Measuring the economic impacts of GM crops in developing
agriculture poses particular challenges. In order to ensure that
information generated is relevant and usable, continued
improvement in methods is needed as diffusion of these crops
steadily expands. In the first decade of published studies, given
the characteristics of early adoption, researchers were not often
able to effectively control for various types of potential bias created
by sampling, measurement, or estimation methods. Several
published studies present exemplary approaches. The
objective of pilot studies assembled here, all based on farmer
surveys, was to attempt to apply recommended approaches
within a constrained budget of $20,000-40,000 in countries and
crops that had received little research attention. Case studies
present findings, illustrate difficulties, and suggest means of
overcoming them. Overall, we call for establishing research consortia
to monitor the impacts of GM crops based on comprehensive
national sampling frames in which ad hoc surveys can be
embedded.