Explanation for choice of comparators
comorbidity
To evaluate whether the integration of APNs in the primary care setting improves the care of multimorbid patients, a control group from German health care insurance was selected. Persons in the control group are considered to be receiving the current standard care. Therefore, a comparison between the new intervention and standard care is possible. To minimize the risk of confounding variables, participants in the intervention and control groups will be matched for the following variables: (1) age, (2) gender, (3) comorbidity and (4) living in a nursing home.