Objective. This study aimed to evaluate the effect of reaction time, its derived variables IQ, postural sway (steadiness), safety courses, and age with respect to childhood agricultural injury (CAT) resulting from the chore of feeding animals by hand. We assume that shorter reaction time is associated with lower CAI risk, controlling for potential covariates.
Methods. The target population of this study was 4-H youth in the Central Ohio Area between 9 and 18 years old who were exposed to agricultural hazards. This thesis examined the subsets that were exposed to the possibility of injury while feeding an animal by hand (except pets). The larger cohort study was designed to be longitudinal. Data were collected during 1999-2001 in three stages: pre-baseline demographic information, baseline testing, and the daily diary (“Daily Record Books,” or DRB) which contains the amount of time spent on each agriculture-related chores over a period of 13 weeks. A model of the reaction time (Krieg, Chrislip, & Russo, 1996) was used to compute the following variables: the mean reaction time (MRT), the initial performance level (L1), the performance limit (L∞), the learning rate (l), and the fatigue rate (f). Gender difference in factors such as age and derived variables from the reaction time data were examined using t-test and chi-square test. Longitudinal analysis by using residual pseudo-likelihood was used to estimate the expected injury rate and risk factors.
Results. The results suggest that there are several differences in injury rate between boys and girls. The general safety course helped to prevent injuries in boys. The expected injury rate of those who had not taken the general safety course was 1.5 times higher than that of those who had taken the course in boys. Age and the fatigue rate of girls were an important factor in the expected injury rate. The expected injury rate of boys increased as the standard deviation of the reaction times decreased and as the week passed. For girls, the expected injury rates of the first two age groups were significantly different from that of the oldest group (p = 0.0003) and the second age group had the highest expected injury rate. The expected injury rate of girls increased as the fatigue rate increased and decreased as MRT increased.
Conclusion. We found that gender difference in injury rates and risk factors including age, safety class, and psychomotor skills are associated with farming related injuries in children and adolescents. Interestingly, we found that a lower MRT coincided with higher expected injury rate of girls, and the lower standard deviation of the reaction time coincided with higher expected injury rate for boys. More studies are warranted to determine whether high risk work environment is associated with lower reaction time.