[Detection of mental health problems in childhood]

To validate the Report Questionnaire for children (RQC) in order to estimate the prevalence of childhood psychiatric disorders in Mexico.

The RQC was applied by random selection to parents of children in a specialized care service, in a general practice setting and in schools, during an urban household survey within the National Mental Health Survey (NMHS) conducted in 1988. The sample size of adults participating in the NMHS was 2,025. Fifty-two percent (1,068) reported having a child between 3 to 12 years old living in the household. The data collection instrument was applied to the oldest children in that range. The weighted mean was used for analysis and the unbiased prevalence was estimated using the formula proposed by Rogan and Gladen; predictive values were computed using a Bayesian expression.

The estimated prevalence of mental health disorders for children aged 3 to 12 years old was between 16.4% and 20.7%. The Positive Predictive Value of the instrument ranged between 46.6% and 76.1%, depending of the cut-off points: one or more positive items in the questionnaire or two or more. The Negative Predictive Value (NPV) ranged between 91.6% and 99.2%.

The estimates are very similar to those reported in different countries and the NPV supports the reliability of the estimates and the potential uses of the instrument for the early detection of childhood psychiatric disorders.