# Is it appropriate to infer from spearman correlation with 3-level ordinal variable?

Suppose I have the data of 300 patients containing their age and grade of tumor at the diagnosis. The grading has only 3 levels: Grade 1, Grade 2 and Grade 3.

Is it appropriate to use Spearman correlation to infer if the age was associated initial tumor grade?

Would it be better than one-way ANOVA with post-hoc tests? (treating grading as subgroups)

• You might look into Kendall's tau-b or tau-c for correlations of data with ties or discrete values. Sep 30, 2019 at 13:25