To examine occupational injury rates in a dual-response emergency medical services (EMS) system before and after implementation of a power-lift stretcher system.

中文翻译：

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城市急救医疗服务系统中动力担架对工伤发生率的影响

旨在检查双响应紧急医疗服务 (EMS) 系统在实施动力升降担架系统之前和之后的职业伤害率。