Prevalence and Capacity Building in Brazil

Background:  In Brazil, a single study reporting ASD prevalence in the childhood has estimated a rate of 0.3%, which is probably an underestimate due to methodological limitations. This research also showed that most of the positive cases had no previous diagnosis of ASD, and it is known that early identification is one of the main predictors of functional outcome and social adaptation in patients with ASD.

Objectives:  (1) to present results from a recent prevalence study conducted in four Brazilian regions; (2) to evaluate the impact of a pilot training program on ASD identification offered to professionals from the Public Health system.

Methods:  Study 1 - Design: Multicenter cross-sectional-study. Sample/Settings: 1,715 students (aged 6-16) from 2nd-6th grade enrolled in elementary public school, from four towns from four out of five Brazilian regions, were randomly selected. Instruments: (i) screening ASD: subscale of the K-SADS-PL; (iii) Estimated IQ: two subtests (Vocabulary and Blocks) of the WISC-III; (iii) Service use: structured questionnaire developed by our research team. 

Study 2 – Participants/training program: the training program offered to 20 primary care providers (most pediatricians) consisted of five three-hour weekly training sessions comprising two hours of lectures and one-hour case discussion. The main themes delivered by ASD experts were: epidemiology; ASD symptoms and early signs; and evidence-based treatments. The main objective of the training was to improve detection of suspected cases of ASD and to refer them to the single local specialized unit. Assessments: (1) to measure the knowledge acquisition, a structured questionnaire comprising of 13 multiple-choice questions and vignettes of clinical ASD cases was developed by our research team (applied before and immediately after the training). (2) to identify changes in the clinical practice, we compared data on the amount and profile of suspected ASD cases referred for these professionals to the specialized unit, four months before and after the conclusion of the training. 

Results:  Study 1: the estimated prevalence rate was 1%. Among the positive cases, (a) 62.5 % were male; (b) 12% had average/normal IQ; and (c) only 56.3% had been seen by a health specialist (psychologist/neurologist/psychiatrist) in the previous year, and 37.5% had received specialized educational support in the same period. 

Study 2: health providers significantly improved their ASD knowledge after training in comparison with pre-training [mean score 6.73 vs 9.18 (p<0.01)]. Clinical practice also changed: they had referred 6 times as many suspected cases of ASD to a specialized mental health service four months after the training program in comparison with the previous four months.

Conclusions:  The prevalence of ASD identified in this study is in accordance with international rates. Only a small proportion of youth with ASD had been seen by a health/educational specialist in the previous year. The pilot training-model presented seems a promising, feasible and inexpensive way to improve early identification of ASD in the primary care system.