Organizational borders and local public health delivery systems: Using an empirical typology to assess system change and performance

RATIONALE: The availability of essential public health services varies widely across states and communities, as do the mechanisms for organizing and delivering these services. To elucidate these issues, we developed an empirical method of classifying local delivery systems based on the scope of public health activities performed within the community (scope), the proportion of activities contributed by the governmental public health agency (concentration), and the range of other organizations contributing to these activities (integration). In this analysis, we use the empirical typology to assess structural change in public health systems over time. METHODS: A stratified random sample of the nation's 3000 local health department directors (n=497) were surveyed in 1998 (78% response) and again in 2006 (70% response) to determine the availability of 20 common public health activities within their jurisdictions and to identify the types of organizations participating in each activity. Principal components analysis methods were used to classify systems into one of seven structural categories based on the scope, concentration, and integration of activities. Multivariate hierarchical regression models were used to estimate associations between structural change, system performance and population health. RESULTS: Moderate increases in system scope and substantial increases in integration were observed during the 8-year period (p<0.05), while concentration remained relatively stable. Systems experiencing increases in scope and integration were more likely than their counterparts to achieve improvements in perceived performance and reductions in mortality from several preventable causes of death. CONCLUSIONS: Organizational integration, or "border-crossing" within public health systems, contributes to expanded system capacity and may lead to improved population health.