Inverted items and validity: A psychobiological evaluation of two measures of psychological resources and one depression scale.

ABSTRACT

Psychological resources and risk factors influence risk of coronary heart disease. We evaluated whether inverted items in the Self-esteem, Mastery, and Center for Epidemiological Studies Depression scales compromise validity in the context of coronary heart disease. In a population-based sample, validity was investigated by calculating correlations with other scales (n = 1004) and interleukin-6 (n = 374), and by analyzing the relationship with 8-year coronary heart disease risk (n = 1000). Negative items did not affect the validity of the resource scales. In contrast, positive items from Center for Epidemiological Studies Depression showed no significant relationships with biological variables. However, they had no major impact on the validity of the original scale.