BACKGROUND: phonological therapy. AIM: to evaluate the effectiveness of three different therapy models regarding changes in the phonological system of subjects with different phonological disorder (PD) severity levels. METHOD: the research group was composed by 66 subjects, 43 males and 23 females, with ages between 4:4 and 8:2 years, who were part of a school clinic database. All subjects were evaluated, before and after a period of 15 to 25 sessions of phonological therapy, using the Child's Phonological Assessment. Based on this assessment, the severity level of the PD was determined using the Percentage Consonants Correct - PCC, and by calculating the number of Non-Acquired Segments -NAS and the percentage of Acquired Segments (AS) after treatment. The subjects were treated using the following approaches: ABAB-Withdrawal and Multiple Probes, Modified Maximum Opposition and Modified Cycles Models. For the statistical analysis the T-Test was used with a significance level of 5%. RESULTS: the statistical analysis indicated an increase in the PCC and in the percentage of AS, as well as a reduction in the number of NAS for all groups. These results were statistically significant for the majority of the groups. CONCLUSION: the results indicate that the three therapy approaches were effective in the treatment of children with PD, and were effective in treating different severity levels. Besides that, most of the changes occurred in the phonological system of the groups with more severe PD.
Phonological Disorders; Speech; Speech Therapy; Speech Disorder