Dorien Brouwer

79 Changes in determinants of health-related behavior over time PART 1 Statistical analysis Statistical analysis was performed with STATA 12.1 statistical package (Statacorp, College Station, Texas). Fear, self-efficacy and response efficacy at baseline, after six weeks and three months were described and differences were tested with Wilcoxon signed rank tests. We studied the relation between determinants of intention to change health-related behavior at baseline and after three months with univariable an multivariable linear regression. Adjustments were made for age, sex, baseline scores and other determinants. For instance in analyzing self-efficacy adjustments were made for age, sex, baseline self-efficacy scores and response-efficacy and fear. Results As described earlier we included 100 patients in the DECIDE study between February and October 2012. Follow up was completed in 87 patients: 5 patients refused follow-up, 1 patient was lost to follow-up, 1 patient was excluded because of severe other comorbidity, 1 because of intracerebral hematoma during follow-up, 2 patients because of misdiagnosis, and 3 patients were discharged to another hospital. No significant differences in baseline characteristics were found between included patients and excluded patients (data not shown). Mean age was 64 years (SD 12), 60% of the patients were male and 53% had a TIA (Table 1). Median self-efficacy score at baseline was 4.3 (IQR 3.9-4.7), median fear 16 (IQR 7-21), and response efficacy 10 (9-12). Fear was significantly higher at baseline than at 3 months (mean difference 2.0; 95% CI 0.78-3.9). This significance remained after adjustment for age, sex, baseline self-efficacy and response efficacy (0.37; 95% CI 0.11-0.64, Table 3). Fear started to decrease after six weeks (median fear at 6 weeks 16, at three months 11; p 0.02). No change in self-efficacy or response efficacy was found. [17]