The determination of IQ is essential in the assessment and diagnosis of children. There are multitude of tests, one of the most used are the Wechsler Scales.

Hypothesis: Assessment of IQ is equivalent using the Wechsler Intelligence Scale for Children-Revised (WISCr) and Kaufman inteligence brief test (KBIT).

Subjects Children undergoing treatment at Unit Child and Adolescent Mental Health of Talavera with determination IQ at some point in the intervention: 39 pairings determination of IQ subjects atended: 20 males and 19 females, aged between 4 and 14 years.

Subjects are evaluated with KBIT and WISCr tests.

Design: Quasi-experimental with two conditions.

Independent variables: IQ Total WISCr and age management KBIT (for eight years application of the full test, under this age not full test).

Dependent variable: IQ KBIT.

Calculation of correlation between IQ by non-parametric test. Comparison between groups using non-parametric test for dependent data (sign test). Rejecting null hypothesis for alpha significance P < 0.05.

Partial KBIT; 21 comments, 11 males, 10 females; Spearman r = .714 (P < .001); average estimate of 12.71 points higher in KBIT, Dt 18.07, sign test Z = –2.012 (P < .041).

18 observations, 9 males, 9 females; Spearman r = .739 (P < .001); lower average estimate of 3.44 points in KBIT, Dt 12.43, sign test Z = –.236 (P < .815).

The results support high validity regardless of age management KBIT, although IQ scores obtained before 8 years should be considered with caution. The KBIT has the advantage of its shorter evaluation, however the information obtained from WISCr is wider.

The authors have not supplied their declaration of competing interest.