Epidemiology of LBPLBP is an important health problem in both developed and developing countries (Brooks, 2006;Woolf & Pfleger 2003). LBP results in socio-economic losses, health and clinical problems, not only for individuals but also for countries, because LBP causes obstacles to work or work absence and increases economic burden of treatment and compensation. Therefore, epidemiological study holds an important position in understanding LBP.Epidemiology is the study of the health of human populations. Its functions are:www.intechopen.com Low Back Pain 4 1. To discover the agent, host, and environmental factors which affect health, in order to provide the scientific basis for the prevention of disease and injury, and the promotion of health. 2. To determine the relative importance of causes of illness, disability, and death, in order to establish priorities for research and action. 3. To identify those sections of the population which have the greatest risk from specific causes of ill health, in order that the indicated action may be directed appropriately. 4. To evaluate the effectiveness of health programs and services in improving the health of the population. (Brownson, 1998).In the case of LBP, epidemiology investigates the various factors of LBP included in the risk factors for LBP, the effects of prevention measures and interventions on LBP, the interaction of risk factors for LBP, time course changes of LBP, the burden of LBP, associations among this information and so on. Much epidemiological research on LBP has been conducted worldwide. This research is important in understanding the past, present and future of LBP, and epidemiological data provide much information to assist in seeking and solving the various problems related to LBP. Moreover, these data can prevent LBP by avoiding or decreasing risk factors for individuals.The two most basic concepts of epidemiology are incidence and prevalence. Incidence is defined as the rate at which healthy people develop a new symptom or disease over a specified period of time. In contrast to incident, prevalence is a measure of the number of people in the population who have a symptom or disease at a particular point in time (Manchikanti, 2000). Therefore, it is necessary to note the methodological problems in the study of the epidemiology of LBP. Cunningham and Kelsey reported that back trouble is a frequent problem and the prevalence of back pain symptoms is estimated to be 17.2% from the data source of The United States (US) Health and Nutrition Examination Survey, 1971-1975 (HANES I) of the US adults aged 25-74 years (Cunningham & Kelsey, 1984). Strine and Hootman reported that from National Health Interview Survey in 2002 the prevalence of LBP increase with aging and the total prevalence of LBP only was 17.0% and the prevalence of both neck and LBP was 9.3% of US adults aged 18 years and over (Strine & Hootman, 2007
Prevalence of LBP in the general population