Umeki Yuka, Tabuchi Takahiro
Faculty of Medicine, Osaka University.
Cancer Control Center, Osaka International Cancer Institute.
Nihon Koshu Eisei Zasshi. 2021 Dec 24;68(12):914-924. doi: 10.11236/jph.21-051. Epub 2021 Oct 22.
Objectives Exposure to secondhand smoke is harmful to children's health. Therefore, the Tokyo metropolitan area implemented an ordinance on April 1st, 2018 that prohibits smoking in private homes when children are present. To date, the effect of this ordinance has not been studied. In this study, we evaluated the change in the percentage of residents in the Tokyo metropolitan area who have smoke-free household rules using difference-in-difference (DID) analysis.Methods A one year, follow-up, longitudinal internet survey of the general Japanese population was conducted from 2018 to 2019 (Japan Society and New Tobacco Internet Survey, JASTIS). DID analysis was conducted using the percentage of residents who have smoke-free household rules in Tokyo metropolitan area and control groups in 2018 and 2019.Results We utilized three control groups (Control 1: residents in Japan except from Tokyo metropolitan area; Control 2: residents in Japan except from Kanto region; Control 3: residents in prefectures which have ordinance-designated city) for DID analysis. Covariate-adjusted DID estimates for each control group were -1.0 percentage points (Control 1, 95% Confidence Interval (CI)=-5.8, 3.9), -1.0 percentage points (Control 2, 95% CI=-5.9, 4.0), and -1.0 percentage points (Control 3, 95% CI=-5.9, 3.9) indicating that there was no significant difference for all control groups. Moreover, no significant difference was observed when respondents' answers were analyzed and stratified according to sex, age, household income, housing tenure, smoking status, education, or marital status.Conclusions DID analysis revealed no significant change in the percentage of residents of the Tokyo metropolitan area who have smoke-free household rules after the implementation of the ordinance. This study will be useful for local governments when planning and promoting more effective smoke-free ordinances.
目的 接触二手烟对儿童健康有害。因此，东京都于2018年4月1日实施了一项条例，禁止在有儿童在场的私人住宅内吸烟。迄今为止，该条例的效果尚未得到研究。在本研究中，我们使用差分法（DID）分析评估了东京都制定无烟家庭规则的居民比例的变化。
方法 2018年至2019年对日本普通民众进行了为期一年的随访纵向网络调查（日本社会与新烟草网络调查，JASTIS）。使用2018年和2019年东京都和对照组中制定无烟家庭规则的居民比例进行DID分析。
结果 我们使用了三个对照组（对照组1：日本除东京都以外的居民；对照组2：日本除关东地区以外的居民；对照组3：有条例指定城市的县的居民）进行DID分析。每个对照组的协变量调整后的DID估计值为-1.0个百分点（对照组1，95%置信区间（CI）=-5.8，3.9）、-1.0个百分点（对照组2，95%CI=-5.9，4.0）和-1.0个百分点（对照组3，95%CI=-5.9，3.9），表明所有对照组均无显著差异。此外，根据性别、年龄、家庭收入、住房 tenure、吸烟状况、教育程度或婚姻状况对受访者的回答进行分析和分层时，未观察到显著差异。
结论 DID分析显示，该条例实施后，东京都制定无烟家庭规则的居民比例没有显著变化。本研究将有助于地方政府规划和推广更有效的无烟条例。
