INTRODUCTION: It is held that younger smoking initiates are more likely to become regular smokers. The definitions of smoking initiation (a puff, part of a cigarette, a whole cigarette) are inconsistent and raise questions about the robustness of the view. We sought to re-examine the relationship using adolescent smoking data from 3 European countries.
METHODS: A stratified secondary, logistic regression analysis of Global Youth Tobacco Survey data was conducted using a design-based analysis. Subgroup analyses were conducted of 13- to 15-year olds from Latvia (high smoking prevalence), Slovenia (moderate prevalence), and Montenegro (low prevalence) who had initiated smoking. The outcome was current smoking--smoking everyday for the past 30 days, or smoking 10 or more days in the past 30 days. Smoking initiation was operationalized as a single puff of a cigarette, and age of smoking initiation was a derived continuous measure.
RESULTS: In Latvia, there was a significant association between age of smoking initiation and current smoking for males (p < .05) and females (p < .001) when smoking was operationalized as smoking every day. It was only significant in female adolescents (p < .001) for smoking 10 or more days. In Slovenia and Montenegro, there was no significant relationship between age of smoking initiation and current smoking for either males or females.
CONCLUSIONS: The evidence about the relationship between age of smoking initiation and current smoking is not clear. Explanations for the findings may relate to a lack of power, the specificity of the measure, or problems with the theory.
The Standard DAI is an orthodontic index based on perceptions of dental aesthetics in the USA. The Standard DAI is a regression equation linking perceptions of the social acceptability of dental aesthetics with the objective intraoral measurements of ten occlusal traits. Since the Standard DAI is based on perceptions of dental aesthetics in the USA it can be used without modification only where perceptions of dental aesthetics are similar to those in the USA. This study was designed to determine whether perceptions of dental aesthetics of students in eleven diverse ethnic groups are similar to those of students in the USA. The same 25 stimuli (photographs of dental configurations, a subset of the 200 stimuli used in deriving the Standard DAI equation) were rated for dental aesthetics by Australian, Chinese, German, Japanese, Korean, Latvian, Native American, Singaporean Chinese, Singaporean Indian, Singaporean Malay, and Thai students. Their ratings were compared with the ratings of the same 25 stimuli by students in the USA. Spearman rank-order correlations ranged from 0.84 to 0.94. These correlations are sufficiently high to show that perceptions of dental aesthetics in all eleven ethnic groups are very similar to the perceptions of USA students. Therefore the Standard DAI can be used without modification in all eleven ethnic groups.