diff --git a/src/main/scala/ALSAlgorithm.scala b/src/main/scala/ALSAlgorithm.scala
index e01d31d..67dc32a 100644
--- a/src/main/scala/ALSAlgorithm.scala
+++ b/src/main/scala/ALSAlgorithm.scala
@@ -265,6 +265,7 @@
 
     val itemScores = topScores.map { case (i, s) =>
       new ItemScore(
+        // convert item int index back to string ID
         item = model.itemIntStringMap(i),
         score = s
       )