Delayed auditory feedback in the treatment of stuttering: clients as consumers

To investigate the effect of repeated exposure to delayed auditory feedback (DAF) during a 3-month period outside a clinical environment and with only minimal clinical guidance on speech fluency in people who stutter.

A pretest-post-test design was used with repeated exposure to DAF during 3 months as the independent variable. Nine stuttering individuals aged between 18 and 45 years served as subjects. Videotaped samples from different speech tasks were collected before and after 3 months' exposure to DAF, each time under two conditions: first during non-altered feedback (NAF) and subsequently during DAF.

Before the repeated exposure to DAF, the percentage of stuttered words was significantly higher during NAF than during DAF. After 3 months' exposure to DAF, the percentage of stuttered words during NAF had dropped to a non-significant level in comparison with the DAF condition. Comparison of the percentage of stuttered words during NAF before and after repeated exposure to DAF showed significantly less stuttering after the repeated exposure to DAF. The percentage of stuttered words during DAF was generally somewhat higher, but not significantly so, after the 3 months' repeated exposure to DAF than before the exposure to DAF.

Results confirm that DAF is an effective means of reducing stuttering even when employed as the only treatment approach outside a therapeutic environment. They also suggest that DAF continues to promote fluency when used over a longer period, but also that length of exposure and fluency enhancement are probably not in a linear relationship.