A welfare economic approach to measure outcomes in stuttering: comparing willingness to pay and quality adjusted life years.

PURPOSE: The purpose of this study was to compare two welfare outcome measures, willingness to pay (WTP) and quality adjusted life years (QALYs) gained, to measure outcomes in stuttering. METHOD: Seventy-eight adult participants (74 nonstuttering and 4 persons with stuttering) completed one face-to-face structured interview regarding how much they would be willing to pay to alleviate severe stuttering in three interventions of varying impact. These data were compared with QALYs gained as calculated from time trade off (TTO) and standard gamble (SG) data. RESULTS: Mean (median) WTP bids ranged from US $16,875 (8000), for an intervention resulting in improvement from severe stuttering to mild stuttering, to US $41,844 (10,000) for an intervention resulting in a cure of severe stuttering. These data were consistent with mean changes in QALYs for the same stuttering interventions ranging from 2.19 (using SG) to 18.42 (using TTO). CONCLUSIONS: This study presents the first published WTP and QALY data for stuttering. Results were consistent with previous cost-of-illness data for stuttering. Both WTP and QALY measures were able to quantify the reduction in quality of life that occurs in stuttering, and both can be used to compare the gains that might be achieved by different interventions. It is widely believed that stuttering can cause reduced quality of life for some speakers; the introduction into this field of standardized metrics for measuring quality of life is a necessary step for transparently weighing the costs and consequences of stuttering interventions in economic analyses. EDUCATIONAL OBJECTIVES: The reader will be able to (a) describe the underlying theoretical foundations for willingness to pay and quality adjusted life years, (b) describe the application of willingness to pay and quality adjusted life years for use in economic analyses, (c) compare and contrast the value of willingness to pay and quality adjusted life years in measuring the impact of stuttering treatment on quality of life, (d) interpret quality adjusted life years, and (e) interpret willingness to pay data.

Assessment of respondent acceptability for preference measures in stuttering.

PURPOSE: To assess the feasibility of using one or more of four standard economic preference measures to assess health-related quality of life in stuttering, by assessing respondents' views of the acceptability of those measures. METHOD AND RESULTS: A graphic positioning scale approach was used with 80 adults to assess four variables previously defined as reflecting the construct of respondent acceptability (difficulty of decision making, clarity of text, reasonableness for decision making, and comfort in decision making) for four types of preference measurement approaches (rating scale, standard gamble, time trade-off, and willingness to pay). A multivariate repeated measures analysis of variance (p<.001) and follow-up univariate repeated measures analyses of variance (all p<.01) were all significant, indicating that respondents perceived differences among the preference measurement methods on all four acceptability variables. CONCLUSION: The rating scale was perceived as the easiest, clearest, most reasonable, and most comfortable tool, but it is not a measure of utility (an economic term for desirability or worth). If utility is the objective, such as for cost-utility analyses in stuttering, then the present results suggest the use of standard gamble (rather than time trade-off). These results also support the use of willingness to pay assessments for cost-benefit analyses in stuttering. These findings supplement results previously obtained for other chronic conditions. LEARNING OUTCOMES: The reader will be able to: (1) describe how four standard economic preference measures [rating scale (RS), time trade-off (TTO), standard gamble (SG), and willingness to pay (WTP)] can be used in economic analyses; (2) describe how RS, TTO, SG and WTP can be measured; and (3) describe how respondents perceive the use of RS, TTO, SG and WTP in measuring changes in stuttering.

Stuttering treatment research 1970-2005: I. Systematic review incorporating trial quality assessment of behavioral, cognitive, and related approaches.

PURPOSE: To complete a systematic review, with trial quality assessment, of published research about behavioral, cognitive, and related treatments for developmental stuttering. Goals included the identification of treatment recommendations and research needs based on the available high-quality evidence about stuttering treatment for preschoolers, school-age children, adolescents, and adults. METHOD: Multiple readers reviewed 162 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: Analyses found 39 articles that met at least 4 of the 5 methodological criteria and were considered to have met a trial quality inclusion criterion for the purposes of this review. Analysis of those articles identified a range of stuttering treatments that met speech-related and/or social, emotional, or cognitive outcomes criteria. CONCLUSIONS: Review of studies that met the trial quality inclusion criterion established for this review suggested that response-contingent principles are the predominant feature of the most powerful treatment procedures for young children who stutter. The most powerful treatments for adults, with respect to both speech outcomes and social, emotional, or cognitive outcomes, appear to combine variants of prolonged speech, self-management, response contingencies, and other infrastructural variables. Other specific clinical recommendations for each age group are provided, as are suggestions for future research.

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.

The Stuttering Treatment Research Evaluation and Assessment Tool (STREAT): evaluating treatment research as part of evidence-based practice.

PURPOSE: This article presents, and explains the issues behind, the Stuttering Treatment Research Evaluation and Assessment Tool (STREAT), an instrument created to assist clinicians, researchers, students, and other readers in the process of critically appraising reports of stuttering treatment research. METHOD: The STREAT was developed by combining and reorganizing previously published recommendations about the design and conduct of stuttering treatment research. CONCLUSIONS: If evidence-based practice is to be widely adopted as the basis for stuttering assessment and treatment, procedures must be developed and distributed that will allow students, clinicians, and other readers without specialized knowledge of research design to critically appraise treatment research reports. The STREAT is intended to be such an instrument: It represents the consensus of previous methodological recommendations; it is consistent with and complements existing recommendations in evidence-based medicine and in the broader science of treatment outcome evaluation; and it is formatted into a single instrument for ease of use.

Using preference-based measures to assess quality of life in stuttering.

PURPOSE: The purpose of this study was to determine whether standard pharmaco-economic preference methods can be used to assess perceived quality of life in stuttering. METHOD: Seventy-five nonstuttering adults completed a standardized face-to-face interview that included a rating scale, standard gamble, and time trade-off preference measures for 4 health states (your health and mild, moderate, and severe stuttering) in the context of 2 anchor states (perfect health and death). RESULTS: Results showed mean utility values between .443 for severe stuttering estimated using the rating scale technique and .982 for respondents' own current health estimated using a standard gamble technique. A two-way repeated measures analysis of variance and post hoc tests showed significant effects for method, health state, and the interaction. CONCLUSIONS: These results confirm that utility estimates can differentiate between stuttering severity levels and that utility scores for stuttering conform to the known properties of data obtained using these standard measurement techniques. These techniques, therefore, can and should be further investigated as potential contributors to complete measurement protocols for the study and treatment of stuttering.

Science and pseudoscience in communication disorders: criteria and applications.

PURPOSE: The purpose of this tutorial is to describe 10 criteria that may help clinicians distinguish between scientific and pseudoscientific treatment claims. The criteria are illustrated, first for considering whether to use a newly developed treatment and second for attempting to understand arguments about controversial treatments. METHOD: Pseudoscience refers to claims that appear to be based on the scientific method but are not. Ten criteria for distinguishing between scientific and pseudoscientific treatment claims are described. These criteria are illustrated by using them to assess a current treatment for stuttering, the SpeechEasy device. The authors read the available literature about the device and developed a consensus set of decisions about the 10 criteria. To minimize any bias, a second set of independent judges evaluated a sample of the same literature. The criteria are also illustrated by using them to assess controversies surrounding 2 treatment approaches: Fast ForWord and facilitated communication. CONCLUSIONS: Clinicians are increasingly being held responsible for the evidence base that supports their practice. The power of these 10 criteria lies in their ability to help clinicians focus their attention on the credibility of that base and to guide their decisions for recommending or using a treatment.