The study looked at how accurately and precisely different data collection methods can estimate exposure variability in occupational posture recordings. They analyzed minute-by-minute arm elevation data from car mechanics to simulate various sampling strategies. The researchers found that sampling in small blocks within days gave unbiased results, but larger block sizes led to bias in variance component estimates. Increasing the number of days for sampling improved precision but sometimes reduced accuracy. Overall, accurate and precise estimation of exposure variability requires larger samples of data than estimating average exposure levels.