Table 7.

Suggested sentinel groups for falsified medicines.

Sentinel group	Definition	Signals potential problem of	Rationale
High irrational demand	Medicines that are used for recreation or other off-label purposes, for which alternatives are restricted or expensive; randomly sampled from retail outlets	Market opportunity	Demand planning is based on authorized uses only. Off-label use creates shortages, which provide market opportunities for falsifiers. Sample frame may be weighted toward independent pharmacies and medicine shops.
Life-saving but unaffordable	Medicines that are known or reputed to be life-saving, that retail at >10% of average per capita household spending, but that are not covered by national insurers; brand-specific sample from retail outlets	Market opportunity	Patients with life-threatening conditions are highly motivated to acquire these medicines. High profit margins incentivize their sale, which may diminish due diligence even in the regulated supply chain. This sample may include products not locally authorized; these should also be screened for falsification.
Sold on unregulated internet platforms	Random sample of “prescription-only” medicines sold through unlicensed internet sellers (sentinel group may be combined with signals of profit potential though purposive sampling of brands retailing at >200% of market median for the dosage form)	Evasion of regulation	Falsifiers favor internet sales because the potential for detection and successful prosecution is low. While the sample may be weighted toward medicines with high irrational demand, it should include other medicines of public health importance, such as antibiotics.