In the third sampling stage (initial screening), all 205 articles and chapters were scrutinized to
determine if they met inclusion criteria. To be considered for inclusion, the articles and chapters had
to (a) explicitly claim that a theory-driven, theory-based, or theory-guided form of evaluation was
used and (b) describe a sufficiently detailed case example, including theory formulation, methods,
and results. Articles and chapters not meeting these criteria were excluded from the sample. Two
reviewers independently screened the 205 articles or chapters to determine whether they met inclusion
criteria. Excluded articles and chapters were adjudicated to verify their exclusion, resulting in a
total of 90 potential book chapters and articles.
In the fourth stage (final screening), two reviewers worked independently to systematically
identify articles or chapters with sufficient or insufficient information for reliable coding. Consensus
between both reviewers verified their inclusion or exclusion. The final sample obtained from this
procedure yielded 45 articles and chapters describing sufficiently detailed case examples of
theory-driven evaluations with satisfactory information for coding.4 In the 20 years since the appearance
of Chen’s book Theory-Driven Evaluations (1990), an average of 10 (SD ¼ 5.43) articles and
book chapters directly related to theory-driven evaluation were published per year. Of these, an average
of two (SD ¼ 1.71) per year were considered adequately detailed and codable case examples for
use in this review.