Questioning the value of manual material handling training: a scoping and critical literature review

Manual material handling training (MMHT) is of questionable value according to five meta-analyses. However, little is known about why this is so. The aim of this study is to take a closer look at how MMHT are evaluated in order to identify what could explain judgement about their (lack of) effectiveness. Seventy-seven studies were included in a scoping review, and were analyzed using an inductive grid comprising numerous criteria. Workplace training programs, being the most frequent, were described in these papers in greater detail. Given the broad range of contexts it was found that MMHT differed greatly from one study to the other. All the while, contents presented through these programs were surprisingly uniform, with an emphasis on adopting the safe handling technique commonly known as "straight back, bent knees", although such training approach principally focuses on the trainee's behaviours, while paying little (to no) attention to the work conditions that might condition correct behavioral display. Limitations of current MMHT are discussed and explanations are given in order to better explain why they are reported to be so ineffective. Concrete recommendations on how to improve them close the paper.