Contribution Analysis and Estimating the Size of Effects: Can We Reconcile the Possible with the Impossible?

While contribution analysis provides a step-by-step approach to verify whether and why an intervention is a contributory factor to development impact, most contribution analysis studies do not quantify the ‘share of contribution’ that can be attributed to a particular support intervention. The authors explore how contribution analysis can be stretched so that it can give some sense of the importance of a contribution in a quantitative manner.