This research investigated whether stuttering treatment delivered in English resulted in reductions in stuttering in English and Mandarin bilingual Singaporean speakers. After English-only treatment, stuttering reductions were found to generalize to Mandarin. Stuttering reductions were significantly higher in English compared to Mandarin at 4 weeks post-IP, but there was no significant difference in the stuttering reductions between languages at the end of IP and at 12 weeks post-IP. The results of this study show that stuttering reductions can be achieved in two languages following treatment in one language only.
Lim, Valerie P.C., Lincoln, Michelle, Onslow, Mark, and Chan, Yiong Huak. (2014). English-only treatment of bilingual speakers who stutter: Generalization of treatment effects from English to Mandarin. International Journal of Speech-Language Pathology, doi: 10.3109/17549507.2014.979874