Table 1

Six-point avoidability scale

RatingCategoryDescription
1Totally unavoidableVirtually no evidence of avoidability
2UnavoidableSlight to modest evidence of avoidability
3Possibly avoidablePossibly avoidable, <50–50, but close call
4Probably avoidableProbably avoidable, more than 50–50, but close call
5Probably avoidableStrong evidence of avoidability
6Totally avoidableVirtually certain evidence of avoidability