Monozygotic shared 100% genetic and environment. Whereas, dizygotic shared 50% genetic and 100% environment (Afari, Buchwald, Dansie, Poeschla & Strachan, 2013). In the past, similar studies was conducted by other researchers to determine if chronic fatigue and chronic fatigue syndrome (CFS) was a primary physical condition or psychological in nature. For examples, CDC conducted a survey of 14,627 individual in a community-based for unexplained fatigue. There were 1.8% of adults found prevalence to be unexplained fatigue and 0.2% was CFS-like illness. This results was consistent with the estimates of prevalence of CSF of 0.007 to 0.56% in community sample and primary care setting (Afari et al., 2013). After decades of studies, the causes of unexplained fatigue remain unknown. Leading to the question, does generic and personality traits play a role in chronic …show more content…
Chronic fatigue was used for individuals that have not been diagnosed with CFS but had the symptoms. CFS was used for individuals that had been diagnosed by the individual’s physician prior to the study. CFS is a complicated medical disorder that characterized by extreme fatigue that is unexplained by any underlying medical condition. Extreme fatigue is not improved by bed rest and is worsened by physical and mental activities. There is no specific diagnostic test to diagnose CFS, the causes are unknown. In 1994, the Centers of Disease Control and Prevention (CDC) developed the standard symptoms for diagnosing CFS. According to CDC, CFS diagnose requires three criteria, first the individual must have the symptoms for six or more in consecutive months, fatigue significantly interferes with daily activities and work, and finally individual must have four or more of the eight symptoms. The eight symptoms are fatigue, loss of memory or concentration, sore throat, swollen glands, unexplained muscles or joint pain without swollen, new headaches, unrefreshing sleep and extreme exhaustion lasting more than twenty-four hours following physical or mental activities (Afari et al., 2013). During clinical examination, including history, physical examination, mental status examination and laboratory testing was done to rule out fatigue as a secondary condition. Includes any clinical depression, eating