A FRAMEWORK FOR IMPACT ASSESSMENT
Impact assessment is directed at establishing, with as much certanty as possible, whether or not an intervention is producing its intended effects. In orer to do so, it is necessary to measure as rigorously as possinle the outcome of social intercentions and to purify these results by removing the influences of forces other than the intervention being evaluated. The outcomes of social programs are assessed by comp aring information about participants and non participants, be fore and after an intervention, or other less powerful research designs. But the essential considerations involve the systematic rejection of alternative, competing explanations for the obeserved outcomes other than the intervention. The measurement of outcome must be carried out by means of valid and reliable indicators.