I agree it's potentially a useful hook to attract attention to a project, but as others have said, returning to work is the most challenging step for people who've regained some of their function. Unless you're fully recovered it's impossible to gauge how much work you could do until you try it (even when you're returning to a job you've done for years it's always harder than you thought!), let alone get a sense of whether a particular job will be sustainable.
But it is important, so maybe it could feature as one of the measures of improvement? Presumably, things such as taking a more active part in family life, resuming social activities and hobbies, and resuming or beginning a course of study will also be on the list. Outcomes like these could be presented as a scale with the most modest gains at the bottom and the most challenging at the top; it might help underline to potential funders that returning to work means climbing a ladder, not a doorstep. If a treatment helped and follow-up could be maintained for at least a year (two would be better), you might be able to show that some participants gained another rung or two during the period.
I don't know whether that's a useful approach, but it might be—policy makers know there's more to it than whether or not someone is working within a year. For someone who's been a long way from work returning almost always takes time, and even if they're not fit enough for work post-treatment, the ability to resume social activities or begin learning are still economic benefits. It can mean they're less likely to be dependent on services, and if they did eventually improve, they'd be in much better shape to move towards work.
If you're looking at it from the point of view of economic benefits to society as well as to the individual, people who're able to return to work may also:
- be contributing income tax;
- not be claiming social security;
- be saving for a pension, reducing their dependence on social security top-ups after retirement;
- be able to afford to buy a property or rent privately, reducing demand on social housing;
- have private or employer-provided health insurance and rely less on public healthcare;
- be able to look after their long-term health, reducing morbidity in later life;
- have more money available for discretionary spending in the economy.
I guess it depends on whose PoV you're looking at it from (societal or individual), the extent of the gains, and how well a chronically ill person is currently supported financially.
For some pwME, the individual financial impact is more likely to be negative rather than positive. Personal care is often the largest item on the budget, but if they weren't paying it in the first place, there's no saving. People who're able to do more after treatment are likely to grab the chance with both hands, and some of those things will cost money that they didn't need to spend when they were stuck in the house 24/7.
For someone who's been out of work a long time, returning to a job often has a negative financial impact for a year or more. Some of the issues:
- they may have no savings to set themselves up for work and little or no access to credit;
- their social security is stopped immediately, but they don't get a salary payment for at least four weeks;
- they have to find the money for a month's travel with no income to cover it;
- they might also have debt they need to service during this time;
- their wardrobe isn't geared up to working, and for some jobs they'll face a substantial outlay on clothes and shoes;
- for the first 12 to 24 months, these return-to-work costs, together with the normal additional costs of working, may mean they're worse off—or at least no better off—than when they weren't working.
(As you might be able to tell, I've been there, bought the t-shirt, grown out of it, and sold it as vintage on eBay.

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