Short- vs. long-term makes a difference.

Short-term disability, also known as sick leave, starts as soon as you're unable to work due to illness, injury or the birth of a child. Forty-seven percent of U.S. employers offer short-term coverage and 40% provide long-term disability, according to industry trade group LIMRA. Some states, such as New York and California, require a minimum level of short-term benefits. You can read buying tips and ways to compare policies here and here.