"less impaired" is correct and usable in written English.
You can use it to describe something that is slightly, but not completely, impaired. For example, "The patient's vision was less impaired compared to the other patients."
In patients with impaired cardiac function, right ventricular performance is less impaired during NAVA titrated to the breathing pattern compared with PSV selected based on clinical criteria.
And those who do, studies show, are likely to be less impaired.
Honestly now, who wouldn't jump at the chance to have their prospects less impaired?
"And look, he's been less impaired by failure than some of the others, so that's given him a kind of lead role".
He's a good-looking, gifted, amusing man, less impaired than the French author with locked-in syndrome who wrote The Diving Bell and the Butterfly, but pretty immobile.
There are three classes in archery: ST for standing athletes, and W1 and 2 for those in wheelchairs, W2 being less impaired.
It has been noted that the fact that the acquisition of manual skill in Korsakoff patients is less impaired than either verbal learning or the solution of puzzles or mazes.
Although SSAD participants were less impaired than those with SAD, they were disadvantaged in many ways.
Adaptive immunity seemed to be less impaired by the shock than in adults.
In contrast, patients performance was less impaired on the Reasoning and Problem-solving and Social Cognition domains, differences that did not survive statistical correction for multiple testing.
On the contrary, MWA showed a clear habituation deficit at intermediate (0.3 and 0.2Hz) frequencies, only revealing a less impaired trigeminal nociceptive excitability during the interictal period.
