Statistics
All statistical analysis was performed using the Statistical package for the Social Sciences (SPSS) Version 21. e results were presented as numbers and percentages, median and mean values, i e. for Background characteristics. For tests of differences between groups, we used the Chi square test for categorical variables (including the EQ-index variables) and the Mann-Whitney U for the VAS-scale. The Sign test was used to examine differences between baseline (before coronary angiography) and 6-month follow up regarding to the EQ-index variables. No index tariff system was used regarding the EQ-index.
The Wilcoxon test was used for paired comparisons of the VAS scale between baseline and 6-month follow up. A p value of 0.05 or less was considered significant. There were no missing data in patient characteristics except for one patient regarding smoking status Fourteen patients were lost to follow-up at six months. The study protocol conforms to the Declaration of Helsinki and was approved by the Regional Medical Ethics Committee in Uppsala, Sweden.