diff --git a/PROR/PROR.sql b/PROR/PROR.sql
index 7ab1d98d2..7accdbc73 100644
--- a/PROR/PROR.sql
+++ b/PROR/PROR.sql
@@ -514,7 +514,7 @@ AS
         AND pk.prs_kenmerk_upper='AFAS ACCOUNT'
         AND kl.prs_kenmerk_key = pk.prs_kenmerk_key
         AND kl.prs_link_key=p.prs_perslid_key
-        AND kl.prs_kenmerklink_waarde=1
+        AND kl.prs_kenmerklink_waarde='1'
         AND NOT EXISTS (SELECT 'x'
                           FROM fac_gebruikersgroep f
                          WHERE f.prs_perslid_key=p.prs_perslid_key);