a cost benefit basis? There is no benefit to the entity paying the money. It is a benefit to the recipients. A cost/benefit analysis is where the entity paying for the program derive some benefit from it. What benefit would the government get from paying the medical bills of old people? If you think about it, it actually increases costs to the government because it results in longer life expectancy which results in higher costs for the program
It would be cheaper if they just let everybody die if they could not afford medical care.

