TY - JOUR

T1 - Impact of invitation schemes on screening coverage

T2 - A cohort study from Copenhagen, Denmark

AU - Jacobsen, Katja Kemp

AU - von Euler Chelpin, My

AU - Vejborg, Ilse

AU - Lynge, Elsebeth

PY - 2017/3/1

Y1 - 2017/3/1

N2 - BACKGROUND:The porpuse of mammography screening is to decrease breast cancer mortality. To achieve this a high coverage by examination is needed. Within an organized screening programme, we examined the impact of changes in the invitation schedule on the interplay between coverage and participation.METHOD:We studied nine cohorts aged 50-51 when first targeted by mammography screening in Copenhagen, Denmark. Population data were retrieved from the Danish Civil Registration System; invitation and attendance data from the screening programme database. Data were linked using unique personal identification numbers. Coverage by invitation was defined as (number of invited women/number of targeted women), coverage by examination as (number of screened women/number of targeted women), and participation rate as (number of screened women/number of invited women).RESULTS:Coverage by invitation was close to or above 95% for all newly recruited cohorts. In subsequent invitation rounds, both technical errors and changes in the invitation scheme affected the coverage by invitation. Coverage by examination at first invitation was 72.5% for the first cohort, but dropped to 64.2% for the latest cohort. Furthermore, coverage by examination dropped by increasing invitation number and with omission of re-invitation of previous non-attenders. Participation rate closely reflected changes in the invitation scheme.CONCLUSION:Changes in the invitation schemes influenced coverage by invitation, coverage by examination, and participation rate. We observed a considerable gap between coverage by examination and participation rate, strongly indicating that the latter cannot without reservations, be taken as an indicator of the first.

AB - BACKGROUND:The porpuse of mammography screening is to decrease breast cancer mortality. To achieve this a high coverage by examination is needed. Within an organized screening programme, we examined the impact of changes in the invitation schedule on the interplay between coverage and participation.METHOD:We studied nine cohorts aged 50-51 when first targeted by mammography screening in Copenhagen, Denmark. Population data were retrieved from the Danish Civil Registration System; invitation and attendance data from the screening programme database. Data were linked using unique personal identification numbers. Coverage by invitation was defined as (number of invited women/number of targeted women), coverage by examination as (number of screened women/number of targeted women), and participation rate as (number of screened women/number of invited women).RESULTS:Coverage by invitation was close to or above 95% for all newly recruited cohorts. In subsequent invitation rounds, both technical errors and changes in the invitation scheme affected the coverage by invitation. Coverage by examination at first invitation was 72.5% for the first cohort, but dropped to 64.2% for the latest cohort. Furthermore, coverage by examination dropped by increasing invitation number and with omission of re-invitation of previous non-attenders. Participation rate closely reflected changes in the invitation scheme.CONCLUSION:Changes in the invitation schemes influenced coverage by invitation, coverage by examination, and participation rate. We observed a considerable gap between coverage by examination and participation rate, strongly indicating that the latter cannot without reservations, be taken as an indicator of the first.

U2 - 10.1177/0969141316641982

DO - 10.1177/0969141316641982

M3 - Journal article

C2 - 27206815

VL - 24

SP - 20

EP - 26

JO - Journal of Medical Screening

JF - Journal of Medical Screening

SN - 0969-1413

IS - 1

ER -