Table 8.

Summary of the drug abuse ontology implemented in projects.

Domain	Related publications	Manuscript section	Data type	Findings reference
Buprenorphine, loperamide, other opioids	Cameron et al [26], Daniulaityte et al [25,82]	PREDOSEa [26]	Web forum data	Figures 4 and 5
User types in marijuana-related posts on social media	Kursuncu et al [28], Lamy et al [31]	eDrugTrends [28-31,96]	Twitter data, web forums, and Bluelight	Table 2
Depression DSM-5	Gaur et al [41]	eDrugTrends [45]	Web forums, Reddit, and Twitter	Tables 3 and 4
Fentanyl, fentanyl analogs, Clustering of dark web vendors	Usha et al [35], Kumar et al [33], Lamy et al [34]	eDarkTrends [46]	Social media and cryptomarket	Tables 5 and 6
COVID-19	Gaur et al [53,88]	COVID-19: public health study [97]	Social media	Figure 10; Table 7

^aPREDOSE: Prescription Drug Abuse Online Surveillance.