Pattern of participation in a cohort aged 50–60 years at first invitation to the service-screening programme with mammography in Stockholm county, Sweden

Background. Mammography screening can only be effective if a high proportion of the invited women attend. The aim of the present study was to search for patterns of participation in women who were invited to five consecutive rounds in a large screening programme. Method. Stockholm service-screening programme started 1989 and invites women between 50 and 69 years of age to mammography with 2 years interval. 64,852 women were eligible for an invitation to all five rounds during a 10-year period and were included in the study. Results. More than 50% attended at all five rounds, and more than 70% at least four rounds. Only 8.5% were permanent non-participants. Women who attended at the first invitation round were more likely to attend also at subsequent rounds. Conclusions. It is possible to reach a high participation also in a large urban screening programme, but it seems that the invitation and examination at first round are most important in order to get a high compliance. Women who come at first round are more likely to come back for routine screening at a majority of subsequent rounds.