Farmers are at high risk of having low back disorders (LBDs). Agriculture employs half the global workforce, but it is unclear whether all farming populations are represented equitably in the LBD literature. This systematic review quantifies the number and quality of research studies by geographical region, agricultural commodity, and farmer characteristics. MEDLINE, Web of Science, CINAHL, Scopus, and Embase databases were searched using conceptual groups of search terms: "farming" and "LBD." Screening and extraction were performed by two researchers in parallel, then reconciled through discussion. Extracted study characteristics included location of study; commodity produced; worker sex, ethnicity, and migration status; type of employment; and study quality. These were compared with agricultural employment statistics from the International Labour Organization and World Bank. From 125 articles, roughly half (67) did not specify the employment context of the participants in terms of migration status or subsistence versus commercial farming. Although in many regions worldwide women make up the bulk of the workforce, only a minority of low back disorder studies focus on women. Despite the predominance of the agricultural workforce in developing nations, 91% of included studies were conducted in developed nations. There was no significant difference in study quality by geographic region. The nature of the world's agricultural workforce is poorly represented by the literature when it comes to LBD research. If developing nations, female sex, and migrant work are related to increased vulnerability, then these groups need more representation to achieve equitable occupational health study.
Keywords: Agricultural workers; farmers; global health; low back disorders; musculoskeletal disorders; systematic review.