“…For this study, the U.S. Food and Drug Administration Establishment Registration and Device Listing database was used to identify FDA-cleared over-the-counter hearing aids in August 2023, as shown in Figure 1 [29]. The database was searched for devices with product codes QUF, QUG, QUH, and QDD, which identify hearing aids for sale without a prescription [30]. All companies with devices registered with these product codes were extracted from the database in August 2023.…”