Terminology and diagnostic criteria used in studies investigating patients with subacromial pain syndrome from 1972 to 2019: a scoping review.

The terminology varied considerably across studies and time. The diagnostic criteria were often based on a cluster of physical examination tests. Imaging was primarily used to exclude other pathologies but was not used consistently. Patients with full-thickness supraspinatus tears were most often excluded. In summary, studies investigating SAPS are heterogeneous to an extent that makes it difficult, and often impossible, to compare studies.