Table 1

Data collection

Sources of data	Data
Mid-level provider (three NPs, two PAs and two practice nurses)	Observation (4×4 hours) Questionnaire Interview (after observation)
Manager involved in physician substitution	Questionnaire Interview
Supervisor/manager of the mid-level provider	Interview
ECPs with whom the mid-level provider collaborates most intensely	Observation (2×2 hours) Questionnaire Interview (after observation)
ECPs with whom the mid-level provider collaborates directly	Questionnaire Interview
Head of the ECPs	Interview
Five nurses/healthcare assistants/nursing team leaders with whom the mid-level provider collaborates	Interview
Five patients the mid-level provider takes care of and/or their informal caregiver	Interview
Patient council, family council or patient–family council	Focus group interview
Documents	Mission and vision of the organisation Mission and vision of the organisation on physician substitution Job description of all mid-level providers in the organisation and of the ECP Working arrangements for the mid-level provider and the ECP Treatment protocols for the mid-level provider Annual report of the organisation of the preceding year Information about the mid-level provider for patients and family

ECPs, elderly care physicians; NPs, nurse practitioners; PAs, physician assistants.