Suppose you are searching for a car, and you’ve narrowed down your choices to a few models you can afford and looks good too(5 or 6). The most important criteria might be gas mileage, but when you compare the cars, the worst one in your selection gets 30 mpg while the best one gets 35. The difference here is not that grand. However, you may also care about size, and the smallest one in your selection may be a compact car while the biggest is a hybrid SUV. While gas mileage may be the most important criteria (you don’t want anything below 30mpg), you may prefer to drive a hybrid SUV that gets 30mpg versus a compact car that gets 35mpg. Thus, in this case size should be weighted more heavily than mpg. Swing weighting structures the weighting of the criteria to enable you to do this.

The above just deals with two criteria, but add a few more like price, resale value, horsepower, safety, etc and you can see how a complex problem becomes structured with the swing weighting technique

In the case you bring up, goal 1 is more important than goal 2, but we may not end up with treatment A, because someone might still be willing to give up progress toward their most important goal in order to make more progress on several less important goals. These kind of tradeoffs are harder to appreciate in my simplified example.

I haven’t yet discussed how one could go from a simple ranking of goals to a set of weights that would tell you how much more important one goal is than another, in part because that’s much harder for a patient to do and probably buys them a lot less than just getting their list of goals written out and putting an order to them.

Martin