Embodiments of the invention include a vehicle telematics system including a telematics device and a remote server system, wherein the telematics device obtains sensor data from at least one sensor installed in a vehicle, calculates peak resultant data based on the sensor data, generates crash score data based on the peak resultant data and a set of crash curve data for the vehicle, and provides the obtained sensor data when the crash score data exceeds a crash threshold to the remote server system and the remote server system obtains vehicle sensor data and vehicle identification data from the vehicle telematics device, calculates resultant change data and absolute speed change data based on the obtained sensor data and/or the vehicle identification data, and generates crash occurred data when the resultant change data exceeds a first threshold value and when the absolute speed change data is below a second threshold value.