Alcohol Treatment Center, Department of Community Medicine and Health, Centre Hospitalier Universitaire Vaudois, Beaumont 21b, P2, Lausanne, CHUV 1011, Switzerland.
Addict Sci Clin Pract. 2013 Oct 19;8(1):15. doi: 10.1186/1940-0640-8-15.
Interventions have been developed to reduce overestimations of substance use among others, especially for alcohol and among students. Nevertheless, there is a lack of knowledge on misperceptions of use for substances other than alcohol. We studied the prevalence of misperceptions of use for tobacco, cannabis, and alcohol and whether the perception of tobacco, cannabis, and alcohol use by others is associated with one's own use.
Participants (n=5216) in a cohort study from a census of 20-year-old men (N=11,819) estimated the prevalence of tobacco and cannabis use among peers of the same age and sex and the percentage of their peers drinking more alcohol than they did. Using the census data, we determined whether participants overestimated, accurately estimated, or underestimated substance use by others. Regression models were used to compare substance use by those who overestimated or underestimated peer substance with those who accurately estimated peer use. Other variables included in the analyses were the presence of close friends with alcohol or other drug problems and family history of substance use.
Tobacco use by others was overestimated by 46.1% and accurately estimated by 37.3% of participants. Cannabis use by others was overestimated by 21.8% and accurately estimated by 31.6% of participants. Alcohol use by others was overestimated by more than half (53.4%) of participants and accurately estimated by 31.0%. In multivariable models, compared with participants who accurately estimated tobacco use by others, those who overestimated it reported smoking more cigarettes per week (incidence rate ratio [IRR] [95% CI], 1.17 [range, 1.05, 1.32]). There was no difference in the number of cigarettes smoked per week between those underestimating and those accurately estimating tobacco use by others (IRR [95% CI], 0.99 [range, 0.84, 1.17]). Compared with participants accurately estimating cannabis use by others, those who overestimated it reported more days of cannabis use per month (IRR [95% CI], 1.43 [range, 1.21, 1.70]), whereas those who underestimated it reported fewer days of cannabis use per month (IRR [95% CI], 0.62 [range, 0.23, 0.75]). Compared with participants accurately estimating alcohol use by others, those who overestimated it reported consuming more drinks per week (IRR [95% CI], 1.57 [range, 1.43, 1.72]), whereas those who underestimated it reported consuming fewer drinks per week (IRR [95% CI], 0.41 [range, 0.34, 0.50]).
Perceptions of substance use by others are associated with one's own use. In particular, overestimating use by others is frequent among young men and is associated with one's own greater consumption. This association is independent of the substance use environment, indicating that, even in the case of proximity to a heavy-usage group, perception of use by others may influence one's own use. If preventive interventions are to be based on normative feedback, and their aim is to reduce overestimations of use by others, then the prevalence of overestimation indicates that they may be of benefit to roughly half the population; or, in the case of cannabis, to as few as 20%. Such interventions should take into account differing strengths of association across substances.
已经开发出干预措施来减少对物质使用的高估，特别是对酒精的高估，以及对学生的高估。然而，对于除酒精以外的物质的使用的误解仍然缺乏了解。我们研究了对烟草、大麻和酒精使用的误解的流行程度，以及对他人使用烟草、大麻和酒精的看法是否与自己的使用有关。
我们对一项来自 20 岁男性（n=11819）普查的队列研究中的参与者（n=5216）估计了同龄同性别的同龄人中烟草和大麻的使用情况，以及他们饮酒量超过自己的同龄人比例。使用普查数据，我们确定参与者是否高估、准确估计或低估了他人的物质使用情况。回归模型用于比较高估或低估同伴物质使用的参与者与准确估计同伴使用的参与者之间的物质使用情况。分析中还包括其他变量，如是否有酗酒或其他药物问题的亲密朋友以及家族物质使用史。
46.1%的参与者高估了他人的烟草使用情况，37.3%的参与者准确估计了他人的烟草使用情况。21.8%的参与者高估了他人的大麻使用情况，31.6%的参与者准确估计了他人的大麻使用情况。超过一半（53.4%）的参与者高估了他人的酒精使用情况，31.0%的参与者准确估计了他人的酒精使用情况。在多变量模型中，与准确估计他人烟草使用情况的参与者相比，高估者报告每周吸烟量（发病率比[IRR] [95%置信区间]，1.17 [范围，1.05，1.32]）更高。低估者与准确估计他人烟草使用情况的参与者之间每周吸烟量没有差异（IRR [95% CI]，0.99 [范围，0.84, 1.17]）。与准确估计他人大麻使用情况的参与者相比，高估者报告每月大麻使用天数更多（IRR [95% CI]，1.43 [范围，1.21, 1.70]），而低估者报告每月大麻使用天数更少（IRR [95% CI]，0.62 [范围，0.23, 0.75]）。与准确估计他人酒精使用情况的参与者相比，高估者报告每周饮酒量更多（IRR [95% CI]，1.57 [范围，1.43, 1.72]），而低估者报告每周饮酒量更少（IRR [95% CI]，0.41 [范围，0.34, 0.50]）。
对他人物质使用的看法与自己的使用有关。特别是，年轻人中高估他人使用的情况很常见，并且与自己的消费增加有关。这种关联独立于物质使用环境，表明即使在接近高使用率群体的情况下，对他人使用的看法也可能影响自己的使用。如果预防干预措施基于规范反馈，并且其目的是减少对他人使用的高估，那么高估的流行程度表明，大约一半的人口可能从中受益；或者在大麻的情况下，可能只有 20%的人口受益。这些干预措施应该考虑到不同物质之间关联的强弱。
