It is best to also perform process-based evaluation in conjunction with outcomes-based evaluation . Process-based evaluation investigate how and why OD programmes produce the results they do rather than analyzing results. Process-based evaluation can be useful if you have had problems during the programme or concerns about the OD programme as a whole.
Questions to ask when using process based evaluation involve asking how employees and practitioners conducted interventions, how they delivered the interventions, how they interacted, what was required of the participants and what would they recommend to improve the programme going forward. It also involves analyzing the strengths, weaknesses, and challenges of a programme.
It is best to do both outcome-based and process-based evaluation at the same time because it will allow you understand the reasons why you received the outcomes you did.