ABSTRACT

It has been common to say that studies should address not just the question of what works, but also how, where, for whom and at what cost? A unifying framework for such an approach is the theory of change. This paper lays out an approach for using such a theory-based approach to systematic reviews, discussing issues which arise in mixed-methods causal chain analysis. I illustrate the funnel of attrition which is a heuristic device to understand why effect sizes are lower at the higher reaches of the causal chain, including why participation is less than usually expected. Examples are given from the international development sector.

中文翻译：

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基于理论的系统评价

摘要

人们常说，研究不仅要解决什么起作用的问题，而且要解决如何，在哪里，为谁服务以及以什么代价？这种方法的统一框架是变革理论。本文提出了一种使用这种基于理论的方法进行系统评价的方法，并讨论了混合方法因果链分析中出现的问题。我举例说明了损耗的漏斗，它是一种启发式工具，可以理解为什么在因果链的较高范围内效应的大小较低，包括为什么参与比通常预期的要少。国际发展部门举了一些例子。