Effectiveness
Findings
The WWC review of interventions for beginning reading addresses student outcomes in four domains: alphabetics, fluency, comprehension; and general reading achievement. 1 The studies included in this report covers only the comprehension domain. Within comprehension, results for two constructs, vocabulary development and reading comprehension, are reported. The findings below present the authors' estimates and WWC-calculated estimates of the size and the statistical significance of the effects of CIRC® on students. 2
Comprehension. For reading comprehension, Bramlett (1994) reported a statistically significant positive effect of CIRC® on the Reading Comprehension subtest of the California Achievement Test (CAT). According to WWC calculations, the effect was not statistically significant. For vocabulary, the study authors did not find statistically significant effects of CIRC® on the CAT Word Analysis subtest nor on the CAT Reading Vocabulary subtest. The WWC found that the average effect size across the three comprehension outcomes was neither statistically significant nor large enough to be considered substantively important according to WWC criteria (that is, an effect size at least 0.25).
For reading comprehension, Skeans (1991) did not find a statistically significant effect of CIRC® on the Metropolitan Achievement Test (MAT) Reading Comprehension subtest. For vocabulary, the study author reported a statistically significant positive effect on the Vocabulary subtest of the MAT. According to WWC calculations, the effect was not statistically significant. The WWC found that the average effect size across the two outcomes was neither statistically significant not large enough to be substantively important.
Rating of effectiveness
The WWC rates the effects of an intervention in a given outcome domain as: positive, potentially positive, mixed, no discernible effects, potentially negative, or negative. The rating of effectiveness takes into account four factors: the quality of the research design, the statistical significance of the findings,2 the size of the difference between participants in the intervention and the comparison conditions, and the consistency in findings across studies (see the WWC Intervention Rating Scheme).
2 The level of statistical significance was reported by the study authors or, where necessary, calculated by the WWC to correct for clustering within classrooms or schools and for multiple comparisons. For an explanation, see the WWC Tutorial on Mismatch. See the Technical Details of WWC-Conducted Computations for the formulas the WWC used to calculate the statistical significance. In the case of CIRC®, corrections for clustering and multiple comparisons were needed.
