diff --git a/src/mlpack/methods/dbscan/dbscan.hpp b/src/mlpack/methods/dbscan/dbscan.hpp
index 0a237ae1a6..edbe30881c 100644
--- a/src/mlpack/methods/dbscan/dbscan.hpp
+++ b/src/mlpack/methods/dbscan/dbscan.hpp
@@ -85,7 +85,8 @@ class DBSCAN
 
   /**
    * Performs DBSCAN clustering on the data, returning number of clusters
-   * and also the list of cluster assignments.
+   * and also the list of cluster assignments.  If assignments[i] == SIZE_MAX,
+   * then the point is considered "noise".
    *
    * @tparam MatType Type of matrix (arma::mat or arma::sp_mat).
    * @param data Dataset to cluster.
@@ -98,8 +99,7 @@ class DBSCAN
   /**
    * Performs DBSCAN clustering on the data, returning number of clusters,
    * the centroid of each cluster and also the list of cluster assignments.
-   * If assignments[i] == assignments.n_elem - 1, then the point is considered
-   * "noise".
+   * If assignments[i] == SIZE_MAX, then the point is considered "noise".
    *
    * @tparam MatType Type of matrix (arma::mat or arma::sp_mat).
    * @param data Dataset to cluster.