The phrase "about how significantly" is correct and usable in written English.
It can be used when discussing the extent or degree of something, often in a context that involves analysis or evaluation.
Example: "The report provides insights about how significantly the new policy has impacted employee productivity."
Alternatives: "regarding the extent to which" or "concerning the degree of".
Last year, I wrote about how Google significantly improved spell-checkers by using massive databases of users' self-corrections to do work that previously required hand-crafted algorithms focussed on the intricacies of English spelling and the psychology of typing.
How significantly has that role changed?
How about 11? How about nine?
But a small related conference the day before, held at a hotel one mile north, revealed significantly more about how the movement plans to overturn the 1973 Roe v. Wade decision and eliminate abortion across the country.
On the fourth episode of "Sustainable Self," a HuffPost Originals series about how your everyday choices can significantly affect the earth, we discuss the simple changes you can (and should) make to lessen your pet's impact on the planet.
The reaction to the news that UK car production has dropped significantly says much about how we measure economic success.
All sides in the current debate -- from Mr. Powell and Mr. Martin to Mr. Copps -- say they agree with the goals but then reach significantly different conclusions about how to achieve them.
I was 19, and knew almost nothing about anything — certainly not about real work, and not about how work almost always affiliates you significantly with the lives of others.
"One of the things that really affected me was listening to everybody's very sad story about how they had had their lives significantly changed and were feeling very much that they had lost control of the situation," says Chalmers.
Significantly – given concerns about how Charles might square his campaigning and sometimes controversial lobbying of government ministers with being the head of state – the article concludes that "far from itching to assume the crown, he is already feeling its weight and worrying about its impact on the job he has long been doing".
