- Correlation coefficients for age and test results conducted with Spearman correlation. Only significant correlation coefficients are colored. Yellow boxes for coefficients ≥0.1 to <0.2, orange boxes for ≥0.2 to <0.3, red boxes for ≥0.3. *Correlation is significant at the 0.05 level, **correlation is significant at the 0.01 level ***correlation is significant at the 0.001 level