Rising incidence of XXXX after completion of the first prevalent round of the @entity0 screening programme.

@entity5 @entity0
OBJECTIVES: After completion of the prevalent screening round of the @entity0 screening programme in Limburg, The Netherlands, incidences started rising once again. This increase was contrary to expectations, which had predicted a slightly higher, but stable, incidence after the first screening round. The trends in incidence were studied to find explanations for the observed rise in incidence. SETTING: @entity0 screening programme in mid-Limburg and southern Limburg, the Netherlands. METHODS: The data files of the @entity0 screening programme and the @entity5 registry were linked to evaluate the effect of @entity0 screening. Only the first primary @entity0 was included in the evaluation. RESULTS: The second peak of incidence after the prevalent screening round was 45% higher than the incidences before the start of the screening. Also, the decrease in incidence of large and node positive @entity5 was interrupted. Compared with national detection rates, the number of screen detected @entity5 was lower before 1995 and higher after that year. After 1997, incidence @entity0 , but also of large and node positive @entity5 . The incidence of node positive @entity5 showed large fluctuations, probably due to the introduction of the sentinel node procedure and immunohistochemistry. In 1999, incidence of large @entity5 and node positive @entity5 was 18% and 28%, respectively, lower than before the start of the screening. CONCLUSIONS: An increase in the background incidences and improved detection in the screening programme most likely explain this trend. The improved detection after 1995, and the lower than desirable decrease in large @entity5 , indicate that the screening performance was not optimal before 1996. The incidence of node positive @entity5 cannot be used any more as an indicator of the success of the screening programme because of detection bias.
