Though these results sound promising, there were several measurement
problems with the studies. The research by itself does not prove that the
implementation of the CDG program was responsible for the positive outcomes
noted. Given the correlational nature of the study, it could just as well be, for
example, that the schools that are fully implementing the CDG model were also
implementing other educational programs that directly impact academic
achievement. More complete guidance implementation and higher student grades
might both result from the schools' organizational structure, leadership and/or
personnel strengths rather than being causally related to each other.
Another problem with the studies is related to the self-report nature of the
data that was collected, which makes it impossible to measure the effect size of the
implementation of the CDG program. No additional institutional data was used to
cross-validate the information students, teachers, or counselors were reporting.
Future studies of this sort would ideally have inclusion of standardized
achievement measures in addition to other institutional data, a report of
intervention effect size, and/or some check of integrity related to the
implementation of the program components.