Types of Evaluation
There are many different types of evaluations depending on the object being evaluated and the purpose of the evaluation. Perhaps the most important basic distinction in evaluation types is that between formative and summative evaluation. Formative evaluations strengthen or improve the object being evaluated -- they help form it by examining the delivery of the program or technology, the quality of its implementation, and the assessment of the organizational context, personnel, procedures, inputs, and so on. Summative evaluations, in contrast, examine the effects or outcomes of some object -- they summarize it by describing what happens subsequent to delivery of the program or technology; assessing whether the object can be said to have caused the outcome; determining the overall impact of the causal factor beyond only the immediate target outcomes; and, estimating the relative costs associated with the object.
Formative evaluation includes several evaluation types:
needs assessment determines who needs the program, how great the need is, and what might work to meet the need
evaluability assessment determines whether an evaluation is feasible and how stakeholders can help shape its usefulness
structured conceptualization helps stakeholders define the program or technology, the target population, and the possible outcomes
implementation evaluation monitors the fidelity of the program or technology delivery
process evaluation investigates the process of delivering the program or technology, including alternative delivery procedures
Summative evaluation can also be subdivided:
outcome evaluations investigate whether the program or technology caused demonstrable effects on specifically defined target outcomes
impact evaluation is broader and assesses the overall or net effects -- intended or unintended -- of the program or technology as a whole
cost-effectiveness and cost-benefit analysis address questions of efficiency by standardizing outcomes in terms of their dollar costs and values
secondary analysis reexamines existing data to address new questions or use methods not previously employed
meta-analysis integrates the outcome estimates from multiple studies to arrive at an overall or summary judgement on an evaluation question