a significant trendp = 0.02
When dividing IgM anti-PC levels into quartiles, there was a significant trend across the quartiles for the presence of multi-vessel disease with decreased levels of IgM anti-PC (p = 0.02), identifying a threshold for IgM anti-PC at the 25 percentiles, 24.6 U/ml, thus IgM anti-PC were divided into high and low levels at the 25 percentiles.