The Chronic Care Model (CCM) of Wagner was used to identify the elements of chronic care management. The CCM captures six components which all conceive elements on practice level to structure chronic care such as software applications for decision support or education for self-management support. The CCM elements that were included in this questionnaire were selected and made measurable based on the literature and the expert opinion of about twenty professionals working in the thrombosis field.
The characteristics of the chronic care management identified with the questionnaire were described by five components of the CCM namely: health care organization (i.e. the organizations’ focus on chronic care for instance by incident reporting system); self-management support (i.e. supporting patients to manage their condition for instance by self-management education); delivery system design (i.e. the organization of providing care such as other roles/teams); decision support (i.e. integration of evidence-based clinical guidelines into practice for example by a reminder system) and clinical information system (i.e. systems that support the information exchange).
The identified chronic care management elements applied by the Anticoagulant Clinic regions were hypothesized to improve the chronic care management and as a consequence the patient outcomes as suggested by the CCM. Although the sixth component of the CCM – community resources and policies – was relevant for chronic care management (e.g. legislation to allow self-management), this was not taken into account in this study because the variation in this element differs on another level than the level of analysis of this study, i.e. the Anticoagulant Clinic regions
**Data Analysis:**
First, the associations between the individual chronic care elements and the quality of care were studied as shown in this dataset. These regression analyses were corrected for the type of reagent (Innovin or other reagents) which was significantly associated with quality of care (p = 0.008). The analysis showed that the variables ‘insight in waiting times’ (as proxy for patient orientation) and the ratio ‘specialized nurses versus doctors’ were associated with a significant higher number of patients within the therapeutic range. Furthermore, only the ratio ‘specialized nurses versus doctors’ are statistically significant associated with the number of patients within the target range. No statistically significant associations were observed with the number of patients below the therapeutic range.
Second, the association between the overall use of chronic care management and the patient outcomes was studied. The analysis showed that the use of more CCM components was positively associated with better patient outcomes since the number of components was associated with a higher percentage of patients within the therapeutic range (B = 1.248; p = 0.017) and target range (B = 1.358; p = 0.024). The use of more CCM components was not significantly associated with the percentage of patients below the therapeutic range (B = -0.485; p = 0.073).
