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New Guide Book on Ex-Post Evaluation Available!


Long-term evaluations (LTE) typically occur after program implementation is complete, and can provide crucial information on whether outcomes are sustained over time, allowing USAID to make long-term strategic management and funding decisions.

The Expanding the Reach of Impact Evaluations (ERIE) mechanism, under the Global Development Lab’s MERLIN Program, has developed a valuable Guide, to assist projects set up for LTEs. This guide considers three main scenarios for USAID Missions, Bureaus and Independent Offices that might be interested in carrying out a LTE:

  1. Setting up an LTE for a new program. Programs may decide to put in place LTE designs from the onset of a program, if decision-makers anticipate that outcomes will be realized over a long-term time horizon. 
  2. Following up on a previously conducted impact evaluation. LTEs can be implemented as follow-ups to previously conducted impact evaluations of the same program.
  3. Designing LTEs ex-post. Program managers may be interested in generating evidence about program effectiveness from activities that did not previously measure impact, in order to make decisions about continuing, replicating, or scaling the program. While challenging, it is sometimes possible to retroactively identify or reconstruct a comparison group that did not receive the intervention. 

The guide assumes that programs may not have prior experience with impact evaluations. It comfortably walks through common impact evaluation methods, how they are applied in the long-term, and potential sources of data. Additionally, the guide will help USAID teams determine if they are well suited for conducting an LTE, and provides several examples of how LTE have benefited past programs across a variety of sectors. 

For more information, please contact Sophia van der Bijl ([email protected]).

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