Objectives: Firstly, to determine whether the acceptance rate of the second invitation for breast screening (sent to women who have failed to attend after the first invitation) might be increased by an accompanying letter from a general practitioner (GP letter). Secondly, to identify the additional costs of sending such a letter.
Methods: 465 women registered with four practices in a single health centre were recruited into a randomised controlled trial in which the intervention was the inclusion of a standard, photocopied letter signed by the non-attender's doctor with the second invitation to attend for breast screening. The control group received only the standard invitation from the breast screening centre. The costs associated with the intervention were assessed from data supplied by the breast screening centre, supplemented by direct observation of the preparation of second invitations and semistructured interviews with the staff taking part.
Results: The attendance rate of the test group one month after the second invitation for screening was significantly higher than that of the control group (21% v 10%, P < 0.01). The average cost of a GP letter included with the invitation was 1.1 pence and the marginal cost for each extra attender was 9.6 pence. No non-monetary costs were identified.
Conclusions: The inclusion of a GP letter appeared to be effective and feasible in increasing the attendance rate to the second invitation. This intervention should be tested in other screening groups to confirm the effectiveness of a GP letter and its cost effectiveness.