Minimum n and Confidence Intervals: Proficiency and Exclusion of Special Education Students

The effect of varying confidence interval size and minimum-n size for the special education subgroup on adequate-yearly-progress (AYP) determinations and student exclusion was examined using actual data from five states. Passing rates increased with minimum-n size and confidence interval size, but exclusion rates increased also. The effect of minimum-n size was projected to attenuate somewhat with the change to all-grade testing.