The first definition of something named โ€œtheory-based evaluationโ€

โ€œA theory-based evaluation of a program is one in which the selection of program features to evaluate is determined by an explicit conceptualization of the program in terms of a theory [โ€ฆ] which attempts to explain how the program produces the desired effects. The theory might be psychological [โ€ฆ] or social psychological [โ€ฆ] or philosophical [โ€ฆ]. The essential characteristic is that the theory points out a causal relationship between a process A and an outcome B.โ€

– Carol Taylor Fitz-Gibbon and Lynn Lyons Morris (1975)

References

Fitz-Gibbon, C. T., & Morris, L. L. (1975). Theory-based evaluation. Evaluation Comment, 5(1), 1โ€“4. Reprinted in Fitz-Gibbon, C. T., & Morris, L. L. (1996). Theory-based evaluation. Evaluation Practice, 17(2), 177โ€“184.

Worthen, B. R. (1996). Editorโ€™s Note: The Origins of Theory-Based Evaluation. Evaluation Practice, 17(2), 169โ€“171. This comment traces the path back to Fitz-Gibbon and Morris (1975).