学校因病缺课监测预警阈值的研究

Threshold value of early warning for infectious disease by school absenteeism surveillance in Shunyi District,Beijing

目的建立学校因病缺课预警阈值,为学校传染病疫情早期预警工作的开展提供科学依据。方法每日收集学校新增因病缺课人数,剔除多暴发疫情导致的缺课人数,计算常态情况下的班级和学校每日(周)因病缺课人均数(x-)和标准差(s),以均数加1～3倍标准差为备选预警阈值,通过实际缺课情况检验确定适宜预警阈值。结果学校日因病缺课人均数在1～3人之间,均数+3s为预警阈值时较适宜,其中中学为8人,小学为10人;学校周因病缺课人均数在6～11人之间,以均数+1s为预警阈值时较适宜,其中中学为16人,小学为18人;班级日因病缺课人数最大值均数在2～3人之间;以均数+1s为预警阈值时较适宜,其中中学为3人,小学为5人;班级周因病缺课人数最大值均数在3～4人之间;以均数+1s为预警阈值时较适宜,其中中学为6人,小学为7人。结论初步确立中小学日因病缺课预警阈值为8～10人,周预警阈值为16～18人;中小学班级日因病缺课预警阈值为3～5人,周预警阈值为6～7人。

Objective To establish a threshold value of early warning for infectious disease by school absenteeism surveillance to provide scientific evidence for early detection of outbreak of infectious disease at schools. Methods Data of daily absenteeism due to illness were collected from primary and secondary schools in Shunyi and number of absent students was recorded and estimated as daily and weekly mean number plus or minus standard deviation of the absent students （ x±s ）, excluding those absent due to disease outbreak, with mean plus one to three times of standard deviation as a selected warning threshold value and could be adjusted to an another adequate value abased on verification. Results As daily number of absent students averaged one to three per school, mean plus three times of standards deviation of the number of absent students was adequate for early warning, eight for secondary schools and 10 for primary schools, and as weekly number of absent students averaged six to 11, mean plus one standard deviation of the number of absent students was adequate, 16 for secondary schools and 18 for primary schools. As daily maximal number of absenteeism due to illness averaged two to three students per class, mean plus one standard deviation of the number of absent students was relatively adequate for early warning, three for secondary schools and five for primary schools, and as weekly maximal number of absenteeism due to illness averaged three to four students per class, mean plus one standard deviation of of the number of absent studefits was adequate for early warning, six for secondary schools and seven for primary schools. Conclusions Threshold value of early warning for infectious diseases was set-up preliminarily by school absenteeism due to illness, eight to ten daily and 16 to 18 students weekly per school for secondary and primary schools, and three to five students daily and six to seven students weekly per class.