Aims, design and methods of the Smoking and Nicotine Dependence Awareness and Screening (SNICAS) study.

The objectives of the Smoking and Nicotine Dependence Awareness (SNICAS) study are to provide nationally representative data on the prevalence of smoking and smoking dependence of primary care patients and the frequency in which smoking cessation interventions are offered and provided in primary care. With the inclusion of both providers' (doctor) and patients' perspectives, the study also attempts to identify the needs and motivational status for smoking cessation as reported by the patients and as perceived by the doctor. The Smoking and Nicotine Dependence Awareness study uses a two-stage epidemiological design. Stage 1 consists of a pre-study characterization of a nationwide sample of 889 primary care doctors (conservative response rate: 50%). Stage 2 consists of a cross-sectional assessment of unselected consecutive patients (n = 28,707, conservative response rate: 52.8%) on the study's target day, by means of patient questionnaire and a structured clinical appraisal of each patient by the doctor. This paper provides an overview of the design and methods of the study, informs about sampling and response rates, and examines whether the study sample could be considered representative of German primary care doctors.