diff --git a/include/psa/crypto_extra.h b/include/psa/crypto_extra.h
index 0c90cb2d1..b25addc85 100644
--- a/include/psa/crypto_extra.h
+++ b/include/psa/crypto_extra.h
@@ -231,8 +231,8 @@ typedef struct mbedtls_psa_stats_s
     size_t cache_slots;
     /** Number of slots that are not used for anything. */
     size_t empty_slots;
-    /** Number of slots that are not locked. */
-    size_t unlocked_slots;
+    /** Number of slots that are locked. */
+    size_t locked_slots;
     /** Largest key id value among open keys in internal persistent storage. */
     psa_key_id_t max_open_internal_key_id;
     /** Largest key id value among open keys in secure elements. */
diff --git a/library/psa_crypto_slot_management.c b/library/psa_crypto_slot_management.c
index 3e1866871..1d2e51fec 100644
--- a/library/psa_crypto_slot_management.c
+++ b/library/psa_crypto_slot_management.c
@@ -438,9 +438,9 @@ void mbedtls_psa_get_stats( mbedtls_psa_stats_t *stats )
     for( slot_idx = 0; slot_idx < PSA_KEY_SLOT_COUNT; slot_idx++ )
     {
         const psa_key_slot_t *slot = &global_data.key_slots[ slot_idx ];
-        if( ! psa_is_key_slot_locked( slot ) )
+        if( psa_is_key_slot_locked( slot ) )
         {
-            ++stats->unlocked_slots;
+            ++stats->locked_slots;
         }
         if( ! psa_is_key_slot_occupied( slot ) )
         {
diff --git a/tests/include/test/psa_crypto_helpers.h b/tests/include/test/psa_crypto_helpers.h
index 09171ae76..01b0547cf 100644
--- a/tests/include/test/psa_crypto_helpers.h
+++ b/tests/include/test/psa_crypto_helpers.h
@@ -41,7 +41,7 @@ static int test_helper_is_psa_pristine( int line, const char *file )
         msg = "An external slot has not been closed properly.";
     else if( stats.half_filled_slots != 0 )
         msg = "A half-filled slot has not been cleared properly.";
-    else if( stats.unlocked_slots != PSA_KEY_SLOT_COUNT )
+    else if( stats.locked_slots != 0 )
     {
         msg = "Some slots are still marked as locked.";
     }