Clustering is most often done among observations, not variables. Proc VARCLUS is the only SAS procedure for clustering variables but does not allow for user-defined distance measures. The method proposed is for clustering variables based on Spearman correlations with proc CLUSTER, a procedure which requires distances.   I have suggested PROC CLUSTER METHOD=FLEXIBLE because it has given me useful results for similar problems. That doesn't prevent you from exploring other options at your will. No clustering method is universally the best. I'd be interested to know what method you chose in the end.    ... View more