Tripartite Influence Scale (TIS) applied to university students: validation study and application

Abstract: The Tripartite Influence Scale (TIS) is used to assess the influence of social and family factors on individuals’ body image. However, little evidence has been presented on the validity of the TIS construct. The study aimed to estimate the psychometric indicators in TIS and identify the degree of influence of the media, parents, and peers on body image in university students, considering different characteristics. University students of both sexes participated. The psychometric indicators in TIS were assessed for each sex using confirmatory factor analysis. Mean scores were calculated for each TIS factor. Prevalence rates for degree of influence were presented. A multivariate regression model was built to verify the relationship between target characteristics and TIS factor scores. The sample included 791 university students (63.2% women) 18 to 40 years of age. TIS did not initially display a good fit to the samples and was therefore refined. After refinement, the scale showed adequate validity and reliability for women and men. Significant differences were observed in the mean scores between women and men, and in the prevalence rates the majority of the students were in the low category. Work, consumption of food supplements for body changes, age, body mass index, self-rated diet, and level of physical activity were significantly related to TIS factors. Women were generally more influenced than men by the media and peers. Characteristics identified as related to TIS can be relevant for inclusion in clinical and research protocols.

摘要：三方影响量表（Tripartite Influence Scale，TIS）用于评估社会与家庭因素对个体身体意象的影响。然而，目前关于TIS结构效度的实证证据仍较为有限。本研究旨在估算TIS的心理测量学指标，并结合不同人口学特征，明确媒体、父母及同伴对大学生身体意象的影响程度。本研究招募了不同性别的大学生作为被试。采用验证性因素分析分别评估了不同性别群体的TIS心理测量学指标，计算了各TIS因子的平均得分，并呈现了各影响程度的患病率分布。构建了多元回归模型以验证目标特征与TIS因子得分之间的关联。本次研究共纳入791名年龄介于18至40岁的大学生，其中女性占比63.2%。初始版本的TIS与样本数据的拟合度不佳，因此对量表进行了修订。修订后的量表在男女群体中均表现出良好的效度与信度。男女群体在各因子平均得分及影响程度患病率上均存在显著差异，且大部分学生的影响程度处于低水平类别。研究发现，职业状况、用于身体塑形的膳食补充剂摄入情况、年龄、身体质量指数、自我评估饮食状况及身体活动水平均与TIS因子存在显著关联。总体而言，女性受媒体与同伴的影响程度高于男性。本研究识别出的与TIS相关的特征，可为临床实践与研究方案的制定提供重要参考依据。