Does “jury is still out” mean "the conclusion is still not made/decided"?

Context:

Some Americans try to make up for their bad eating habits by taking multivitamins and supplements like fish oil. Manson said everyone needs vitamin D, and the recommended adult guideline is 800 IUs (international units) with calcium for bone health. But the jury is still out on whether greater amounts might prevent cancer and cardiovascular disease. Testing is being done on doses of 2,000 IUs daily, she added. Still, Manson said the “jury is still out” as to whether many supplements are safe and effective.