Screening Accuracy of the Parent-Report Preschool Strengths and Difficulties Questionnaire in Primary Care

OBJECTIVE : To evaluate the screening test accuracy and reliability of the parent-report preschool Strengths and Difficulties Questionnaire (P-SDQ) in primary care settings. M ETHODS : Children 24 to 48 months were recruited at scheduled primary care visits in Toronto, Canada. Parents completed the P-SDQ at baseline, 2, and 12 weeks. At 12 weeks, parents were invited to a semistructured diagnostic phone interview, the Preschool Age Psychiatric Assessment (PAPA). Criterion validity between baseline P-SDQ scores (Total Difficulties Score [TDS], internalizing and externalizing subscale) and Diagnostic and Statistical Manual, 5th edition diagnoses on PAPA was evaluated using area under the curve (AUC) and calculating screening test properties (sensitivity and specificity). Test-retest reliability at baseline and 2 weeks was evaluated using intraclass correlation coefficient. R ESULTS : A total of 183 children were enrolled, mean age 39.3 (SD 7.4) months, 46.4% male, 120 (66%) completed P-SDQ at 2 weeks, 107 (58%) completed PAPA at 12 weeks. Of those with a PAPA, 26 (24%) had any psychiatric diagnosis, 17 (16%) had internalizing disorders and 4 (4%) had externalizing disorders. TDS identified any diagnosis with AUC = 0.67 (95% confidence intervals (CI): 0.55, 0.79); internalizing subscale identified internalizing disorders with AUC = 0.61 (95% CI: 0.47, 0.74); externalizing subscale identified externalizing disorders with AUC = 0.77 (95% CI: 0.60, 0.94). Sensitivity and specificity, and test-retest reliability were satisfactory for TDS and externalizing subscale, and less satisfactory for the internalizing subscale. C ONCLUSIONS : The externalizing subscale has sufficient accuracy and reliability to identify children aged 2 to 4 years at risk for attention deficit/hyperactivity disorder and disruptive behavior disorders in primary care.