Microscopic examination

Gram staining and microscopic examinations were performed according to standardized methods. For each specimen, 10 µL of the sample was smeared onto a glass slide and stained using the Hucker method. Without prior knowledge of the bacterial species, two examiners independently examined the slides at a magnification of 1000×, observing 20–40 fields per specimen. Examiner 1 (TH) is a physician in the Department of Infectious Diseases with 9 years of experience in Gram staining, including routine microscopic interpretation of blood culture specimens. Examiner 2 (MY) is a clinical laboratory technician in the Department of Microbiology with 14 years of experience, routinely performing Gram staining microscopy. After their examination, two novice physicians, one in Postgraduate Year 1 (PGY-1) and one in Postgraduate Year 2 (PGY-2), used the STAPH score to evaluate the last 40 samples collected during the study period. This was performed to assess how effectively novice physicians could use the STAPH score to identify SA.