High age, low social class, being single and travelling a long distance to the screening facility seem to constitute factors preventing participation in AAA screening after an initial postal invitation. In the Danish study by Lindholt et al. the proportion attending screening decreased significantly with increasing age (p=0.04). The mean attendance rate for people living within 20 km of the screening facilities was 77.5% while it was 69.8% for people living further away. The mean attendance rate for married men was 78.8% while it was lowest (59.1%) for those who never married. The mean attendance rate for people from the higher social classes was 81.3% while it was 72.6% among the lower social classes (p<0.01) {35}.

An American cohort study reported a compliance rate of 98.5% during follow-up after implementing an AAA surveillance pathway. Patients diagnosed with an AAA >4.0 cm were entered into the clinical pathway incorporating continuity of AAA care from a single provider. A shared database and a facilitator were factors securing the pathway, which included an initial telephone contact, clinical appointment within 2 weeks including discussions and education on AAA (oral and in print) and relatives being encouraged to participate. the pathway also included regular update by phone and letters as well as possibility for patients to phone during the regular follow-up time. Unnecessary clinic visits and travel were avoided and accommodations for transport arranged. Missed appointments were followed up {36}.