BACKGROUND: While preliminary laboratory tests indicate that a hip belt reduces the load on the back, neck and shoulders associated with musculoskeletal strain, an orchard trial is needed to more realistically assess both effectiveness and acceptability. OBJECTIVE: to evaluate the hip belt's effectiveness in three areas: worker acceptance, worker productivity, and one-day muscle fatigue of the back and shoulder. METHODS:Ninety-six New York apple harvest workers were randomly assigned to use the intervention hip belt or placebo belt for one week. In a second week all workers switched conditions. Subjects were interviewed at the end of each week to ascertain intervention acceptance. Employer records were reviewed to determine bushels picked per day. Subjects also underwent muscle fatigue testing at the beginning and again at the end of one workday during each week. RESULTS: Ninety-one percent of the subjects favored the intervention hip belt. Use of the intervention did not appreciably slow picking speed (bushels per hour) as compared to placebo (8.8 bu/ hr vs. 8.89 bu/hr). Both were significantly faster than the regular equipment condition (8.13 bu/hr). No significant differences in one-day muscle fatigue were found with intervention use. CONCLUSIONS: The belt was acceptable to the workers and did not hinder productivity. However, the anticipated ergonomic benefits were not demonstrable using one-day strength testing.
RCT Entities:
BACKGROUND: While preliminary laboratory tests indicate that a hip belt reduces the load on the back, neck and shoulders associated with musculoskeletal strain, an orchard trial is needed to more realistically assess both effectiveness and acceptability. OBJECTIVE: to evaluate the hip belt's effectiveness in three areas: worker acceptance, worker productivity, and one-day muscle fatigue of the back and shoulder. METHODS: Ninety-six New York apple harvest workers were randomly assigned to use the intervention hip belt or placebo belt for one week. In a second week all workers switched conditions. Subjects were interviewed at the end of each week to ascertain intervention acceptance. Employer records were reviewed to determine bushels picked per day. Subjects also underwent muscle fatigue testing at the beginning and again at the end of one workday during each week. RESULTS: Ninety-one percent of the subjects favored the intervention hip belt. Use of the intervention did not appreciably slow picking speed (bushels per hour) as compared to placebo (8.8 bu/ hr vs. 8.89 bu/hr). Both were significantly faster than the regular equipment condition (8.13 bu/hr). No significant differences in one-day muscle fatigue were found with intervention use. CONCLUSIONS: The belt was acceptable to the workers and did not hinder productivity. However, the anticipated ergonomic benefits were not demonstrable using one-day strength testing.