Nested Designs in School-Based Mental Health Service Research

This poster presentation describes the challenges of employing a nested design in school-based mental health services research. Nested designs occur when the student is used as the statistical unit of analysis, which in certain cases may violate the “independence of error” assumption. This statistical effect of nesting is due to students being located in classrooms, those classrooms being located in schools, and those schools being located in districts. However, alternative research designs using fewer students and more schools can be costly and administratively complex. This study examines data from 314 students with emotional disturbance and their caregivers from 24 schools in the United States to identify the extent to which nesting or design effects occur in this population. Students were educated in special education settings in elementary, middle, or high schools in nine states. The results show that variables focusing on psychopathology are less affected by nesting but school-related variables such as academic functioning are more affected. Design effects varied by grade level, suggesting that grade should be considered when designing evaluations. The implications of this study for mental health services in schools will be highlighted.