Organizational capacity and implementation change: a comparative case study of heart health promotion in Ontario public health agencies

This paper reports the results of a comparative case study that examines factors influencing changes in implementation of heart health promotion activities in Ontario public health units. The study compared two cases that experienced large changes in implementation from 1994 to 1996, but in opposite directions. Multiple data sources were used, with an emphasis on secondary analyses of quantitative surveys of health units and other community agencies, and in-depth interviews of public health staff, collected as part of the Canadian Heart Health Initiative Ontario Project. Guided by social ecological and organizational theories, changes in implementation were explained by examining changes in (1) organizational predisposition to undertake heart health promotion activities, (2) organizational practices to undertake these activities, (3) other internal organizational factors and (4) external system factors. Findings show that in communities with diverse characteristics, implementation change was most strongly influenced by an interplay of changes in internal features of public health agencies; notably, leadership, structure and staff skills. Findings support a social ecological approach to health promotion by demonstrating the importance of the institutional context in the implementation change process, the interaction of individual (skills) and organizational (structure) levels in explaining implementation change, and community context in shaping the change process. Findings also reinforce the value of strengthening capacity within public health agencies and suggest further research on the implementation change process, especially in different systems and over longer periods of time.