Despite the widespread use of exploratory factor analysis in psychological research, researchers often make questionable decisions when conducting these analyses. This article reviews the major design and analytical decisions that must be made when conducting a factor analysis and notes that each of these decisions has important consequences for the obtained results. Recommendations that have been made in the methodological literature are discussed. Analyses of 3 existing empirical data sets are used to illustrate how questionable decisions in conducting factor analyses can yield problematic results. The article presents a survey of 2 prominent journals that suggests that researchers routinely conduct analyses using such questionable methods. The implications of these practices for psychological research are discussed, and the reasons for current practices are reviewed.

No abstract

No abstract

Objective: To outline social psychological principles that could influence the psychosocial and behavioural effects of tobacco warning labels, and to inform the development of more effective tobacco warning labels. Data sources: PsycInfo and Medline literature searches and expert guided selection of principles and theories in social psychology and of tobacco warning labels, including articles, books, and reports. Conclusions: Tobacco warning labels represent a potentially effective method of influencing attitudes and behaviours. This review describes social psychological principles that could be used to guide the creation of more effective warning labels. The potential value of incorporating warning labels into a broader public health education campaign is discussed, and directions for future research are suggested.

No abstract