry.
Validity studies are scarce, and limited to concurrent validity with other measures and clinical
diagnoses.
Aims: To evaluate the K-SADS interview in an outpatient child and adolescent psychiatry (CAP) setting
with a Longitudinal Expert All Data (LEAD) procedure.
Methods: CAP residents performed a K-SADS-PL interview with the revised 2009 version containing
the new PDD section on 239 clinically referred outpatients of 6–17 years old and their parent(s). A consensus
LEAD diagnosis by two senior clinicians 1.2 (SD¼ 0.6) years later was based on clinical records
including the K-SADS and subsequent information from further assessments, information from teachers
and other informants, outcome of treatment, and at least three visits after the K-SADS.
Results: Predictive validity for K-SADS vs LEAD diagnoses were good-to-excellent for broader categories
of anxiety disorders (j ¼ 0.94), depressive (j ¼ 0.91), behavioural (j ¼ 0.91) and tic (j ¼ 0.81) disorders,
good for ADHD (j ¼ 0.80), and good-to-moderate for autism spectrum disorders (j ¼ 0.62).
Bipolar, psychotic, and eating disorders were too few to be analysed.
Conclusion: The K-SADS diagnoses elicited from an interview with the child and one from parents on
one occasion have an excellent validity for most major child psychiatric disorders. ADHD can be reliably
diagnosed at one visit, but clinicians need to stay alert for possible undiagnosed ADHD.
Diagnosing autism with K-SADS-PL 2009 version at one visit is not advisable.