claimed self-handicaps are used by men and women alike, several studies have reported significant differences. While research assessing differences in reported self-handicapping have revealed no gender differences or greater self-handicapping among females, the vast majority of research suggests that males are more inclined to behaviourally self-handicap. These differences are further explained by the different value men and women ascribe to the concept of effort. Major theoretical approaches The root of research on the act of self-handicapping can be traced back to Adler's studies about self-esteem. In the late 1950s, Goffman and Heider published research concerning the manipulation of outward behavior for the purpose of impression management. It was not until 30 years later that self-handicapping behavior was attributed to internal factors. Until this point, self-handicapping only encompassed the usage of external factors, such as alcohol and drugs. Self-handicapping is usually studied in an experimental setting, but is sometimes studied in an observational environment. Previous research has established that self-handicapping is motivated by uncertainty about one's ability or, more generally, anticipated threats to self-esteem. Self-handicapping can be exacerbated by self-presentational concerns but also occurs in situations where such concerns are at a minimum. Major empirical findings Experiments on self-handicapping have depicted the reasons why people self-handicap and the effects that it has on those people. Self-handicapping has been observed in both laboratory and real world settings. Studying the psychological and physical effects of self-handicapping has allowed researchers to witness the dramatic effects that it has on attitude and performance. Jones and Berglas gave people positive feedback following a problem-solving test, regardless of actual performance. Half the participants had been given fairly easy problems, while the others were given difficult problems. Participants were then given the choice between a "performance-enhancing drug" and a drug that would inhibit it. Those participants who received the difficult problems were more likely to choose the impairing drug, and participants who faced easy problems were more likely to choose the enhancing drug. It is argued that the participants presented with hard problems, believing that their success had been due to chance, chose the impairing drug because they were looking for an external attribution (what might be called an "excuse") for expected poor performance in the future, as opposed to an internal attribution. More recent research finds that, generally, people are willing to use handicaps to protect their self-esteem (e.g., discounting failings) but are more reluctant to employ