Household size related to prevalence of smoking in women in Japan.

We investigated the relationship between the prevalence of smoking in females and various social factors, such as household size. Ten thousand and sixty-nine subjects over 20 years of age were randomly selected from the general population of Mie Prefecture. The results showed that the habit of smoking was significantly associated with household size in women (P< 0.01), but not in men. Regarding household size, current smoking rate of women aged 20-59 who live in three-generation household was lower than those who live in others. Therefore, the steady replacement of the traditional three-generation household by smaller households in Japan may lead to an increase in the number of young women who smoke.