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Language evaluation protocol for children aged 2 months to 23 months: analysis of sensitivity and specificity.

PURPOSE
To establish cutoff points for the analysis of the Behavior Observation Form (BOF) of children in the ages of 2 to 23 months and evaluate the sensitivity and specificity by age group and domains (Emission, Reception, and Cognitive Aspects of Language).


METHODS
The sample consisted of 752 children who underwent BOF. Each child was classified as having appropriate language development for the age or having possible risk of language impairment. Performance Indicators (PI) were calculated in each domain as well as the overall PI in all domains. The values for sensitivity and specificity were also calculated. The cutoff points for possible risk of language impairment for each domain and each age group were obtained using the receiver operating characteristics curve.


RESULTS
The results of the study revealed that one-third of the assessed children have a risk of language impairment in the first two years of life. The analysis of BOF showed high sensitivity (>90%) in all categories and in all age groups; however, the chance of false-positive results was higher than 20% in the majority of aspects evaluated. It was possible to establish the cutoff points for all categories and age groups with good correlation between sensitivity and specificity, except for the age group of 2 to 6 months.


CONCLUSION
This study provides important contributions to the discussion on the evaluation of the language development of children younger than 2 years.