The electronic database search yielded 756 published studies. After the removal of duplicates, 397 records remained for screening. Irrelevant titles (n = 262) were excluded, leaving (n = 135) for further examination by abstracts. After reading the abstracts, 27 potential studies were found eligible and their full-texts were printed. Finally, only 13 articles were included for data synthesis (Fig. 1).
Description of the studies
Various sources of data were reported in the included studies including the National Dutch Register ; Regie de’l Assurance Maladie du Quebec ; Skane Health Care Register ; Truven Health Market Scan Commercial Claims and Encounters ; National Hospital Discharge Register of Finland ; registration Network Groningen , US Defence Medical Epidemiology Database , the Intego Database , and the Emergency Department Information System  (Table 1). The included studies were conducted in Belgium , Canada [19, 26], Finland , the Netherlands [18, 22, 27], Sweden , USA [21, 24, 28, 29], and Israel . The sample size used to estimate the prevalence and incidence of LBP in the included studies ranged from 3900 to 7.5 million. The types of population included in the studies were industry workers (aerospace, defence industry, technology space and telecommunication), military personnel, self-reported patients, and adults living in USA, Quebec, and Sweden. All included studies scored ≥ 80% of risk of bias (low risk) for quality.
Five studies reported the prevalence rates of LBP (Table 2). The mean prevalence of LBP reported from the studies ranged from 1.4 to 15.6% [18, 20, 21, 24, 26]. The highest prevalence rates of LBP  were reported from workers in the aerospace and defence industry in the Unites States Benchmark Companies, whereas the lowest prevalence rates were reported from the residents of Quebec, Canada . The substantial differences within the two studies may explain that working in industry could be one of the major risk factors of LBP [19, 21]. Two studies have also reported that the prevalence rates of LBP in females were higher than males, which is contrary to the existing knowledge of LBP burden [20, 21].
The incidence rate of LBP was reported in ten studies [18, 21,22,23,24,25, 27,28,29,30]. The overall mean incidence of LBP reported from the nine studies ranged between 0.024 and 7.0%. The highest and lowest incidence of LBP was reported in the USA and the Netherlands, respectively [21, 27]. One of the explanatory factor for the difference in the incidence rate estimate may be the type of population considered in the studies. For example, people working in the aerospace and defence industry in USA were highly vulnerable than those working in the healthcare, mining and quarrying sector in the Netherland. Two studies reported that the incidence of LBP in female was higher than in male [21, 25]. Despite the difference in geographical locations where the studies were conducted, the incidence rates some studies have reported were approximately the same [22,23,24, 28] (Table 3).
There was virtually no agreement among researchers regarding the definition of LBP (Table 4). Some of the definitions of LBP included are 3digits ICD-9 and ICD-10 codes, lumbar and other intervertebral disc disorder with radiculopathy, LBP (M54.5), and dorsalgia (M54.5). The study by Bartholomeeusen et al.  and Spijker-Huiges et al.  also reported LBP symptom/complaint (LO3), back syndrome without radiating pain (L84), and back syndrome with radiating pain (L86) for LBP definition. The Dutch Classification for Occupational Health Care and Social Affairs has also defined a nonspecific LBP as acute (L101, M545), subacute (L102, M545) and chronic (L103, M545).Overall, various kinds of LBP are used in the included studies. The use of various kinds of LBP definition may lead to the wrong of use of LBP treatment.
Gender as a risk factor of LBP
As it is shown in Table 5, six studies reported data that could be used to investigate the potential risk factor of LBP using odds ratios. The odds ratios were calculated by dividing the odds of male by the odds of female in the selected studies. If the odds ratio is greater than one, then being male is considered to be associated with having LBP since being male increases the odds of LBP. Of those six studies, three studies reported that being male was associated with having LBP higher than female [18, 19, 23].