BMC Cancer 2008, 8:355 http://www.biomedcentral.com/1471-2407/8/355 1.0 0.9 0.8 y0.7 t i l i b0.6 a b o rp0.5 l a iv0.4 v r u S0.3 0.2 0.1 0.0 0 5 10 Year of follow-up 15 20 dFCeiogslcuoerunertv1deirasginoons:eKda1p9la8n0-–M8e7iearneds1ti9m9a6t–e2o0f0s5ufrovlilvoawlceudruvep ounftlyilm1p2h/2o0id06leukaemia (ICCC3 Ia), cases with and without Turkish Colour version: Kaplan-Meier estimate of survival curve of lymphoid leukaemia (ICCC3 Ia), cases with and without Turkish descent diagnosed 1980–87 and 1996–2005 followed up until 12/2006. Black line: non-Turkish cases diagnosed 1996–2005 (507 events/4559 cases). Blue line: Turkish cases diagnosed 1996–2005 (32 events/265 cases). Grey line: non-Turkish cases diagnosed 1980–87 (719 events/2361 cases). Light blue line: Turkish cases diagnosed 1980–87 (52 events/105 cases). leukaemia. The available data offer little clues why this difference occurred. So far we have no indication that incomplete reporting in the early 1980s was related to prognosis or migrant status, but a selection bias cannot be entirely excluded. Given the large number of statistical comparisons we performed, chance may be among the possible explanations. Problems that could be associated with e.g. a language barrier, such as parental compliance with therapy recommendations, appear unlikely, but may have played a role in certain specific diagnoses with ther- apeutic regimen that require long-term care after the ini- tial therapy. There are, however, no recorded data to further assess this hypothesis. Socioeconomic status did not change very much for Turkish migrant groups over the time period investigated, neither did access to medical care, especially for children. Most of these potential explanatory factors would also have affected all diagnoses to the same degree. More important are the recent results showing very similar survival probabilities in the groups compared. The actual survival estimates for the most recent period may be overestimated for all cases due to incomplete follow-up. Page 5 of 7 (page number not for citation purposes)