Guideline adherence for diagnostic faeces testing in primary care patients with gastroenteritis

Gastroenteritis (GE) is a common reason for primary care consultation. Dutch clinical practice guidelines (CPG) recommend diagnostic faeces testing (DFT) only in primary care patients with severe illness, comprised immunity or increased transmission risk. For its superior accuracy, shorter turnaround time and ease of use, polymerase chain reaction (PCR)-based DFT has largely replaced conventional techniques. It is unknown whether this changed CPG adherence.

To quantify the effect of PCR introduction on adherence to CPG indications for DFT in primary care patients with GE.

We performed a cohort study using routine care data of 225 GPs. Episodes of GE where DFT was performed were extracted from electronic patient records. Presenting symptoms were identified and adherence to CPG indications for DFT assessed in two randomly drawn samples of each 500 patients, one from the period before PCR introduction (2010-11) and one after (2013). The association between PCR introduction and adherence was estimated using multivariable regression analysis.

In 88% of all episodes relevant presenting symptoms were reported, most often 'frequent watery stool' (58%) and 'illness duration >10 days' (40%). DFT was performed in 15% of episodes before PCR introduction and in 18% after. Overall, in 17% the DFT request was considered adherent to the CPG, 16% before PCR introduction and 18% after (adjusted OR 1.2, 95% CI 0.9-1.7).

Overall adherence to CPG indications when requesting DFT in primary care patient with GE was 17%. Implementation of PCR-based DFT was not associated with a change in CPG adherence.