Each NLST project may now receive CT images from up to 15,000 participants (of the investigator’s choice).

Investigators are encouraged to consider taking fewer than 15,000, because:

1. Many applications do not need that many.
2. The maximum total data size for 15,000 people is very high (8 terabytes).
3. The number of available screen-detected lung cancer cases (~600) and benign nodule cases (~9000) is limited.