Selecting and piloting assessment methods

The selection of assessment methods for the task assessments on plants was a

compromise between what would yield the most useful data on MSD, what would be practical in the challenging work environment, and what would be acceptable to those involved. Most importantly, the assessment of the high MSD-risk tasks needed to encompass all elements of the work system within which they occurred for identifying the presence of physical, psychosocial, organisational and other contextual factors. There is support from the literature for such an approach in the quest for addressing MSD with a range of interventions aimed at addressing this broad scope of risk factors (NRC-IOM, 2001; Silverstein & Clark, 2004; Buckle, 2005; Marras et al., 2009).

Prior knowledge of the meat processing work environments gave some insight into what methods would be appropriate to use on the plants. The most significant restriction was that of time, as the processing line continues relentlessly and trained replacement staff that enable participants to step off-line are often limited. A further constraint was the effect of high noise levels, and accompanying hearing protection, both limiting conversation and privacy, particularly in situations where participants are unable to leave the processing line. Limited space available for observing and recording data or interviewing staff (without getting in the way or risking accidental injury from other staff, machinery or carcasses) can also impact negatively on privacy and therefore on data quality as well. Hygiene compliance requirements can also affect what data are collected. Most plants do not allow any equipment into the processing areas for fear of product contamination; reflected in the fact that the protective clothing provided often has no pockets. For the same reason, task participation opportunities are minimal. Protective clothing worn in the processing areas serve as barriers against injury and zoonotic disease, but also verbal communication (ear plugs, face and beard masks). Hygiene standards can also affect the location and length of the semi-structured

interviews as people in most tasks are unable to move out of the work area without first undergoing a decontamination and washing process.

Task analyses of the high MSD-risk tasks were considered, but not conducted due to variations in the high MSD-risk tasks between plants. Task descriptions were developed instead which included the most common task variations (section 4.3.2).

Acceptability of assessment methods by the MIHSF and other industry stakeholders centred around four requirements. Firstly, that our presence did not adversely affect productivity on the processing line or personal earnings in the case of piece rate payment. Secondly, that confidentiality of both of the plant and the participants was maintained. Thirdly, that hygiene compliance requirements were not compromised, and finally, that our involvement did not set unrealistic expectations for the participants or the plants.

The combination of all these factors resulted in several iterations of site schedules and data collection forms. Deciding on the site schedules was more straightforward given the finite resources available and the known locations of the plants. Importantly, the methods needed to be achievable by one researcher. Once the researcher was at the plant, the amount of time required to collect the data was less of an issue than being able to collect it single-handedly. A structured interview schedule was initially considered for the interviews, as this would enable easier comparison of the responses. However this was changed in favour of a semi-structured interview format due to: the complexity of the information involved, the predicted levels of emotion attached to MSD, and the wide range of views on the topic (Sinclair, 2005). Additionally, a less formal interview process would be consistent with the manner and expectations of most participants and would better match the environmental conditions in which they were to take place (wet, contaminants, restricted space, high noise levels). Using interviews also removed the barrier of literacy, an issue raised by some industry stakeholders and known to be a significant issue in many companies. For the same reasons approval was sought and gained from the ethics committee to reduce the information sheet from two pages down to one page in length (Appendix 2).

Simple forms were used for collecting archival and establishment data from each plant, as well as recording raw events and task cycle times during periods of observation. Established postural analysis tools were also available when required. These data sources were collected to help triangulate findings from the semi-structured interviews. Initial intentions to collect photos and video footage were abandoned due to plant concerns over confidentiality and hygiene. As outlined by David (2005), the methods chosen provided the best match between the requirements of the study, the preferences of the host plants and the finite resources of the study.

Members of the research team along with two members of the MIHSF evaluated draft assessment forms and interview schedules. Once changes were made, the forms and the assessment process were piloted at three meat processing plants. The three plants were selected based on the support of the plant health and safety staff and geographical convenience. The pilot process included evaluation of the forms, the order and timing of events on site and the collation of the data collected. Minor changes were made to the forms and the data collection process to make the most efficient use of the time on plant as well as time spent collating and analysing data. A checklist was developed for organising plant visits and ensuring a consistent process was applied (Appendix 4). As part of the ethical approval process, information sheets and consent forms were

available for all plant staff involved in the assessment process (Appendix 1). A total of 250 hours of on-site analysis was undertaken across the study sample. Additional visits were made to a further six processing plants prior to and during the early stages of the task assessments to increase understanding of the industry, and to discuss and test assessment methods.