First things first - 85% of the fractures you're talking about are arm and leg fractures. Skull fractures, which was what I was talking about, are a significantly smaller number.
But yes, we should investigate why the child broke their arm. Does that need to be an in-depth investigation? Not usually. But it's important to understand why these things happen; that's where the data for the study you cited comes from.
But yes, we should investigate why the child broke their arm. Does that need to be an in-depth investigation? Not usually. But it's important to understand why these things happen; that's where the data for the study you cited comes from.