Some business organizations have used immunization performance criteria to set penalties and incentives in purchasing negotiations. A study conducted by the Pacific Business Group on Health in 1996, for example, monitored the performance of 13 of California’s largest health maintenance organizations (HMOs) that had agreed to penalties (placing a specified percentage of their premiums at risk) in return for not meeting quality-of-care goals (Schauffler et al., 1999). The authors reported that 8 of the 13 plans missed their targets for childhood immunizations, falling short by 3–12 percent. Five of the plans exceeded their targets (by an average of 9.3 percent) within a range of 2–19 percent. Some HMOs excuse low performance with claims that plan participants receive immunization services outside the network of HMO providers, in settings such as county health departments or community clinics, and data on this utilization may not be reported back routinely to the plans or recorded in patients’ medical records (Schauffler et al., 1999). Many monitoring groups, however, including the Pacific Business Group on Health, hold participating plans responsible for tracking use of services, both within and outside the plan.
While some of the differences between the CASA and HEDIS criteria for inclusion are technical, the fundamental question is not. At the heart of the difference is the issue of when a provider or health plan takes responsibility for a child and when that provider or plan should be held accountable for the child’s health care, including immunization coverage. The HEDIS criteria often exclude a large segment of the population— possibly too large a segment. It does not make sense to hold a plan accountable for the services delivered to a child who has just joined, but since most children have had encounters with the health care system before joining a given plan, the criteria may be too generous. It may make more sense to hold a plan accountable for seeing that a child’s previous immunizations are included in his or her record and catching up with the remaining immunizations. On the other hand, the CASA criteria may be too inclusive. Providers have complained that they are being held accountable for children they do not see as “theirs,” that parents may come to a given provider only once for any number of reasons. Some health departments address these issues by reporting on all children selected using the CASA criteria, and then providing additional reports for children who have been followed longer.5 More attention is necessary to the issue of when providers should be held accountable for children who have visited them and how that accountability should be reflected in sample selection for coverage assessments.