Introduction Retesting Chlamydia trachomatis (CT) treated people after 3–12 months is recommended as it can yield substantial numbers of reinfections. A test-of-cure (TOC) shortly after treatment (within 3 months) is not advisable due to the likelihood of false positive findings leading to overtreatment. Spatial analyses are useful to detect geographical areas of low guideline adherence to inform local testing policies and targeted interventions. The aim was to assess geographical variation in test practices of general practitioners (GPs) in The Netherlands.

Methods Retrospective laboratory data containing CT tests of 48 GPs in 4 municipalities were obtained (2011–2015) from the public laboratory in the south western part of the Netherlands (183 thousand residents). First recorded urogenital positive CT tests of men (n=249; 39.2%) and women (n=386;60.8%)≥16 years between January 2011 and July 2015 were included in the analyses and TOC and retests were outcomes. Logistic regression was used for analyses.

Results Overall, 8,275 CT tests were performed (positivity 8.4%;n=691);only 0.4% (n=43) from extra genital sites. On a GP level, the number of CT tests varied geographically from 1 to 2421 (p<0.001). A TOC was performed in 19.1% of the CT cases (n=123;13.8% positive). TOC was more often performed in south Maastricht in comparison with the centre of Maastricht (p=0.02,OR 3.0,95% CI 1.23–7.33). A retest was performed in 23% of the CT cases (n=146;10.3% positive). The rate of retests non-significantly varied geographically between 6.3% and 30.2% p=0.33. Patients with a TOC were more likely to have a retest in comparison with cases without a TOC (p=0.02).

Conclusion Testing at extra genital sites and the overall proportion of retests was low at GP practices. Almost one out of five CT cases returned within three months, and many (re-)infections were probably missed. Moreover, it seems that there are geographical variations in test practices of GPs. Thus, targeted interventions at the local level are needed to increase CT testing and retesting practices of GPs.