Complex sentence: I/O psychology is a very broad field that sometimes covers topics also studied more intensively in other fields such as human factors and ergonomics, occupational health psychology, and organizational behavior and human resources.
Split into simpler sentences: I/O psychology is a very broad field that covers topics also studied in other fields. In particular the content of I/O psychology overlaps with the fields of human factors and ergonomics, occupational health psychology, and organizational behavior and human resources.