Study Selection
About 1114 articles, editorials, and reports were searched through electronic databases such as Web of Science, SCOPUS, PubMed, Google Scholar, CINAHL, Cochrane Library, African Index Medicus, African Journals Online databases, and Science directly from 10 September to 12 October 2020. Following the search for articles, 285 duplicate articles were excluded. Furthermore, 706 articles were excluded after initial selection, and 35 articles were excluded after full-text articles were assessed for eligibility, of which 20 articles were included in the systematic review and meta-analysis (Figure 1).
Characteristics of Included Articles
In this study, a total of 9,410 participants were included in 20 articles conducted in Ethiopia and published from 2017 to 2020 [29-48]: 9 (45.0%) articles [30,32,38,39,41,43,44,47,48] conducted in Oromia, three (15%) in Tigray [31,36,45], three (15%) in SNNP [29,34,35], three (15%) articles in Addis Ababa [33,40,46], two (10%) articles in the Amhara region state. All included studies were cross-sectional studies with a sample size ranging from 264 [45] to 771 [40] study participants.
Among the included articles, 10(50%) [30,33,34,36,37,39,40,42,43,47] of the included articles reported the prevalence of both low back pain and upper back pain, 9(45%) articles [29,31,32,35,41,44-46,48] reported the prevalence of low back pain alone and 1(5%) [38] reported the prevalence of upper back pain alone.
Furthermore, 8 (40%) included articles were published in 2020 [29,31,32,34,44-47], followed by studies published in 2019[36-38, 41-43] that represented 6 (30%) of the included articles. According to the JBI Critical Assessment tool [25], all included articles had a low risk of bias. The occupational-related prevalence of low and upper back pain in the previous year ranged from 25.5% [41] to 74.8% [36] and 10.4% [29] to 60.4% [35], respectively (Table 1).
Prevalence of Occupational-Related Upper and Low Back Pain
The meta-analysis was performed using the Comprehensive Meta-Analysis (CMA) Version 3 statistical package (software) to determine the combined prevalence of occupationally related low back and upper back musculoskeletal disorders in Ethiopia.
Prevalence of Occupational-Related Upper Back Pain
The pooled prevalence of occupational-related upper back pain in the previous year was 27.1% with a 95% CI of 18.4 to 37.9% (Figure 2). After a subgroup analysis was performed based on occupation, the overall pooled prevalence of occupational-related upper back pain in the previous year was 34.7% (95% CI: 33.1, 36.2%). The lowest prevalence [10.4% (95% CI 7.6, 14.1%)] was reported among vehicle repair workers, while the highest prevalence [60.4% (95% CI 55.7, 65.0%)] was reported among women loading pedestrians (Supplementary file I; Figure 1).
After the subgroup analysis was performed based on the publication year, the overall pooled prevalence of occupational-related upper back pain in the previous year was 43.8 % [95% CI 39.9, 47.7%)]. The lowest prevalence [15.3% (95% CI: 11.7%, 19.8%)] was reported in the study published in 2018 while the highest prevalence [60.4% (95% CI: 55.7, 65.0%)] was observed among the study published in 2017 (Supplementary file I; Figure 2).
Furthermore, based on the study region, the total pooled prevalence of occupational-related upper back pain was 36.2 % with 95% CI: 33.6, 39.0%)]. The lowest pooled prevalence [22.1% (95% CI: 9.2%, 44.5%)] was reported among the studies conducted in the Oromia regional state, while the highest prevalence [38.8% (95% CI: 34.2, 43.6%)] was reported by the study conducted in the Amhara regional state (Supplementary file I; Figure 3).
Prevalence of Occupational-Related Low Back Pain
The pooled prevalence of occupational-related low back pain in the previous year was 54.2% with a 95% CI of 48.2, 60.0 (Figure 3). Based on the subgroup analysis of the prevalence based on occupation, the overall pooled prevalence of occupational-related low back pain in the previous year was 52.8% (95% CI 51.3, 54.3%). The lowest prevalence [25.5% (95% CI: 21.5, 29.9%)] was reported among construction workers, while the highest prevalence [67.3% (95% CI: 62.7, 71.6%) with a p-value <0.001] was reported among women loading pedestrians (Supplementary File I; Figure 4).
After subgroup analysis was performed based on the publication year, the overall pooled prevalence of occupational-related low back pain was 61.8 % (95% CI: 58.9, 64.6%). The lowest pooled prevalence [46.9% (95% CI: 39.9%, 54.0%)] was reported among studies published in 2020, while the highest pooled prevalence [65.7%, (95% CI: 62.5, 68.9%)] was observed among studies published in 2017 (Supplementary file I; Figure 5).
Furthermore, after the subgroup analysis was performed by study region, the overall pooled prevalence of low back pain was 55.2 % (95% CI: 51.4, 59.0%). The lowest pooled prevalence [50.7% (95% CI: 25.0, 76.0%)] was reported among studies conducted in the Tigray regional state, while the highest prevalence [56.3% (95% CI: 37.1, 73.9%)] was reported among studies conducted in Southern Nations, Nationalities, and Peoples (Supplementary File I; Figure 6).