Talking about smoking in primary care medical practice--results of experimental studies from the US, UK and Germany.

Objective: To analyse effects of patient and physician characteristics on questions and advice about smoking in primary care practice and to examine country differences.

Methods: We conducted a factorial experiment, employing filmed scenarios in which actors played the role of patients with symptoms of coronary heart disease (CHD) or type 2 diabetes. Versions were filmed with patient-actors of different gender, age, race, and socioeconomic status.