Treatment fidelity, or the application of an intervention as it is designed, is a critical issue for the successful implementation of evidence-based practices. Typically it is assumed that evidence-based practices implemented with high fidelity will result in improved outcomes, whereas low fidelity will lead to poorer outcomes. These assumptions presume agreement across researchers and practitioners on what fidelity is, how to measure it, and what level of fidelity optimizes outcomes; however, there is no widespread agreement on any of these issues. This article discusses the dimensions and nuances of treatment fidelity as well as the implications for measuring and analyzing it in relation to student outcomes. The authors review research demonstrating the differential relationship of fidelity across schools, program type, and impact on student outcomes that special educators should consider when designing intervention studies and implementing evidence-based practices. Special educators should prioritize practices and programs with clearly identified components that are empirically validated yet designed flexibly to match various contexts and student populations. Suggestions to support schools in implementing and sustaining evidence-based practices are provided.

治疗保真度或干预的应用设计是成功实施循证实践的关键问题。通常假设以高保真度实施的循证实践将导致改善的结果，而低保真度将导致更差的结果。这些假设假定研究人员和从业人员就什么是保真度、如何衡量保真度以及何种保真度水平可以优化结果达成一致；然而，对这些问题中的任何一个都没有达成广泛的共识。本文讨论了治疗保真度的维度和细微差别，以及衡量和分析与学生成绩相关的影响。作者回顾了表明不同学校、项目类型、以及特殊教育工作者在设计干预研究和实施循证实践时应考虑的对学生成果的影响。特殊教育工作者应优先考虑具有明确确定的组成部分的实践和计划，这些组成部分经过经验验证但灵活设计以匹配各种背景和学生群体。提供了支持学校实施和维持循证实践的建议。