"I'm quite afraid (and virtually certain) we will never have any good news about Michael," Gary Hartstein, a former F1 doctor, said.
"At this point, I rather dread seeing that the family has put out a press release."
"I can conceive of no possible reason that Michael's entourage, understandably extremely protective of his and their privacy, would not tell his fans if significantly good things have happened,” he added in a post on his blog.
"Slowly, everybody is really worried," Roger Benoit, F1 commentator, recently added. "Slowly, everybody is really worried. Grenoble and the family have been silent for weeks. Why?"
Career in Pictures: Michael Schumacher
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Doctors began the gradual process of bringing Schumacher out of his coma 18 weeks ago.
"There are short moments of consciousness and he is showing small signs of progress," Kehm told German broadcaster ARD.
"There are moments when he is awake and moments when he is conscious.
"Of course I am not a doctor, but medically, there is a distinction between being awake and being conscious, the latter meaning there is an ability to interact with his surroundings.
"I don't want to disclose details out of respect for the family, but we have no doubt at all in the abilities of the doctors treating Michael, they are experts in their field."
Despite the positive report, Kehm also stressed that any medical prognosis is "not possible" due to the severity of the brain injury Schumacher sustained, and that any interaction with the former driver is "on a very limited basis".
Kehm has been particularly careful with her statements not to give any more information than what the doctors have passed on, although she has also had to address rumours that have circulated since the accident.
"What upsets the family most is media quoting doctors who are not treating Michael and untruths are constructed from these," added Kehm.
"It has been a problem when outsiders comment and it means we have to set the record straight, even when we don't want to."
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