Risk Factors Of Injuries Among Adolescents And Young Students:a Prospective Cohort Study

Objective To describe the epidemiological features and determine related risk factors of injuries among adolescents and young students in Ma anshan City of Anhui province.Methods A prospective study on injuries for 1-year period was carried out among 1 494 middle,high and college students who were selected from 1 junior high school,1 senior high school and 1 college in Ma'anshan city from January 1,2008 to December 31,2008. Information on injury events were collected by teachers,school doctor or class health worker. During vacation,students reported injury events by themselves and they that were checked by teachers or school doctor or class health workers after back to school.The injury events rate were calculated according to each factor,and injury time,place,position,severity,medical treatment and disability.Before follow-up,depression and anxiety were described by Self-rating Depression Scale and Self-rating Anxiety Scale among statuas. According to percentile 25,50 and 75。Depression and anxiety statuas were divided into four levels:low quartile (P50,≤P75) and upper quartile (>P75). At the same time, students were assessed by sociodemographic factors,characteristics of personality and behaviors from students'self-reported. Univariate analysis was performed using the chi-square test to determine correlation between repeated injury rate and variables. Multinomial logistic regression models were adopted to evaluate main factors associated with injury rate. Results A total of 1 639 injury events occurred among 799 students,with an incidence rate of 53.48%. Repeated injury rate was 13.39%,consisted of 200 students who suffered 854 injuries,with an incidence rate of 52.10% among total injuries. There was statistically significant difference in injury rate of different times according to boys'education level (χ2= 17.181,P=0.009) but there was no difference by girls'education level (χ2= 5.505,P=0.481). Leading two injuries were abrasions and falls at all education levels (junior high school:35.78%,28.96%;senior high school:39.50%,22.10%;college:35.67%,18.94%). The cumulative incidence rate of college students was the highest at different education level among 14 kinds common injuries. More injury occurred in July and August,and the most vulnerable time to injury of the day was 3 pm～5 pm,then around 12 at noon. Home and campus of injury were common places,fingers and toes were the most vulnerable areas for injury. Most of the injuries were unexpected and usually mild. Most injury events were simply dealed with by themselves. The rate of absence from school due to injury events was 4.58%. Chi- square test indicated that rate of activity limitation increased due to injury events with the increasing of education level (χ2=61.487,P=0.000) and so was the rate of lying due to injury in college students was the highest(χ2=36.520,P=0.000).Our results revealed that there was no statistically significant difference in the rate of one, two and repeated injury with the increasing of depression levels and anxiety levels (P>0.05). Trend chi- square test showed that repeated injury rate reduced with the decreasing of anxiety levels (P<0.05). Among four levels of self-rating depression in boys,repeated injury rate of upper quartile was higher than other levels (P<0.05);and among four levels of self-rating depression in girls,the difference of repeated injury rate was not statistically significant (P>0.05). Among four levels of self-rating anxiety in girls,repeated injury rate of upper quartile was higher than other levels (P<0.05);and among four levels of self-rating anxiety in boys,difference of repeated injury rate was no statistically significant (P>0.05). Chi- square test revealed that there was statistically significant difference in the incidence rate of one injury among three levels of self-evaluated family atmosphere (P<0.05). There was statistically significant difference in the incidence rate of twice injury among three levels of self-evaluated temperament(P<0.05). There were statistically significant difference in the incidence rate of repeated injury among gender,education levels,living environmen,education level of mother,education level of father,population in a family and economic level of family (P<0.05).Multinomial logistic regression analysis showed that male,4 or over people in a family, extraversion,self-assessed normal figure type and upper quartile of self-rating anxiety symptoms were the risk factor of repeated injuries. Perceived moderate or above family economic level,mothers with senior high school education,harmonious atmosphere in the family and upper quartile of self-rating depression symptoms were protective factors of repeated injuries.Conclusion Injury rate was high in junior high school,senior high school and college. Injury rate varied by different sex , ages , locations and seasons. Sociodemographic factors and emotional status may predict repeated injuries which should be worth of further research.