style (or explanatory style) is a concept introduced by Lyn Yvonne Abramson, Martin Seligman and John D. Teasdale. This concept advances a stage further than Weiner, stating that in addition to the concepts of internality-externality and stability a dimension of globality-specificity is also needed. Abramson et al. believed that how people explained successes and failures in their lives related to whether they attributed these to internal or external factors, short-term or long-term factors, and factors that affected all situations. The topic of attribution theory (introduced to psychology by Fritz Heider) has had an influence on locus of control theory, but there are important historical differences between the two models. Attribution theorists have been predominantly social psychologists, concerned with the general processes characterizing how and why people make the attributions they do, whereas locus of control theorists have been concerned with individual differences. Significant to the history of both approaches are the contributions made by Bernard Weiner in the 1970s. Before this time, attribution theorists and locus of control theorists had been largely concerned with divisions into external and internal loci of causality. Weiner added the dimension of stability-instability (and later controllability), indicating how a cause could be perceived as having been internal to a person yet still beyond the person's control. The stability dimension added to the understanding of why people succeed or fail after such outcomes. Applications Locus of control's best known application may have been in the area of health psychology, largely due to the work of Kenneth Wallston. Scales to measure locus of control in the health domain were reviewed by Furnham and Steele in 1993. The best-known are the Health Locus of Control Scale and the Multidimensional Health Locus of Control Scale, or MHLC. The latter scale is based on the idea (echoing Levenson's earlier work) that health may be attributed to three sources: internal factors (such as self-determination of a healthy lifestyle), powerful others (such as one's doctor) or luck (which is very dangerous as lifestyle advice will be ignored – these people are very difficult to help). Some of the scales reviewed by Furnham and Steele (1993) relate to health in more specific domains, such as obesity (for example, Saltzer's (1982) Weight Locus of Control Scale or Stotland and Zuroff's (1990) Dieting Beliefs Scale), mental health (such as Wood and Letak's (1982) Mental Health Locus of Control Scale or the Depression Locus of Control