Drug test strips help prevent drug overdoses. People can use these strips anywhere, and studies show the results actually change behavior — people report not using, using less, or using in ways that are less likely to cause overdose, like with someone nearby (Goldman et al., 2019). Because they are such a valuable tool, it is critical that they work right.
Drug test strips that are marketed for use in drug checking are currently not regulated by FDA or Canada Health Services, so we have started a lot checking project to make sure that these products are fit for this application.
Each dashboard is organized around three levels: manufacturer (the company that actually makes the physical strip, which is not always disclosed and can change over time even for a familiar brand), brand (the name printed on the box, which is how the strip is sold and marketed), and lot (sometimes called a batch: one specific production run, identified by a lot or batch number printed on the packaging).
One manufacturer can sell strips under several different brand names, and one brand accumulates many different lots over time as new batches are produced. That is why a single brand can show up as many separate entries on a dashboard: each row is a lot, not a brand, and lot-to-lot quality can vary even within the same brand. Testing at the lot level, not just the brand level, is the whole point of this project.
In practice this means if the strip says it's there, it's probably there — but if the strip can't detect the target, there could still be a small amount of the target or a different structural variation. If you prepare samples using a standard 2 mg/mL nominal concentration (e.g., 10 mg scoop + 5 mL water) these results should be reliable.