diff --git a/Framework/Algorithms/src/ExtractSpectra.cpp b/Framework/Algorithms/src/ExtractSpectra.cpp
index be0c56fb5315831f95cd89fd234491521017a44f..c6c92793416388c57e79c70c7ea08e191cb8b3d9 100644
--- a/Framework/Algorithms/src/ExtractSpectra.cpp
+++ b/Framework/Algorithms/src/ExtractSpectra.cpp
@@ -339,7 +339,7 @@ void ExtractSpectra::execEvent() {
       outEL.setX(XValues_new.cowData());
       if (hasDx) {
         auto &oldDx = m_inputWorkspace->dx(i);
-        outEL.setCountStandardDeviations(oldDx.begin() + m_minX,
+        outEL.setPointStandardDeviations(oldDx.begin() + m_minX,
                                          oldDx.begin() + m_maxX - m_histogram);
       }
     }
diff --git a/Framework/Algorithms/src/TOFSANSResolution.cpp b/Framework/Algorithms/src/TOFSANSResolution.cpp
index c11cb1daa8fca26d8029d0e5ea01cb481c03ca0d..920be30f525a6d60d5d2897d402532c6450387e6 100644
--- a/Framework/Algorithms/src/TOFSANSResolution.cpp
+++ b/Framework/Algorithms/src/TOFSANSResolution.cpp
@@ -248,7 +248,7 @@ void TOFSANSResolution::exec() {
     TOFY[i] /= XNorm[i];
     ThetaY[i] /= XNorm[i];
   }
-  iqWS->histogram(0).setPointStandardDeviations(std::move(DxOut));
+  iqWS->setPointStandardDeviations(0, std::move(DxOut));
 }
 } // namespace Algorithms
 } // namespace Mantid
diff --git a/Framework/DataHandling/src/SavePDFGui.cpp b/Framework/DataHandling/src/SavePDFGui.cpp
index c0c53bb3104b74ecf3f9cbe12fa4a22e2b5c9d7e..853343525347e1222f84ca18d39f00a7eacc9dc9 100644
--- a/Framework/DataHandling/src/SavePDFGui.cpp
+++ b/Framework/DataHandling/src/SavePDFGui.cpp
@@ -108,8 +108,8 @@ void SavePDFGui::exec() {
   auto y = inputWS->readY(0);
   auto dy = inputWS->readE(0);
   HistogramData::HistogramDx dx(y.size(), 0.0);
-  if (inputWS->histogram(0).sharedDx())
-    dx = inputWS->histogram(0).dx();
+  if (inputWS->sharedDx(0))
+    dx = inputWS->dx(0);
   const size_t length = x.size();
   for (size_t i = 0; i < length; ++i) {
     out << "  " << x[i] << "  " << y[i] << "  " << dx[i] << "  " << dy[i]
diff --git a/Framework/DataObjects/test/EventListTest.h b/Framework/DataObjects/test/EventListTest.h
index 0110b8b106657e01bca93f49e83a4ed6da81bea9..5fb4fbc9e16fabc4e681a7d33e4945dddecb5bd4 100644
--- a/Framework/DataObjects/test/EventListTest.h
+++ b/Framework/DataObjects/test/EventListTest.h
@@ -68,8 +68,8 @@ public:
     // Modify EventList such that is does not contain default values.
     el.setSpectrumNo(42);
     MantidVec x{0.1, 0.2, 0.3};
-    el.histogram() = Histogram(BinEdges(x));
-    el.histogram().setPointVariances(2);
+    el.setX(make_cow<HistogramX>(x));
+    el.setPointVariances(2);
 
     EventList other;
     other = el;
diff --git a/Framework/HistogramData/test/HistogramTest.h b/Framework/HistogramData/test/HistogramTest.h
index 705d199c4484e38bcda079d8a8338f0f09d3816d..f598a249ac380bdbcb79746bc2ff5efacdbe788b 100644
--- a/Framework/HistogramData/test/HistogramTest.h
+++ b/Framework/HistogramData/test/HistogramTest.h
@@ -834,6 +834,7 @@ public:
     Histogram hist{BinEdges(0)};
     hist.setCountStandardDeviations(data1);
     TS_ASSERT_THROWS(hist.setSharedE(data2), std::logic_error);
+  }
 
   void test_setPointStandardDeviations_point_data() {
     Histogram hist(Points(2));
diff --git a/Framework/Nexus/src/NexusFileIO.cpp b/Framework/Nexus/src/NexusFileIO.cpp
index 565f95676916ef65a21dc179c6956f7a89c6b1f4..ec7622a767a481d7324a5180a0d8919ea140a6d1 100644
--- a/Framework/Nexus/src/NexusFileIO.cpp
+++ b/Framework/Nexus/src/NexusFileIO.cpp
@@ -405,8 +405,7 @@ int NexusFileIO::writeNexusProcessedData2D(
     // Potentially x error
     if (localworkspace->hasDx(0)) {
       dims_array[0] = static_cast<int>(nSpect);
-      dims_array[1] =
-          static_cast<int>(localworkspace->histogram(0).dx().size());
+      dims_array[1] = static_cast<int>(localworkspace->dx(0).size());
       std::string dxErrorName = "xerrors";
       NXcompmakedata(fileID, dxErrorName.c_str(), NX_FLOAT64, 2, dims_array,
                      m_nexuscompression, asize);