Stuttering treatment research 1970-2005: II. Systematic review incorporating trial quality assessment of pharmacological approaches

Purpose: To complete a systematic review, incorporating trial quality assessment, of published research about pharmacological treatments for stuttering. Goals included the identification of treatment recommendations and research needs based on the available high-quality evidence. Method: Multiple readers reviewed 31 articles published between 1970 and 2005, using a written data extraction instrument developed as a synthesis of existing standards and recommendations. Articles were then assessed using 5 methodological criteria and 4 outcomes criteria, also developed from previously published recommendations. Results: None of the 31 articles met more than 3 of the 5 methodological criteria (M = 1.74). Four articles provided data to support a claim of short-term improvement in social, emotional, or cognitive variables. One article provided data to show that stuttering frequency was reduced to less than 5%, and 4 additional articles provided data to show that stuttering may have been reduced by at least half. Among the articles that met the trial quality inclusion criterion for the second stage of this review, none provided uncomplicated positive reports. Conclusions: None of the pharmacological agents tested for stuttering have been shown in methodologically sound reports to improve stuttering frequency to below 5%, to reduce stuttering by at least half, or to improve relevant social, emotional, or cognitive variables. These findings raise questions about the logic supporting the continued use of current pharmacological agents for stuttering.