Table 1.

Major barriers identified from the literature for GPs' systematic engagement in a tobacco and alcohol intervention program, and the efforts to overcome those barriers in the present study

Identified Barriers	Present efforts to overcome the barriers
Fear of infringing the patient's right to self-determination [32]	Information regarding smoking and harmful drinking as objective risk factors for surgery and of the risk-reduction programmes (according to the patient folder) respecting the patient's right to self-determination on informed basis.
Missed the opportunity for promotion of medical benefit and protections from harm (i.e. GPs only engage with patients with smoking-related problems) [23,32,33]	Focus on the evidence of risk-reduction in relation to the current surgical illness
GP limited consultation to addressing patient's agendas relating to surgery [23,24,33,34]	Focus on the evidence of the high-risks of surgery for smokers and harmful drinkers. Systematic approach to identify and intervene
Harming the relationship with the patient [32]	Dissemination of knowledge that the majority of patients expect the GP and the hospital to deal with lifestyle. Use of the surgical illness as a window of opportunity to offer intervention
Not part of the job [23,31]	Only including engaged GPs, who volunteer to participate after informed consent. Focus on the GPs as key persons to initiate the risk reduction programmes in due time prior to surgery.
Too time-consuming [23,28]	The extra workload for the GP was less than 5 minutes per referred high-risk patient for surgery. The resulting increase of the reimbursement was 1/3 for the specific consultation
Lacking confidence and knowledge [25,27-29,34-36]	Simplified the information material, referring process, and guidelines which were to be handled by the GPs
Time not spent effectively due to few quitters [23,34,37]	Distribute knowledge about the high effectiveness of preoperative smoking and alcohol intervention (60-90% quitters)
Shortage of smoking cessation experts to whom the patient could be referred to [23,25,28,30]	Easy access by telephone-answering-machine to smoking cessation expertise, who took over the contact with the smokers and harmful drinkers once referred
Anticipating patient's lack of motivation and interest [26,28,29]	Distribute knowledge that the majority of patients expect the GP and the hospital to deal with lifestyle. Use of the surgical illness as a window of opportunity to offer intervention