Globally various studies have reflected burden of leg ulcer in terms of prevalence, incidence rate, morbidity, and mortality associated with leg ulcer and health cost involved in its management. Chronic leg ulcers affect 0.6–3 % of population aged over 60 year and increasing to more than 5 % of those aged 80 years and above. Rayner et al. (2009) have stated that chronic leg ulcer disease is an important cause of morbidity with prevalence in the community ranging from 1.9 to 13.1 % [7]. Sasanka et al. (2012) have stated in their study that in the course of a lifetime, nearly 10 % of the population will develop a chronic wound, with a wound-related mortality rate of 2.5 % [6].

According to Cheng et al. (2011) about 15 % of elderly adults in the United States suffer from chronic wounds and in chronic leg ulcer disease predominantly venous stasis ulcers, pressure ulcers (bedsores), and diabetic (neuropathic) foot ulcers. In America yearly 2–3 million new cases are diagnosed with various types of chronic wounds [8]. The prevalence of vascular ulcer in the United States is estimated at 500,000–600,000 and increases with age. Estimated annual incidences of leg ulcer in Switzerland and the United Kingdom are 0.2 and 3.5 per 1000 individuals, respectively [9, 10].

Faria et al.’s (2011) study in Botucatu, Sao Paulo, Brazil, reported a 35.5 % prevalence of varicose veins and 1.5 % prevalence of severe chronic venous insufficiency with an ulcer or an ulcer scar [11]. The peripheral artery disease commonly associated with non-healing wounds affects about 8 million Americans and 12–20 % of Americans of age group 65–72 years. An estimated over 7.4 million population suffer from pressure ulcers around the world where estimation was possible. This estimate is not including a major number of developing countries [12].

In Western Australia, 1994, leg ulcers were found to affect nearly 1.1 per 1000 population (0.11 % point prevalence). The study of Baker et al. (1994) demonstrated that 24 % of the population suffered from ulcers for 1 year, 35 % had a problem of ulceration for 5 years, 20 % had experienced 10 or more episodes of ulceration, and 45 % of the sufferers were housebound [13]. Jull et al. (2009) stated that although the period prevalence of leg ulcers in New Zealand was at 79 per 100,000 per year, capture analysis suggested a more accurate estimation, which was between 393 and 839 per 100,000 per year [14].

According to data from epidemiological studies, the incidence of chronic ulcers in surgically hospitalized patients in China is 1.5–20.3 %. In one study of the 580 wound areas in 489 patients, 366 or 63 % were ulcers on the lower extremities [15, 16]. Korber et al. (2011) stated in their study conducted in Germany that venous insufficiency was the predominant causative factor in 47.6 % and arterial insufficiency in 14.5 % and 17.6 % of ulcers were due to combined arterial and venous insufficiency [17].

Ruckley (1997) has stated that chronic venous insufficiency affects approximately 5 % and chronic leg ulcer approximately 1 % of the adult population of developed countries. Recent quality-of-life studies highlight major disability and social impairment associated with chronic leg ulcer disease, but they also reflect that this condition is characterized by chronicity and relapse and hence giving rise to massive healthcare expenditure. This expenditure was accounted in the United Kingdom to be around E400 million per annum. Venous diseases are consuming 1–2 % of the healthcare budgets of European countries. In France too, the costs of venous disease represented 2.6 % of the total healthcare budget in 1995, thus confirming other data from European studies and an early health survey in the United States [19–21].

Similarly in the United States, treatment costs for venous ulcers in more than 6 million patients approached $2.5bn (£1.6bn; €1.8bn), and 2 million workdays were lost annually because of venous ulcer disease [22, 23]. A recent prospective study performed in 23 specialized wound centers throughout Germany calculated the mean total cost of a venous ulcer per patient per year to be €9569 (€8658 (92 %) direct costs and €911 (8 %) indirect costs [23, 24].

Epidemiological studies are used to assess the prevalence of diseases or conditions within populations in order to ascertain the magnitude of a certain problem. Mostly cross-sectional studies have been used to assess the number of patients with a certain disease within the healthcare system. Large randomized samples have been used to assess populations, and such samples have the advantage of knowing people who are suffering from chronic leg ulcer disease but are self-treating and are out of reach to the healthcare system.

Prevalence data from such studies will serve as a valuable basis for the planning of appropriate actions to deal with the problem. Impact and effectiveness of current treatment modalities can be assessed by doing repeated prevalence based studies in a defined geographical region and subsequently these studies can suggest for need of improvements in current treatment strategies [25–32]. For example, in an observation of Skaraborg, the prevalence of leg ulcer decreased by 46 % within the healthcare system from first epidemiological studies (1988–1992) compared to a repeat study in 2002, giving a strong indication that our changed management strategy was successful. In the absence of repetitive planned prevalent studies, it would have been much more difficult to detect the result of this change of management strategy [26–32].

For a prevalence data to be reliable, the study has to be large enough. Validation of all or a randomly selected sample of the reported patients is mandatory to determine the number of false positives (described later) and to establish the diagnosis. It is not appropriate to rely on a venous ulcer diagnosis by the healthcare giver without verification from a previous objective noninvasive assessment. Without objective validation there is a high risk of overestimating venous leg ulcer prevalence [32].