Perhaps you should try some spelling variations:
significantly impaired » significantly improved (Expand Search), significantly improve (Expand Search), significantly improves (Expand Search)
significantly mean » significantly less (Expand Search), significantly mediate (Expand Search), significantly impact (Expand Search)
impaired decrease » marked decrease (Expand Search)
mean decrease » a decrease (Expand Search)

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

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