Table 1 Constructs and items

Intention to smoke waterpipe [59]

ITSW1

I intend to continue smoking waterpipe.

ITSW2

I will buy waterpipe if I happened to see it in a store, café, lounge, or restaurant.

ITSW3

I will actively seek out waterpipe in a store, café, lounge, or restaurant to purchase it.

ITSW4

I will patronise waterpipe as a tobacco smoking product.

Positive evaluations of waterpipe (Self-developed)

PEOW1

Waterpipe smoking is attractive.

PEOW2

Waterpipe smoking is fun.

PEOW3

Waterpipe smoking is relaxing.

PEOW4

Waterpipe smoking is romantic.

PEOW5

Waterpipe smoking offers enjoyable fruity flavours.

PEOW6

Waterpipe smoking is more acceptable in the society compared to other methods of tobacco smoking.

PEOW7

Waterpipe smoking is less addictive compared to other methods of tobacco smoking.

PEOW8

Waterpipe smoking is less harmful compared to other methods of tobacco smoking.

PEOW9

In general, I have favourable opinion on waterpipe smoking.

Impulsivity to smoke waterpipe [60]

IMP1

I often smoke waterpipe spontaneously.

IMP2

“Just do it” describes the way I smoke waterpipe.

IMP3

I often smoke waterpipe without thinking.

IMP4

“I see waterpipe, I smoke it” describes me.

IMP5

“Smoke waterpipe now, think about it later” describes me.

IMP6

Sometimes I feel like smoking waterpipe on the spur of the moment.

IMP7

I smoke waterpipe according to how I feel at the moment.

IMP8

I carefully plan most of my waterpipe smoking sessions. (R)

IMP9

Sometimes, I am a bit reckless about waterpipe smoking.

Social media normalisation of waterpipe (Self-developed)

SMNW1

In the past 6 months, I have regularly seen pictures, videos, or other pro-smoking content promoting the use of waterpipe on social media (e.g., Facebook, Instagram, YouTube, Twitter, Tik-Tok, etc.).

SMNW2

In the past 6 months, I have regularly commented positively, reposted, or clicked like on pictures, videos, or other pro-smoking content promoting the use of waterpipe on social media (e.g., Facebook, Instagram, YouTube, Twitter, Tik-Tok, etc.).

SMNW3

Pro-smoking waterpipe messages on social media makes me feel like waterpipe smoking is normal.

SMNW4

Pro-smoking waterpipe messages on social media makes me want to smoke waterpipe.

SMNW5

Pro-smoking waterpipe messages on social media can make people choose waterpipe as a tobacco smoking alternative.

SMNW6

Pro-smoking waterpipe messages on social media can make people want to smoke waterpipe.