These are the BIG questions in program/project evaluations. Has the program caused the observed outcomes/changes? Are the outcomes changing as a result of the implementation of the program? Are the observed outcomes/changes attributable to the program? OR Is the program contributing to the outcomes/changes? Are the outcomes of interest changing? Is there evidence that the program helped achieve (was part of what caused) the outcomes?
Because the real world is so complex, attribution of changes to a specific program is usually a daunting task. As changes in outcome indicators often result from the combined effects of many interventions, it is rare to find ‘clean’ attribution evaluations. Given their high cost, evaluations that focus on attribution are also not feasible.
So what? Evaluation of contribution of programs can serve most of the purposes of program evaluation. Many actors are interested to know the ‘overall changes’ related to their efforts and then the contribution of their programs towards that end. Evaluation of contribution is therefore more feasible and usable than evaluations that try to attribute outcomes to specific programs.
Attribution of outcomes to specific programs needs rigorous evaluation designs, such as Randomized Controlled Trials. The implementation of these designs is usually ideal and thus detached from reality. On the other hand, evaluations that focus on contribution, can employ longitudinal, cross-sectional or case study evaluation designs which are relatively more feasible.