Diagnostic intervals before and after implementation of cancer patient pathways - a GP survey and registry based comparison of three cohorts of cancer patients

Background: From 2008, Danish general practitioners could refer patients suspected of having cancer to standardised cancer patient pathways (CPPs). We aimed to compare the length of the diagnostic interval in 2010 with the length of the diagnostic interval before (2004/05) and during (2007/08) the implementation of CPPs in Denmark for all incident cancer patients who attended general practice prior to the cancer diagnosis. Methods: General practitioner questionnaires and register data on 12,558 patients were used to compare adjusted diagnostic interval across time by quantile regression. Results: The median diagnostic interval was 14 (95% CI: 11; 16) days shorter during and 17 (95% CI: 15; 19) days shorter after the implementation of CPPs than before. The diagnostic interval was 15 (95% CI: 12; 17) days shorter for patients referred to a CPP in 2010 than during the implementation, whereas patients not referred to a CPP in 2010 had a 4 (95% CI: 1; 7) days longer median diagnostic interval; the pattern was similar, but larger at the 75th and 90th percentiles. Conclusion: The diagnostic interval was significantly lower after CPP implementation. Yet, patients not referred to a CPP in 2010 tended to have a longer diagnostic interval compared to during the implementation. CPPs may thus only seem to expedite the diagnostic process for some cancer patients.