Figure 1.

Distribution of protein levels detected in 60 human tear samples with PSM ≥2 and detection in >5% of samples. The x-axis portrays the detection frequency of each protein, and the y-axis portrays the average protein levels (quantified by PSMs). These proteins were classified based on their abundance into four groups: high abundance (157 proteins, detected in ≥75% of samples), medium (109 proteins, 50%–75% of samples), low (301 proteins, 25%–50% of samples), and rare (2243 proteins, 5%–25% of samples).