Conners' Teacher Rating Scale has limited ability to predict DSM-IV ADHD in referred schoolchildren.

QUESTION Question: What is the predictive validity of the revised Conners' Teacher Rating Scale (CTRS-R) for identifying children with attention defi cit hyperactivity disorder (ADHD) in a clinical sample compared with the Telephone Teacher Interview (TTI-IV)? Patients: 1038 children aged 6–12 years referred for assessment of attention, learning and behavioural problems to a paediatric clinic (mean age 8.8 years, 75.5% male). Children on psychotropic medications other than stimulants, attending full time treatment programmes, with premature birth, history of serious head trauma, a chronic medical condition, recent history of abuse or who were adopted were excluded. Test: The CTRS-R, a 59 item teacher report form used to identify children with ADHD and associated behavioural dif-fi culties. This was given to teachers by parents and completed before clinical assessment. Three subscales (L, M and N) were used to identify DSM-IV subtypes (inattentive, hyperactive/ impulsive and combined, respectively). Scores were converted to T scores, scaled for age and gender, and a score of 50 taken as the mean score for the population. A cutoff T score of ≥60 was used to detect the presence of ADHD subtypes; the effects of varying this cutoff were investigated. Diagnostic standard: The TTI for DSM-IV or fi nal clinical diagnosis. The TTI-IV is a semi-structured telephone interview used to obtain a teacher's description of child behaviour in the classroom and schoolyard. The TTI-IV was measured before clinical assessment, and all interviewers and assessors had no knowledge of either test or diagnostic standard scores until all diagnostic measures and interviews were complete. Outcomes: Sensitivity, specifi city, positive and negative likelihood ratios, positive and negative post-test probabilities. MAIN RESULTS Using the teacher reported diagnostic standard, 53.7% of children were classifi ed as meeting DSM-IV criteria for ADHD, 13.9% for oppositional defi ant disorder and 4% for conduct disorder. T scores of 60 or more (1 SD above the population mean) on all CTRS-R subscales showed good sensitivity but low specifi city for detecting TTI-IV assessed inattentive symptoms (sensitivity 93%, specifi city 39%), hyperactive–impulsive symptoms (sensitivity 91%, spec-ifi city 53%) and combined symptoms (sensitivity 94%, specifi city 32%). For detecting clinical ADHD, sensitivities were also high for the inattentive subtype (sensitivity 85%, specifi city 46%) and combined subtype (sensitivity 82%, specifi city 48%) but lower for hyperactive–impulsive sub-type (sensitivity 69%, specifi city 60%). Increasing the cutoff value for the T score resulted in increased specifi city for diagnosing ADHD subtypes …