OK, I understand now. I think that there is a huge difference between:
1) Spending 4 person-hours on activity X will change the outside world to produce Y QALYs.
2) Spending 4 person-hours on activity X will lead you to spend 40 person-hours to produce Y QALYs
If I don’t think Y QALYs/40 hours is cost-effective enough to want to pursue, then I don’t want to do 2), even if Y/4 hours would be enough.
OK, I understand now. I think that there is a huge difference between:
1) Spending 4 person-hours on activity X will change the outside world to produce Y QALYs.
2) Spending 4 person-hours on activity X will lead you to spend 40 person-hours to produce Y QALYs
If I don’t think Y QALYs/40 hours is cost-effective enough to want to pursue, then I don’t want to do 2), even if Y/4 hours would be enough.