**2. Materials and Methods**

To search for information about the different RULA method applications, the University of Almería's library website was accessed. There, we used the "Web of Science" (WoS) database, the license of which is managed by the Spanish Foundation for Science and Technology (FECYT).

The search was done by selecting the "Web of Science Core Collection" and the advanced search option, in which "so = Applied Ergonomics" was introduced. The "Create Citation Reports" option was selected. In this way, the total number of available citations was consulted for the original article proposing the RULA method by McAtamney and Corlett [20].

The number of studies obtained was 809, in the period from 1993 to 29 April 2019. Of these, using the title and abstract of each study, we finally selected a total of 226 results, discarding those that did not include the method's application. The final studies were from 1998 to 2019.

It should be noted that the main limitation of the information search is that we only used the Web of Science Core Collection; no other databases were accessed. Therefore, some studies may have been overlooked with the search method used.
