Faculdade de Ciências da Saúde, Universidade da Beira Interior, Covilhã, Portugal.
Br J Health Psychol. 2011 Nov;16(4):779-98. doi: 10.1111/j.2044-8287.2010.02014.x. Epub 2011 Jan 13.
There is a debate on the determinants of smoking behaviour, their relative impact, and how impacts are exerted. This longitudinal study is on the relations among social influence, intention to smoke, and smoking behaviour, controlling for attitude and self-efficacy.
A model combining parents and peers with subjective and descriptive norms, resulting in four factors, was used to assess social influence. Data were collected at the beginning of the 7th(-T1), 8th(-T2), and 9th(-T3) school years, concerning 578 students (M(age) = 13.04 at T1). Structural Equation Modelling was used to test longitudinal effects.
Variances explained by the model were high: R(2) (intention-T2) = .65, R(2) (behaviour-T2) = .67, and R(2) (behaviour-T3) = .76. Longitudinal analyses confirmed the effects of social influence on intention and behaviour. These effects on behaviour were direct and indirect (peers' and parents' descriptive norms in both cases). Descriptive norms had a stronger effect on behaviour than subjective norms. Peers' effect on behaviour was stronger than parents', but peers' effect was exerted only through descriptive norms while parents' effect was exerted through both norms. The intention effect on behaviour was not as detached as expected and its role of full mediator between other variables' effects on behaviour was not confirmed, since descriptive norms and self-efficacy had also a mediation role.
Results show direct and indirect effects of social influence on behaviour. Descriptive norms are an important variable to operationalize social influence. Peers and parents exert influence on adolescents' intention and behaviour through different processes. The impact of intention on behaviour is not as important as expected.
关于吸烟行为的决定因素、它们的相对影响以及影响的施加方式，存在争议。本纵向研究关注社会影响、吸烟意向和吸烟行为之间的关系，同时控制态度和自我效能感。
使用结合了父母和同伴的主观和描述性规范的模型，产生了四个因素，来评估社会影响。数据是在 7 年级（T1）、8 年级（T2）和 9 年级（T3）开始时收集的，涉及 578 名学生（T1 时的平均年龄为 13.04 岁）。结构方程模型用于测试纵向效应。
模型解释的方差很高：意向（T2）的 R²=.65，行为（T2）的 R²=.67，行为（T3）的 R²=.76。纵向分析证实了社会影响对意向和行为的影响。这些对行为的影响是直接的和间接的（在两种情况下，同伴和父母的描述性规范）。描述性规范对行为的影响比主观规范更强。同伴对行为的影响大于父母，但同伴的影响仅通过描述性规范施加，而父母的影响则通过两种规范施加。意向对行为的影响并不像预期的那样独立，并且其作为其他变量对行为影响的完全中介作用也没有得到证实，因为描述性规范和自我效能感也具有中介作用。
结果表明社会影响对行为有直接和间接的影响。描述性规范是操作社会影响的重要变量。同伴和父母通过不同的过程对青少年的意向和行为施加影响。意向对行为的影响并不像预期的那样重要。
