Similarly, Levin and O’Donnell (1999, p. 215) distinguished
between the purposes of observational/correlational studies, on the
one hand, and randomized intervention studies, on the other,
indicating why the latter are needed in education:
[W]e do not mean to imply that randomized [intervention] studies are
appropriate for all areas of educational research inquiry, for they most
certainly are not. . . . Systematic observation, rich description, and
relationship documentation—with no [researcher-controlled randomization]
component—may well suffice for characterizing many classroom
processes and behaviors of both practical and theoretical consequence.
For the prescription of instructional interventions (e.g.,
alternative teaching methods, learning strategies, curricular materials)
and other school- or other system-based “innovations,” however,
randomized [intervention] studies could go a long way toward responding
to [recent calls for improving the quality of educational
research to inform] “our understanding of a number of enduring
problems of practice” (McGuire, 1999).