Perhaps you should try some spelling variations:
significantly impaired » significantly impairs (Expand Search), significantly improved (Expand Search), significantly improve (Expand Search)
significant linear » significant clinical (Expand Search), significant gender (Expand Search), significant level (Expand Search)
impaired decrease » marked decrease (Expand Search)
linear decrease » linear increase (Expand Search)

You may be able to get more results by adjusting your search query.

• Removing quotes may allow a broader search: (( significant linear decrease ) OR ( significantly impaired decrease )).