Not Anxiety but Self-Regulatory Capacity and Age Predicts Self-Reported Stuttering Severity in Adults Who Stutter...

Previous studies have reported a moderate influence of environmental factors in the aetiology of stuttering. However, psychological and socio-environmental factors in stuttering are often studied independently without exploring their relationships. This makes it difficult to know which factors are most important, especially among adults who stutter (AWS), as much research has focused on the child and adolescents population. The aim of this study was to address these gaps.

After reviewing the literature, a new stuttering scale (PCS-3) was developed to capture the severity of stuttering as experienced by AWS. One hundred and three participants were recruited across five continents from online English-speaking stuttering forums. Participants were between the ages of 18-72. Seventy percent of the sample population were under 30 years old, and 66% were male. Participants with ongoing medical conditions or treatment were excluded. Backward elimination regression was used to identify the most important factors among the tested variables, followed by structural equation modelling to explore their relationship and effects on PCS-3.

The findings suggest that a history of neglect, anxiety, younger adult age and avoidant attachment are risk factors of stuttering severity in this adult sample. However, their effect on stuttering was indirect via a latent self-regulatory capacity (C) construct. Only age had a direct and indirect (via C) small to moderate effect on stuttering. C consistently had a negative moderate to large effect on stuttering across all tested models as measured by the PCS-3. Both age and C accounted for 37% of the variance of stuttering. Implications for research, interventions and limitations are discussed.

What is already known on this subject Previous findings on stuttering have indicated moderate environmental contributions to its aetiology, but little remains known of the specific environmental influences, especially in adulthood. Most psychological research has studied different variables independently without much consideration of their underlying relationships. What this paper adds to existing knowledge Psychosocial variables were found to have an indirect effect on self-reported stuttering in adulthood through the latent construct of self-regulatory capacity (C). Age also accounted for a small to moderate effect. This study adds to the literature by expanding our understanding of the key variables involved in stuttering among adults. What are the potential or actual clinical implications of this work? Interventions can aim to improve C in this population while adapting treatment according to age. The identified psychosocial variables can help identify sub-groups at the highest risk of greater stuttering severity. Clinical implications include a greater understanding and targeting of the factors most likely to improve stuttering for adults who stutter (AWS).