diff --git a/src/modality-specific-files/magnetic-resonance-spectroscopy.md b/src/modality-specific-files/magnetic-resonance-spectroscopy.md
index 0c6e547b62..55088a5f85 100644
--- a/src/modality-specific-files/magnetic-resonance-spectroscopy.md
+++ b/src/modality-specific-files/magnetic-resonance-spectroscopy.md
@@ -202,10 +202,11 @@ A guide for using macros can be found at
  https://github.com/bids-standard/bids-specification/blob/master/macros_doc.md
 -->
 {{ MACROS___make_sidecar_table([
-  "mrs.MRSRecommendedFields",
   "mrs.MRSRecommendedFieldsNumTransients",
-  "mrs.MRSRecommendedFieldsAnatomicalImage",
-  "mrs.MRSIRecommendedFields"
+  "mrs.MRSRecommendedFields",
+  "mrs.MRSIRecommendedFields",
+  "mrs.MRSRecommendedFieldsRefSignal",
+  "mrs.MRSRecommendedFieldsAnatomicalImage"
   ])
 }}
 
diff --git a/src/schema/rules/sidecars/mrs.yaml b/src/schema/rules/sidecars/mrs.yaml
index 7ac11a6697..7524053ec7 100644
--- a/src/schema/rules/sidecars/mrs.yaml
+++ b/src/schema/rules/sidecars/mrs.yaml
@@ -45,7 +45,6 @@ MRSSequenceSpecifics:
     ScanningSequence__mrs: recommended
     SequenceName: recommended
     PulseSequenceDetails: recommended
-    MRAcquisitionType: optional, but recommended for MRSI
     WaterSuppression: recommended
     WaterSuppressionTechnique: optional
     OuterVolumeSuppression: optional
@@ -74,14 +73,15 @@ MRSRecommendedFields:
     MatrixSize: recommended for MRSI
     VolumeAffineMatrix: recommended for MRSI
     EncodingTechnique: recommended for MRSI
-    ReferenceSignal: recommended if MRS reference data are present
 
 MRSRecommendedFieldsAnatomicalImage:
   selectors:
     - modality == "mrs"
-    - '"anat" in dataset.datatypes'
+    - intersects(dataset.datatypes, ["anat"])
   fields:
-    AnatomicalImage: recommended
+    AnatomicalImage:
+      level: recommended
+      level_addendum: if anatomical MRI data are present
 
 MRSRecommendedFieldsNumTransients:
   selectors:
@@ -90,12 +90,23 @@ MRSRecommendedFieldsNumTransients:
   fields:
     NumberOfTransients: recommended
 
+MRSRecommendedFieldsRefSignal:
+  selectors:
+    - modality == "mrs"
+    - intersects([suffix], ["mrsref"])
+  fields:
+    ReferenceSignal:
+      level: recommended
+      level_addendum: if MRS reference data are present
+
 MRSIRecommendedFields:
   selectors:
     - modality == "mrs"
     - suffix == "mrsi"
   fields:
-    MRAcquisitionType: recommended
+    MRAcquisitionType:
+      level: recommended
+      level_addendum: for MRSI
 
 MRSOptionalFields:
   selectors: