Advance care planning 1 Advance directives Communication 1 General practice 1 Health services for the aged 1 Physician–patient relations 1 advance care planning 1 aged 1 article 1 confounding variable 1 controlled study 1 conversation 1 elderly care 1 female 1 general practice 1 general practitioner 1 human 1 living will 1 major clinical study 1 male 1 physician 1 pretest posttest design 1 primary medical care 1 questionnaire 1 trust 1