Randomisation and masking
Randomisation was conducted at PCC level. A total of 28 PCC were included and divided into two strata, rural (n=14) and urban (n=14). The centres in each stratum were then divided into seven blocks of two centres each. One centre in each block was randomised to the intervention group (n=14) and one to the control group (n=14) by the Primary Health Care R&D Region Västra Götaland, Sweden (