diff --git a/maud/data_model/parameter_set.py b/maud/data_model/parameter_set.py
index be84cea2..cc207c75 100644
--- a/maud/data_model/parameter_set.py
+++ b/maud/data_model/parameter_set.py
@@ -169,7 +169,6 @@ def _get_experiments(self, train: bool) -> list[str]:
         ]
 
     def _get_drain(self, train: bool) -> mp.Drain:
-        """Add the drain_train field."""
         drain_ids = [
             d.id
             for d in self.kinetic_model.reactions
@@ -281,12 +280,12 @@ def _get_conc_pme(self, train: bool) -> mp.ConcPme:
     @computed_field
     def conc_pme_train(self) -> mp.ConcPme:
         """Add the conc_pme_train field."""
-        return self._get_conc_pme(True)
+        return self._get_conc_pme(train=True)
 
     @computed_field
     def conc_pme_test(self) -> mp.ConcPme:
         """Add the conc_pme_test field."""
-        return self._get_conc_pme(False)
+        return self._get_conc_pme(train=False)
 
     def _get_psi(self, train: bool) -> mp.Psi:
         """Add the psi_train field."""
@@ -311,4 +310,4 @@ def psi_train(self) -> mp.Psi:
     @computed_field
     def psi_test(self) -> mp.Psi:
         """Add the psi_test field."""
-        return self._get_psi(train=True).test()
+        return self._get_psi(train=False)