diff --git a/src/nt/ntaggregate.cpp b/src/nt/ntaggregate.cpp
index 071c7be..d4879a0 100644
--- a/src/nt/ntaggregate.cpp
+++ b/src/nt/ntaggregate.cpp
@@ -278,6 +278,11 @@ bool NTAggregate::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTAggregate::isValid()
+{
+    return true;
+}
+
 NTAggregateBuilderPtr NTAggregate::createBuilder()
 {
     return NTAggregateBuilderPtr(new detail::NTAggregateBuilder());
diff --git a/src/nt/ntattribute.cpp b/src/nt/ntattribute.cpp
index ae0c418..d8cfa49 100644
--- a/src/nt/ntattribute.cpp
+++ b/src/nt/ntattribute.cpp
@@ -175,6 +175,11 @@ bool NTAttribute::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTAttribute::isValid()
+{
+    return true;
+}
+
 NTAttributeBuilderPtr NTAttribute::createBuilder()
 {
     return NTAttributeBuilderPtr(new detail::NTAttributeBuilder());
diff --git a/src/nt/ntcontinuum.cpp b/src/nt/ntcontinuum.cpp
index 34817d5..5eb2866 100644
--- a/src/nt/ntcontinuum.cpp
+++ b/src/nt/ntcontinuum.cpp
@@ -161,6 +161,11 @@ bool NTContinuum::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTContinuum::isValid()
+{
+    return ((getUnits()->getLength()-1)*getBase()->getLength() ==
+            getValue()->getLength());
+}
 
 NTContinuumBuilderPtr NTContinuum::createBuilder()
 {
diff --git a/src/nt/ntenum.cpp b/src/nt/ntenum.cpp
index b99a028..2ee0d44 100644
--- a/src/nt/ntenum.cpp
+++ b/src/nt/ntenum.cpp
@@ -154,6 +154,11 @@ bool NTEnum::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTEnum::isValid()
+{
+    return true;
+}
+
 NTEnumBuilderPtr NTEnum::createBuilder()
 {
     return NTEnumBuilderPtr(new detail::NTEnumBuilder());
diff --git a/src/nt/nthistogram.cpp b/src/nt/nthistogram.cpp
index 303e63c..08ca949 100644
--- a/src/nt/nthistogram.cpp
+++ b/src/nt/nthistogram.cpp
@@ -171,6 +171,10 @@ bool NTHistogram::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTHistogram::isValid()
+{
+    return (getValue()->getLength()+1 == getRanges()->getLength());
+}
 
 NTHistogramBuilderPtr NTHistogram::createBuilder()
 {
diff --git a/src/nt/ntmatrix.cpp b/src/nt/ntmatrix.cpp
index 3470d5b..a809946 100644
--- a/src/nt/ntmatrix.cpp
+++ b/src/nt/ntmatrix.cpp
@@ -181,6 +181,31 @@ bool NTMatrix::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTMatrix::isValid()
+{
+    int valueLength = getValue()->getLength();
+    if (valueLength == 0)
+        return false;
+
+    PVIntArrayPtr pvDim = getDim();
+    if (pvDim.get())
+    {
+        int length = pvDim->getLength();
+        if (length != 1 && length !=2)
+            return false;
+
+        PVIntArray::const_svector data = pvDim->view();
+        int expectedLength = 1;
+        for (PVIntArray::const_svector::const_iterator it = data.begin();
+                 it != data.end(); ++it)
+        {
+             expectedLength *= *it;
+        }
+        if (expectedLength != valueLength)
+        return false;
+    }
+    return true;
+}
 
 NTMatrixBuilderPtr NTMatrix::createBuilder()
 {
diff --git a/src/nt/ntnameValue.cpp b/src/nt/ntnameValue.cpp
index 7a6590d..4128768 100644
--- a/src/nt/ntnameValue.cpp
+++ b/src/nt/ntnameValue.cpp
@@ -168,6 +168,11 @@ bool NTNameValue::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTNameValue::isValid()
+{
+    return (getValue<PVScalarArray>()->getLength() == getName()->getLength());
+}
+
 NTNameValueBuilderPtr NTNameValue::createBuilder()
 {
     return NTNameValueBuilderPtr(new detail::NTNameValueBuilder());
diff --git a/src/nt/ntndarrayAttribute.cpp b/src/nt/ntndarrayAttribute.cpp
index 60dcd2e..44e647e 100644
--- a/src/nt/ntndarrayAttribute.cpp
+++ b/src/nt/ntndarrayAttribute.cpp
@@ -158,6 +158,11 @@ bool NTNDArrayAttribute::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTNDArrayAttribute::isValid()
+{
+    return true;
+}
+
 NTNDArrayAttributeBuilderPtr NTNDArrayAttribute::createBuilder()
 {
     return NTNDArrayAttributeBuilderPtr(new detail::NTNDArrayAttributeBuilder());
diff --git a/src/nt/ntscalar.cpp b/src/nt/ntscalar.cpp
index e9d64ca..e51af6c 100644
--- a/src/nt/ntscalar.cpp
+++ b/src/nt/ntscalar.cpp
@@ -193,6 +193,11 @@ bool NTScalar::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTScalar::isValid()
+{
+    return true;
+}
+
 NTScalarBuilderPtr NTScalar::createBuilder()
 {
     return NTScalarBuilderPtr(new detail::NTScalarBuilder());
diff --git a/src/nt/ntscalarArray.cpp b/src/nt/ntscalarArray.cpp
index 8dfea9c..ba7abf5 100644
--- a/src/nt/ntscalarArray.cpp
+++ b/src/nt/ntscalarArray.cpp
@@ -189,6 +189,10 @@ bool NTScalarArray::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTScalarArray::isValid()
+{
+    return true;
+}
 
 NTScalarArrayBuilderPtr NTScalarArray::createBuilder()
 {
diff --git a/src/nt/ntunion.cpp b/src/nt/ntunion.cpp
index b4ddd86..c873b7a 100644
--- a/src/nt/ntunion.cpp
+++ b/src/nt/ntunion.cpp
@@ -154,6 +154,11 @@ bool NTUnion::isCompatible(PVStructurePtr const & pvStructure)
     return isCompatible(pvStructure->getStructure());
 }
 
+bool NTUnion::isValid()
+{
+    return true;
+}
+
 NTUnionBuilderPtr NTUnion::createBuilder()
 {
     return NTUnionBuilderPtr(new detail::NTUnionBuilder());