I must admit I don't have any comprehensive stats to hand, even the WHO have only recently compiled worldwide occurrence stats but not correlation / causation stats.

However from a programming paradigm, which would you prefer? Bugs cleaned up only because "someone" reported them, or because you use CI and can fix the problem at source, can measure testing coverage, etc, etc. I think most programmers agree that the proactive systemic testing system is better than ad hoc.