Major review fails to find positive impacts from certification schemes, calls for more studies

Effects of certification schemes for agricultural production on socio-economic outcomes in low- and middle-income countries by Oya et al. 2017,


We find that the available quantitative evidence does not give a clear picture of the impact – or lack thereof – of certification schemes:
  • Yields: We found no clear effect on yields. While certification is associated with a decrease in yields of 20%, the overall effect is not statistically significant (central estimate -20%, range from -52% to 19%)
  • Price: Prices for certified producers were 14% higher than for non-certified producers (range from 4% to 24%)
  • Income from certified production: Incomes from the sale of produce were 11% higher if the produce was certified (range from 2% to 20%)
  • Wages: We find that wages for workers engaged in certified production were 13% lower than for workers working uncertified employers (central estimate -13%, range from -22% to -3%)
  • Total household income: Effects on the total household income of farmers are unclear. While household incomes of farmers engaged in certified production were 6% higher than those of households not engaged in certified production, the overall effect is not statistically significant (range from -3% to 16%)
  • Assets/wealth: We found no statistically significant effect on wealth. Certified producers on average had slightly higher wealth levels than uncertified producer who had been selected to be similar to them, and the overall effect was a 3% increase in assets, but this effect was not statistically distinguishable from zero (range from -7% to 13%)
  • Illness: We also found no clear effect on producer’s health. Pooling the included studies suggests a 7% lower incidence of illness in certified producers compared to non-certified producers, but the overall effect is not statistically significant (central estimate -7%, range from -16% to 2%)
  • Schooling: Children in households of certified producers receive 6% more schooling than children in households of non-certified producers (range from 0% to 12%)

In most cases, disaggregation by type of CS did not yield conclusive results, although for some CS results were more mixed than for others. Such is the case of Fairtrade for yields and income measures.

The mixed and inconclusive quantitative effects, combined with the wide range of contextual factors to take into consideration, underline that CS operate in complex environments with multiple interventions, goals, actors and contexts, and as such they do not operate in a social, institutional and economic vacuum.