Effects of cigarette price and packaging on hypothetical quit-smoking behaviour: a discrete choice experiment among Vietnamese adults who smoke.

Abstract

Introduction: Raising cigarette prices, increasing graphic health warning label (HWL) coverage and requiring plain packaging could reduce cigarette smoking in Vietnam. This discrete choice experiment estimates the potential impact of these policies on smoking behaviour.

Methods: In February-May 2022, we conducted a phone-based, cross-sectional survey of 1494 Vietnamese adults who smoke. Participants were randomly assigned to view four individual cigarette pack images, varied on price (15 000 (reference group); 20 000; 30 000 or 40 000 Vietnamese dong (VND)) and packaging (branded pack with 50% graphic HWL (reference group); branded pack with 85% graphic HWL; plain pack with 50% graphic HWL or branded pack without HWL). Participants responded if they would quit or continue smoking if they could only purchase the pack shown. We used binomial logistic regressions to estimate the relative risk (RR) of price and packaging on hypothetical quitting.

Results: Participants were more likely to report they would quit when presented with 30 000 VND (RR 1.20, 95% CI 1.07 to 1.35) and 40 000 VND packs (RR 1.40, 95% CI 1.23 to 1.58) vs the 15 000 VND pack. Participants were also more likely to report they would quit when shown the branded pack with 85% HWL (RR 1.30, 95% CI 1.18 to 1.42) and plain pack with 50% HWL (RR 1.34, 95% CI 1.21 to 1.49) vs the branded pack with 50% HWL coverage. Participants had significantly lower quit likelihood (RR 0.41, 95% CI 0.35 to 0.48) when shown the branded pack without a HWL.

Conclusions: Results suggest raising cigarette prices to at least 30 000 VND, implementing larger graphic HWLs or plain packaging could decrease smoking rates in Vietnam.