OBJECTIVE: To inform primary care screening and preventive intervention efforts, the authors examined the screening efficiency of the parent version of the Strengths and Difficulties Questionnaire (SDQP4-16) for persistent disorders relative to transient disorders and its capacity to distinguish between the two. METHODS: Persistence and transience in preschool-onset psychiatric disorders were identified by using data from a large population-based cohort study in Norwegian children initially assessed at age 4 and followed up at age 6 (n = 1038). Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnoses at both time points were assigned by using the Preschool Age Psychiatric Assessment Interview, against which the SDQP4-16 was compared through receiver operating characteristics analysis. RESULTS: The screening efficiency for persistent disorders exceeded that for transient disorders with a specificity of 86.1%, a sensitivity of 79.3%, and an area under the curve value of 0.85. The SDQP4-16 was able to discriminate persistent disorders from transient disorders at an area under the curve value of 0.71. At the selected cutoff of 10, the negative predictive value was 99.6%, whereas the positive predictive value was 9.5%, partly due to the low prevalence (1.8%) of persistent disorders. CONCLUSIONS: The SDQP4-16 is a sensitive tool for detecting persistent psychiatric disorders in young children. However, a large proportion of positive screens are nonpersistent cases, as indicated by the high false-positive rate. Thus, the clinical utility of the SDQP4-16 in primary care screening for persistent disorders is uncertain, particularly in samples in which the rate of psychiatric disorders is low.