Yue-Fang Chang, PhDResearch Assistant Professor of Neurological Surgery
Yue-Fang Chang, PhD, joined the Department of Neurological Surgery as a research associate in June of 2000. She received her doctoral degree in statistics from the University of Illinois and master degree in epidemiology from the University of Pittsburgh.
Dr. Chang has worked in a variety of areas, such as brain tumor, traumatic brain injury, health outcome, image study, women’s health and diabetes epidemiology. She serves as the lead statistician in several epidemiological studies including Cardiovascular Health Study, Women’s Health Initiative and Study of Women’s Health Across the Nation. In the past ten years she has been involved in numerous grant preparations, providing statistical expertise in design, analysis and power/sample size calculations.
Dr. Chang's publications can be reviewed through the National Library of Medicine's publication database.
1) Women’s Health Across the Nation—SWAN:
This study identifies and validates reliable markers of the transition in menopausal status and describes their normal variation in a multi-ethnic cohort of mid-aged women. Dr. Chang examines the relation among anxiety syndrome, menopausal status, vasomotor symptom and other factors. Anxiety syndrome is more strongly related to vasomotor symptom than to the menopausal transition. This suggests that vasomotor symptom likely explains the association of not only anxiety symptoms, but an anxiety syndrome with menopausal stage.
2) Predictors of Alzheimers Disease in Mild Cognitive Impairment
The objective of this study is to support the central hypothesis that the patholigcal state of AD exists years prior to the development of the clinical signs/symptoms of the dementia syndrome. Dr. Chang examined the incidence of mild cognitive impairment (MCI) and patterns of progression from incident MCI to dementia in cognitively normal subjects. The majority of the subjects age >80 developed an MCI syndrome and half of them progressed to dementia. Importantly, once the MCI syndrome is present, the symptoms of dementia appear within 2-3 years. Progression from normal to MCI or from normal to MCI to dementia is not always linear. Competing mortality and morbidity are inevitable factors that influence the study of incident MCI and dementia in population cohorts.
3) Epidemiology of Cardiovascular Risk Factors in Women
The primary focus of this study is to measure the progression of coronary calcium in women who had some calcification previously and the development of coronary calcium in women who had none and to investigate the relationship of coronary calcification to pre- and post -menopausal risk factors. Identification of early and modifiable risk factors for subclinical disease should lead to reduction of clinical cardiovascular disease among postmenopausal women.
4) Epidemiology of Diabetes Complication: Phase III
This project examines the prevalence and incidence of and risk factors contributing to diabetes complications for 24 years. Dr. Chang has studied the time course of HbA1c and insulin dose in individuals who either develop, or who remained free of, CAD during follow-up period. The patterns observed suggest that the development of CAD is associated with the combination of declining glycemic control and insulin dose.