2011 Volume 52 Issue 1 Pages 32-42
Investigations of factors relating to recovery from childhood stuttering are usually based on univariate analysis. Due to this, these factors may not be properly understood, because the relationship between a specific characteristic and recovery from stuttering may be confounded by other factors, or because the relationship between a characteristic and recovery may differ according to whether the subject possesses another factor concurrently. We conducted a longitudinal study of stuttering children who received treatment at stuttering treatment facilities and performed a multivariate analysis by sex and time from onset. We examined the associations between recovery and pre-treatment characteristics by following 97 stuttering children (average age at first consultation at a research institute, 55.7 months; range, 24-111 months) who received stuttering treatment from speech-language-hearing therapists in 14 stuttering treatment facilities. The average time from onset until recovery or end of observation was 36.0 months (range, 5-83 months). Characteristics associated with recovery from stuttering on univariate analysis were simultaneously entered into a proportional hazards model. In this model, stuttering developmental phase was identified as a factor independently related to recovery on analysis of all subjects and analysis by sex. On analysis by time from onset, pre-treatment characteristics were associated with recovery only in the group that received consultations at a stuttering treatment facility within 24 months of onset. An onset age of 24 months or earlier, female sex and a stuttering developmental phase of 1 were found to be associated with a high recovery rate in a mutually independent manner. The period when predictive factors of stuttering recovery can be observed is within 24 months of onset; prognosis for stuttering treatment begun within this time frame can be predicted based on onset age, sex, and pre-treatment developmental phase.
