Injury Prevention Research Unit, Dept of Preventive and Social Medicine, Dunedin School of Medicine, University of Otago, PO Box 56, Dunedin 9054, New Zealand.
Inj Prev. 2013 Jun;19(3):153-7. doi: 10.1136/injuryprev-2012-040345. Epub 2012 Jun 30.
(1) Estimate age, period and cohort effects for motorcyclist traffic casualties 1979-2008 in New Zealand and (2) forecast the incidence of New Zealand motorcycle traffic casualties for the period 2019-2023 assuming future age, cohort and period effects, and compare these with an estimate based on simple linear extrapolation.
Age-period-cohort (APC) modelling was used to estimate the individual effects of age, period and cohort after adjusting for the other two factors. Forecasting was produced for three period-effect scenarios.
After adjusting for cohort and period effects, 15-19-year-olds have substantially elevated risk. The period effect reduced in significance over time until the last period, 2004-2008, where the risk was higher than the preceding period. The 10-year cohorts born 1949-1958, 1954-1963, 1959-1968 and 1964-1973, had elevated risk. The forecasting, based on APC modelling, resulted in the lowest estimates of the future incidence being approximately one-third that of the highest estimate (6641).
Trends in motorcycle casualties have been influenced by significant independent age, period and cohort effects. These need to be considered in forecasting future casualties. The selection of the period effect has a significant impact on the estimates. Which period-effect scenario readers choose to accept depends on their views about a wide range of factors which might influence motorcycle use and crash risk over time.
（1）估计 1979-2008 年新西兰摩托车事故伤亡的年龄、时期和队列效应；（2）假设未来的年龄、队列和时期效应，预测 2019-2023 年新西兰摩托车交通事故的发生率，并将其与基于简单线性外推的估计进行比较。
使用年龄-时期-队列（APC）模型，在调整其他两个因素后，估计年龄、时期和队列的个体效应。为三种时期效应情景进行了预测。
在调整了队列和时期效应后，15-19 岁的人风险显著升高。时期效应随着时间的推移逐渐减弱，直到最后一个时期，即 2004-2008 年，风险高于前一个时期。1949-1958 年、1954-1963 年、1959-1968 年和 1964-1973 年出生的 10 年队列风险升高。基于 APC 模型的预测结果导致未来发生率的最低估计值约为最高估计值（6641）的三分之一。
摩托车事故的趋势受到显著的独立年龄、时期和队列效应的影响。在预测未来伤亡情况时需要考虑这些因素。时期效应的选择对估计值有重大影响。读者选择接受哪个时期效应情景取决于他们对可能随时间影响摩托车使用和碰撞风险的各种因素的看法。
