An example method includes: analyzing a clot curve for a test sample that is based on an assay performed on the test sample in order to obtain two or more parameters associated with the clot curve; analyzing the two or more parameters to determine at least one of (i) whether a fibrinogen concentration in the test sample is below a threshold, or (ii) whether there is a therapeutic or pharmaceutical anticoagulant present in the test sample; and outputting, to a user interface, information based on the determination.