Does diagnostic testing always decrease antibiotics prescriptions?

Empiric prescription to treat infectious diseases in community care settings has caused antibiotics to be overprescribed, increasing antimicrobial resistance (AMR). To reduce antibiotics prescription, the use of point-of-care diagnostic testing (POCT) has been suggested.

We present a stylized static theoretical economic model to analyse whether the use of POCT always decreases antibiotics prescriptions. We consider the interaction of a group of doctors who differ in their level of concern about AMR when prescribing with a firm selling a POCT, and we characterize the price set by the manufacturer and doctors' decision to employ POCT.

We found that the number of antibiotics prescriptions is not always lower. This result depends on the distribution of the doctors' concern about AMR as there is a proportion of doctors who use POCT and then prescribe antibiotics while other doctors change their prescribing behaviour after using POCT and stop giving antibiotics to patients who do not benefit from them. When the proportion of patients who need antibiotic treatment is higher than the proportion of doctors who use POCT and stop prescribing unnecessary antibiotics, the number of antibiotics prescriptions is larger. Our analysis also shows that the use of POCT improves health outcomes.

We should be very careful when we assert that POCT reduces antibiotics prescriptions as there are situations in which the opposite effect occurs.