In 2008, we conducted a literature review of 137 publications, which were chosen from an initial Google Scholar search that yielded more than 10,000 hits. We selected only those publications with an identifiable peer review process and a stated economic assessment method as a requisite for publication. We classified studies according to the unit of assessment studied, including measuring impacts on farmers/households, trade, industry/national, and consumers.

The literature review showed that:

  • Bt cotton is the most-studied crop and trait combination
  • Most studies were conducted in China, India, and South Africa
  • On average, the adoption of Genetically Modified crops was profitable—but averages mask variability by agro-climate, host cultivar, and farmer
  • This collection of studies concluded that too few traits have been studied and there are too few cases/authors implementing such studies. Taking this into consideration, generalization about all GM crops should not be drawn yet.
  • Assessment methods need improvement, especially those dealing with household decision-making processes, risk and uncertainty, different types of selection bias, and endogeneity
  • More time is needed to describe adoption and better methods to describe adoption in an ex ante setting.

Research in the next decade needs to focus on:

  • Information and knowledge flows (to/from farmer )
  • Gender, generational and other cross-cutting issues
  • Impacts on poverty and inequality
  • Externalities and other institutional issues


Smale, Melinda; Zambrano, Patricia; Gruère, Guillaume; Falck-Zepeda, José; Matuschke, Ira; Horna, Daniela; Nagarajan, Latha; Yerramareddy, Indira; Jones, Hannah. 2009. Measuring the economic impacts of transgenic crops in developing agriculture during the first decade: Approaches, findings, and future directions. (Food policy review 10) Washington, D.C.: International Food Policy Research Institute (IFPRI) 107 pages.