Table 6.

Suggestions of participants for images included in the app.

Image category	Health care professionals (n=10)	Inpatient participants (n=5)	Outpatient participants (n=5)
Alcohol	“Picture more relevant to the local context, for example, picture from coffee shop” [Participant 6] Not to focus on the “brands” of the alcohol [Participant 6]	“Hard liquor” was missing [Participants 1 and 2]	No need to include the “brand” of the alcohol [Participant 4] “More kind of hard liquor, such as whisky” [Participant 4]
Cannabis	“Some of the pictures were not familiar” [Participant 2]	A “barrel and aluminum foil” would be good [Participant 3] “Bottles” might not be so relevant, as they are synthetic cannabinoids [Participant 1]	“The bong is not the right bong” [Participant 2]
Heroin	“Straws” “pictures of the barrel and thin foils” [Participant 5] “Someone chasing the dragon, or someone using the main line” are the most relevant and triggering [Participant 3]	“The one with needle” [Participant 4]	“Syringe” image was perceived to be “very triggering” [Participant 1] “Nothing catches my eye except for this needle thing” [Participant 3] Pills “oxycodone” was not used locally (“Singapore people don’t abuse”). [Participant 1]
Stimulants	The images of the stimulant crystals might not be so relevant, as the crystals available locally are “of different quality” [Participant 2]	“Pure image of ICEa” [Participant 1]	“Don’t look like ICE at all” [Participant 4]

^aICE: methamphetamine (stimulant).