BMC Public Health 2007, 7:74 http://www.biomedcentral.com/1471-2458/7/74 When the client recognizes such discrepancies, a certain level of discontent arises that makes change more likely to occur. Discrepancies are developed by exploring the cli- ent's important life values and reviewing how their cur- rent behaviours affect their ideal lifestyle. The third principle, rolling with resistance, is based on the idea that directly challenging resistance is counterproduc- tive to lifestyle change, because it typically results in the client defending the current state of affairs. Rather, resist- ance should be rolled with and channelled instead of con- fronted. Rolling with resistance invites the client to consider a new perspective versus having it imposed. Finally, self-efficacy, or one's confidence in the ability to change a specific behaviour under difficult circumstances, should be supported whenever possible because it is one of the best predictors of treatment outcome. Self-efficacy can be strengthened by affirming past success (i.e., rein- forcement), presenting success stories of others (i.e., mod- elling), and expressing belief in the client's potential to change. Together, these four principles guide the first phase of CBT. The patient will become motivated and at that point, the Problem Solving Treatment can be started. Problem Solving Treatment (PST) PST is a practical skill building treatment and might there- fore be effective in achieving lifestyle changes in patients with diabetes [28]. PST was originally described by D'Zurilla and Godfried [29] and later expanded and refined by D'Zurilla and Nezu [30]. PST may be defined as the self-directed cogni- tive-behavioural process by which a person attempts to identify effective or adaptive solutions for specific prob- lems encountered in everyday living [31]. The effects of PST have been shown to be effective in patients with depression [32-34]. However, PST is potentially useful in the treatment of any disorder in which a patient is experi- encing multiple daily problems and stresses and is not coping effectively with them [31]. Therefore, patients with diabetes might benefit from PST as they have to cope with many complex tasks. They have to take care of their diet, lifestyle, physical activity and administration of oral med- ication or insulin in order to achieve an optimal glycaemic control and to reduce their cardiovascular risk factors. Also, psychological problems are common in these patients. PST might increase the patients' ability to solve their problems in a structured way and their confidence in facing future problems and therefore improve their diabe- tes self-management. PST can be considered as a series of stages [28]: 1. Explanation of the intervention and its rationale 2. Definition and breaking down of the problem 3. Establishing achievable goals for problem resolution. Achievable goals are SMART goals: Specific, Measurable, Achievable, Relevant, Timed 4. Generating multiple possible solutions 5. Evaluating and choosing the solution 6. Implementing the preferred solution 7. Evaluating the outcome Another reason why PST may be suitable in patients with diabetes is that practice nurses can deliver it because it is relatively brief, as it lasts between three and six sessions of 30 minutes [32,35]. Objectives The primary objective of our study is to investigate if cog- nitive behavioural therapy, when added to managed dia- betes care, is effective in achieving changes in cardiovascular risk profile. The secondary objective is to assess whether the cognitive behavioural therapy is effec- tive in changing lifestyle. Methods Design of the study The study is a randomised controlled trial (RCT). The Medical Ethical Committee of the VU University Medical Center in Amsterdam approved the study design, proto- cols, information letters to the patients and informed con- sent form. Setting The trial is conducted within 'the Diabetes Care System (DCS)', a managed care system that was implemented in The Netherlands, as described above. This care system has a well organised infrastructure with experienced medical assistants, diabetes nurses and dieticians and is therefore a suitable setting to implement a new therapy for patients with diabetes. Study population The source population consist of patients with type 2 dia- betes of participating GPs. Selection criteria for the GPs are that they have a practice nurse and that they are part of the DCS. GPs will be informed about the study by one of the researchers (GN) and a diabetes nurse and are asked to participate. They have to sign an intention declaration to confirm participation. Page 3 of 10 (page number not for citation purposes)