Number of children dying or last seen (censored) during each year of follow-up.

*All children in the cohort were aged 12 years or older at the time of ascertainment of deaths in 2007, thus losses from follow-up at younger ages were due to death or censoring alive on the date last seen (as recorded in hospital case notes). Between 12 and 15 years there are fewer children under follow-up (‘at risk’) in the older age groups as many children had not reached these ages and this reduced the precision of survival estimates after 12 years.Number of children dying or last seen (censored) during each year of follow-up.

* 本研究队列（cohort）中的所有儿童在2007年开展死亡确认时均已年满12周岁，因此较年幼年龄段的随访失访均归因于死亡，或是于末次随访当日仍存活时的截尾（censoring），相关信息均记录于医院病历中。在12至15岁年龄段内，高龄组的随访儿童（即风险人群（at risk））数量更少，这是由于多数儿童尚未达到该年龄段，进而导致12岁之后的生存估计精度有所下降。本数据集统计了各随访年度内死亡或末次随访（截尾）的儿童人数。