The league has researched various ways to bring basketball back safely, sources say, including the use of a sampling procedure called “group testing,” which aims to examine a large number of people with just a few tests. The league is also contributing to a nationwide antibody study at Mayo Clinic that involves an innovative new fingerstick test kit. Based on my conversations with sources at the league office, team executives, and medical professionals, here’s what the NBA is working on now, and what the testing process might look like if games were to resume.