Baby Transportation Safety Statistics Is there a resource comparing different safety statistics for transporting babies on bicycles, specifically using different methods?

I'd like to see some information about how safe it is to compare a baby in a bike seat vs. in a trailer vs. in a box bike. Intuitively trailers seem to have the least risk of a fall, but might be more likely to be hit by an inattentive motorist. I've looked and I can't find any data about this.
I found this article - Tykes and Bikes - Injuries Associated With Bicycle-Towed Child Trailers and Bicycle-Mounted Child Seats

The paper estimates the numbers of trailer-related injuries and the number of child seat injuries:


  there were an estimated 322 injuries associated with the use of a bicycle-towed trailer (95% CI, 158-486) and an estimated 2015 injuries related to the use of a bicycle-mounted child seat (95% CI, 988-3042).


The paper notes that there is some uncertainty around these statistics:


  The data indicate the incidence of injury associated with the use of either bicycle accessory was low. However, injuries related to use of bicycle-towed child trailers were much less common (estimated 322 vs 2015). We do not know if this is because there are fewer bicycle-towed child trailers, resulting in lower exposure, or if there is truly a lower risk of injury associated with bicycle-towed child trailers.