a strong trendP = 0.07
There was a good correlation between the NMR peak heights and the assayed levels of xanthurenic acid (r = 0.73 [Spearman's correlation coefficient], P = 0.001) and a strong trend in the results for glutamine (r = 0.46 [Spearman's correlation coefficient], P = 0.07), which helped to validate our interpretation of the NMR data.