Is more better than less? An analysis of children's mental health services

To assess the dose-response relationship for outpatient therapy received by children and adolescents-that is, to determine the impact of added outpatient visits on key mental health outcomes (functioning and symptomatology).

The results presented involve analyses of data from the Fort Bragg Demonstration and are based on a sample of 301 individuals using outpatient services.

This article provides estimates of the impact of outpatient therapy based on comparisons of individuals receiving differing treatment doses. Those comparisons involve standard multiple regression analyses as well as instrumental variables estimation. The latter provides a means of adjusting comparisons for unobserved or unmeasured differences among individuals receiving differing doses, differences that would otherwise be confounded with the impact of treatment dose.

Using structured diagnostic interviews and behavior checklists completed by the child and his or her caretaker, detailed data on psychopathology, symptomatology, and psychosocial functioning were collected on individuals included in these analyses. Information on the use of mental health services was taken from insurance claims and a management information system. Services data were used to describe the use of outpatient therapy within the year following entry into the study.

Instrumental variables estimation indicates that added outpatient therapy improves functioning among children and adolescents. The effect is statistically significant and of moderate practical magnitude. These results imply that conventional analyses of the dose-response relationship may understate the impact of additional treatment on functioning. This finding is robust to choice of functional form, length of time over which outcomes are measured, and model specification. Dose does not appear to influence symptomatology.