While the terms evaluation and assessment are commonly used interchangeably, I prefer text book definitions which differentiate between the two. According to (Fitzpatrick, Sanders, & Worthen 2011) evaluations are conducted to determine the worth or merit of whatever is evaluated. The consequences stemming from such decisions compels evaluators to use precise tools when developing evaluation plans.
Often, multiple instruments are required to effectively evaluate complex programs. Logic models can provide graphic insights into appropriate tool selection and insertion points. For example, Proponents of the Phillips five-level evaluation model, can employ logic models to determine when to utilize an instrument and whether or not it is summative or formative in nature. The graphic nature of the model can also be used to great effect during stakeholder presentations.
The logic model presented below illustrates this principle, as experienced Training and Development Professionals will make short work of locating appropriate insertion points for assessment instruments. Clearly, level-five ROI calculations cannot take place before x-n personnel have completed the required learning interventions. I will not expound on additional insertion points, as they are equally obvious to the practiced eye.
Fitzpatrick, J., Sanders, J., & Worthen, B. (2010). Program evaluation: Alternative approaches and practical guidelines (4th ed.). Boston, MA: Pearson.