Types of Evaluation

There are many types of evaluations; however, most can be divided into two major categories: formative and summative. 

Formative Evaluation

The purpose of a formative evaluation is to strengthen or improve how a program is implemented. It is usually conducted during the beginning stages of a program. It assesses the implementation of the program, including the inputs into a program, such as procedures and resources (human and financial). Formative evaluation is usually used to see if any changes or modifications to a program and/or its implementation are needed. The types of formative evaluations include needs assessment, evaluability assessment, and process evaluation.
For example, a treatment service organization has decided to develop and implement a new addiction treatment program that incorporates greater family involvement. The organization develops a program logic model which identifies aspects of the program, such as:

• Financial, material, and human resources or inputs (e.g., funding from a government body or foundation, existing office space, one FTE staff)
• Activities (provide joint counselling services to people who have addictions and to their family members)
• Outputs (hold a minimum of five counselling sessions per individual, provide the individual and family members with a workbook)
• Outcomes (80% of individuals and their family members complete five counselling sessions)
• Ultimate goals (improved health for the individual with an addiction; family is better able to support the individual)

A formative evaluation of this new program might examine whether the program is being carried out as it was intended, if the resources and inputs are sufficient to meet the program’s goals, if the program activities match those in the logic model, and if the program is in a good position to achieve its outputs, outcomes, and ultimate goals. Based on this information, the program can be refined or improved. Formative evaluation is used to improve the implementation of a program.

Summative Evaluation

The purpose of a summative evaluation is to see if the program is doing what it was intended to do. It is used to assess the outcomes or the results of a program and is concerned with the program’s effectiveness. These evaluations typically describe what happened following the delivery of the program, assess whether the program caused the outcome, compare different versions of a program, determine the overall impact of the program, and estimate the relative costs of the program. Often, decisions about whether or not to continue a program are made through this type of evaluation.
Types of summative evaluation include outcome evaluations, impact evaluations, and cost-effectiveness and cost-benefit analysis.

For example, the treatment service organization and its funders want to know if its new addiction treatment program incorporating greater family involvement has been successful. A summative evaluation would compile information from many different sources (e.g., program documents, surveys or questionnaires, interviews, focus groups) to determine if clients showed improved outcomes compared to the original program. Based on this information, decisions about whether or not to continue the program can be made.