Chow 2015.

Methods	Country: China Setting: 'Lab' experiment conducted with Chinese non‐smoking students in Macau Date: unknown Design:Between‐participants experiment with a 2 (label type: existing vs plain packaging) × 2 (brand familiarity: familiar vs unfamiliar brand) factorial design to investigate the effects of this new cigarette labelling format on smoking intent and brand likability among young people
Participants	The sample comprised 116 non‐smoking students aged 18 ‐ 22, 58 percent of them women, studying on the same programme and course at a university in Macau Part of a course curriculum in classroom in a university in China (took place during their normal lectures) 18 ‐ 22 years, average age unknown 42% (n = 49) men, 58% (n = 67) women 100% non‐smokers
Interventions	IV: 2x2 factorial design (packaging and brand familiarity) Branded: Among the 2 treatment conditions that showed the existing packaging, 1 was with a familiar brand “Marlboro” which accounted for more than 50% market share and the other was with an unfamiliar brand “Taipan” which accounted for only a minimal market share and a limited distribution. 50/50 split between the brand message and government message, with the government message in the text‐plus‐graphic format Standardised: Familiar brand Marlboro vs unfamiliar brand Taipan both on standardised packaging
Outcomes	[Secondary non‐behavioural]: smoking intent and the brand’s likability. Brand likability was assessed with a single statement concerning how much they disliked the brand as a result of the packaging: This packaging makes you dislike the cigarette brand. Smoking intent was measured by the participating students’ responses to 3 statements ranked on a 9‐point Likert scale Analysis summary: A lab experiment with a 2 (label: existing versus plain packaging format) × 2 (brand familiarity: familiar vs unfamiliar brand) factorial design. During their normal lectures, students in the different treatment cells were first presented with pictures showing different cigarette‐pack labelling designs, and then instructed to complete a questionnaire measuring their smoking intent and the brand’s likability. The 4 treatments (i.e. 2×2 different cigarette packs) were randomly assigned to students. Survey completed immediately after experiment. Label type is the predictor and 'brand familiarity' is being used as a mediator
Funding source	None provided
Conflicts of interest	None provided
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Selective reporting (reporting bias)	Low risk	Quote: "The sample comprised 116 non‐smoking students aged 18‐22, 58 percent of them female, studying on the same program and course at a university in Macau." Comment: Clearly set out hypotheses which were reported on in the results
Sampling Method	High risk	Comment: Convenience sample
Measurement of independent variable	Low risk	Quote: "Before analyzing the data, we had to ensure that the four treatments had been successfully imposed on subjects through the manipulation." Comment: the authors tested whether the brands were distinguishable in the way intended and they were
Measurement of dependent variable	Low risk	Quote: "These statements were developed from the study done by Sabbane et al. (2009a, b), but required significant adaptation in accordance with the results of a focus group due to the very different context of our experiment." Comment: The questions were based on previous research and a local focus group
Control for confounding	Low risk	Comment: The authors tried to control for confounders in the design of their study
Statistical methods	Low risk	Comment: Appropriate