老人跌倒研究大部分著重在跌倒危險因子的探討，很少有跌倒機轉與傷害嚴重度相關研究，因此本研究探討傷害嚴重度與跌倒機轉及其他可能因子的相關性。方法：本研究對1200位社區老人追蹤18個月，期間共有145次跌倒發生，除了收集跌倒相關資料外，跌倒傷害嚴重度以簡易傷害量表（Abbreviated Injury Scale，簡稱AIS）分類為重傷(AIS≥2)、輕傷(AIS=1)及未受傷三個等級。多變項分析使用比例式勝算模式(Proportional odds model)分析與傷害嚴重度相關的因子。結果：跌倒中有27.3%為重傷，53.9%為輕傷及18.9%爲未受傷。多變項結果顯示女性的傷害較男性嚴重（勝算比為3.36）；屋外較屋內的跌倒嚴重（勝算比爲2.08）；身體重心垂直移動（勝算比爲3.63）及水平移動（勝算比為3.31）的跌倒較身體重心不變時的傷害嚴重；前跌（勝算比為2.83）與側跌（勝算比為3.67）較後跌的傷害嚴重；跌倒先著地在肩部以上較先著地在臀部的傷害嚴重（勝算比爲3.98）。另外跌倒機轉中，跌倒前身體重心移動、跌倒方向及最先著地部位三個動作的共同分布有關聯性。結論：本研究結果有助於老人跌倒時發生傷害的瞭解，並可進一步發展避免嚴重傷害的預防方法。

Purpose: This study was to determine the relations between fall mechanism, as well as other factors, and injury severity among fallers from a cohort of 1200 community-dwelling persons aged 65 and older. Methods: During an 18-month follow-up period, 145 falls were ascertained. When a fall was reported by an elderly or ascertained from telephone interviews at 3-month interval or from medical records of local clinics, fall-related information on injury patterns, fall mechanism, and other characteristics was collected by home visits. The proportional odds model was used to determine factors associated with injury severity, with three levels, i.e., severe (Abbreviated Injury Scale, AIS≥2), mild (AIS=1), and non- injuries. Results: Of these falls, 27.3% had severe injuries, 53.9% had mild injuries, and 18.9% non-injuries. The adjusted odds ratio (OR) of female to male for having a greater level of injury was 3.36 with 95% confidence intervals (CI) of 1.58 to 7.16. Compared with indoor falls, outdoor falls had greater level of injury (OR=2.08 with 95% CI of 0.99 to 4.37). Before a fall occurred, the vertical (OR=3.63 with 95% CI of 1.23 to 10.8) and horizontal displacement (OR=3.31 with 95% CI of 1.23 to 8.89) of body's center-of-gravity had greater level of injury compared to no or slight changes of center of gravity. Forward (OR=2.83 with 95% CI of 0.87 to 9.27) and sideways (OR=3.67 with 95% CI of 1.09 to 12.3) falls had greater level of injury compared to backward ones. Impact at body regions above shoulder also had an increased odds of greater injury severity compared to impact at buttocks. Conclusion: The identified factors associated with injury severity may provide the information on reduction of severe falls injuries among older people.