All media require collection of an adequate sample of infected material. Scale may be collected in a manner similar to that used for the KOH preparation or with a cotton swab. The swab must first be moistened with sterile water and then rubbed vigorously over the active border of the lesion. This method is best used when the lesion is not scaly or when the use of a blade or slide is impractical. 19 The physician performing the culture must comply with stricter CLIA regulations. Performing cultures requires a level of certification that necessitates a laboratory inspection.