diff --git a/core/qa/checker/CbmQaCheckerCore.cxx b/core/qa/checker/CbmQaCheckerCore.cxx
index 7af9029e32e207fe5b7609cf1d5fe09f46d3bb02..17eff8f3a4b2adef80ae699fbcce3138e5fd075c 100644
--- a/core/qa/checker/CbmQaCheckerCore.cxx
+++ b/core/qa/checker/CbmQaCheckerCore.cxx
@@ -14,12 +14,11 @@
 #include "Logger.h"
 
 #include "TClonesArray.h"
+#include "TFile.h"
 #include "TFolder.h"
 //#include <boost/filesystem.hpp>
 #include <regex>
 
-#include <yaml-cpp/yaml.h>
-
 using cbm::qa::checker::Core;
 
 // ---------------------------------------------------------------------------------------------------------------------
diff --git a/core/qa/checker/CbmQaCheckerCore.h b/core/qa/checker/CbmQaCheckerCore.h
index e44233d276d7e6326da4e3656ee7cabb8fc73220..bb7c73981b96b3e3e0a217c568b5cef64e4b79d3 100644
--- a/core/qa/checker/CbmQaCheckerCore.h
+++ b/core/qa/checker/CbmQaCheckerCore.h
@@ -13,14 +13,14 @@
 #include "CbmQaCheckerObjectDB.h"
 #include "CbmQaCheckerTypedefs.h"
 
-#include "TFile.h"
+#include "Rtypes.h"
 
-#include <bitset>
 #include <memory>
 #include <string>
-#include <unordered_map>
 #include <vector>
 
+class TFile;
+
 namespace cbm::qa::checker
 {
   /// @brief Core class for CBM QA checker framework (declaration)
diff --git a/core/qa/checker/CbmQaCheckerFileHandler.cxx b/core/qa/checker/CbmQaCheckerFileHandler.cxx
index a28a8c99f1b6011f6495b1303d5ba81e330077f9..75c8d0cd97d7f53b899f36399bf06970fb27f178 100644
--- a/core/qa/checker/CbmQaCheckerFileHandler.cxx
+++ b/core/qa/checker/CbmQaCheckerFileHandler.cxx
@@ -173,11 +173,12 @@ TNamed* FileHandler::ReadObjectFromFile(TFile* pFile, const std::string& path) c
   TObject* pObj = pFile;
   size_t iPos   = 0;  // Index of first symbol
   size_t iNext  = 0;  // Index of last symbol
+  // Read object iteratively, running throug directories or folders, provided by path
   while (iPos < path.size()) {
     // get name
     iNext = path.find_first_of('/', iPos);
     if (iNext > path.size()) { iNext = path.size(); }
-    std::string part = path.substr(iPos, iNext - iPos);
+    std::string part = path.substr(iPos, iNext - iPos);  // short name of next object/directory/folder in the path
     iPos             = iNext + 1;
     if (!part.size()) { continue; }
 
diff --git a/core/qa/checker/CbmQaCheckerFileHandler.h b/core/qa/checker/CbmQaCheckerFileHandler.h
index 0557ad3206d13231a301f98b83ab0753fc2e32bb..7f5e0ce862a371b2999131c11045f4903ddf40a5 100644
--- a/core/qa/checker/CbmQaCheckerFileHandler.h
+++ b/core/qa/checker/CbmQaCheckerFileHandler.h
@@ -19,7 +19,7 @@
 #include <vector>
 
 class TNamed;
-class TFolder;
+class TDirectory;
 class TFile;
 
 namespace cbm::qa::checker
@@ -72,7 +72,7 @@ namespace cbm::qa::checker
     /// @return  Pointer to created TDirectory object
     TDirectory* CreateNestedDirectory(const std::string& path);
 
-    /// @brief Reads object from file by the provided full path to the object.
+    /// @brief Iteratively reads object from file by the provided full path to the object
     /// @param pFile  Pointer to TFile instance
     /// @param path   Full path to the object inside the file
     /// @return A pointer to TNamed object
diff --git a/core/qa/checker/CbmQaCheckerObjectDB.cxx b/core/qa/checker/CbmQaCheckerObjectDB.cxx
index 99e03d9430e7337a2769ed3e5f23ab1615082e40..582c06ab679ea66e3e592569573d6f20a38100a0 100644
--- a/core/qa/checker/CbmQaCheckerObjectDB.cxx
+++ b/core/qa/checker/CbmQaCheckerObjectDB.cxx
@@ -15,6 +15,8 @@
 #include <regex>
 #include <sstream>
 
+#include <yaml-cpp/yaml.h>
+
 using cbm::qa::checker::ObjectDB;
 
 // ---------------------------------------------------------------------------------------------------------------------
@@ -224,7 +226,7 @@ void ObjectDB::ReadFromYAML(const char* configName)
 std::string ObjectDB::ToString() const
 {
   std::stringstream msg;
-  msg << "*** CBM QA-Checker: defied files ****\n\n";
+  msg << "*** CBM QA-Checker: defined files ****\n\n";
 
   msg << "----- Versions:\n";
   for (size_t iV = 0; iV < fvVersionLabels.size(); ++iV) {
diff --git a/core/qa/checker/CbmQaCheckerObjectDB.h b/core/qa/checker/CbmQaCheckerObjectDB.h
index 49eea504b998fe4fa7d89f94325cc7ca36b8351c..23619482c76382a45cbea5d178c1c36c836ca165 100644
--- a/core/qa/checker/CbmQaCheckerObjectDB.h
+++ b/core/qa/checker/CbmQaCheckerObjectDB.h
@@ -12,23 +12,10 @@
 
 #include "CbmQaCheckerTypedefs.h"
 
-#include "Logger.h"
-
 #include <string>
 #include <utility>
 #include <vector>
 
-#include <yaml-cpp/yaml.h>
-
-// TMP
-#include <boost/core/demangle.hpp>
-
-#include <typeinfo>
-template<typename T>
-std::string type_str()
-{
-  return boost::core::demangle(typeid(T).name());
-}
 
 namespace cbm::qa::checker
 {
@@ -70,27 +57,18 @@ namespace cbm::qa::checker
     /// @brief Gets name of dataset
     /// @param iDataset  Index of dataset
     /// @return  Name of dataset
-    const auto& GetDataset(int iDataset) const { return fvDatasets[iDataset]; }
-
-    /// @brief Gets reference to dataset name array
-    const auto& GetDatasets() const { return fvDatasets; }
+    const std::string& GetDataset(int iDataset) const { return fvDatasets[iDataset]; }
 
     /// @brief Gets index of default version
     /// @return  Index of default version
     int GetDefaultID() const { return fDefVersionID; }
 
-    /// @brief Gets label of the default version
-    const std::string& GetDefaultLabel() const
-    {
-      assert(fDefVersionID > -1);
-      return GetVersionLabel(fDefVersionID);
-    }
-
     /// @brief Gets label of file
     /// @param iFile  Index of file
     /// @return  Label of file
-    const auto& GetFileLabel(int iFile) const { return fvFileLabels[iFile]; }
+    const std::string& GetFileLabel(int iFile) const { return fvFileLabels[iFile]; }
 
+  private:
     /// @brief Gets iterator range for object names stored in a file
     /// @note  The iterator_range object behaves itself just like an ordinary STL container.
     /// @param iFile  Index of file
@@ -105,9 +83,11 @@ namespace cbm::qa::checker
 
       int iBegin = itBegin - fvGlobalToFileObject.begin();
       int iEnd   = itEnd - fvGlobalToFileObject.begin();
+
       return boost::make_iterator_range(fvObjects.begin() + iBegin, fvObjects.begin() + iEnd);
     }
 
+  public:
     /// @brief Gets comparison result
     /// @param iDS    Index of dataset
     /// @param iFile  Index of file
@@ -154,16 +134,10 @@ namespace cbm::qa::checker
     /// @param iVersion  Index of version
     const std::string& GetVersionLabel(int iVersion) const { return fvVersionLabels[iVersion]; }
 
-    /// @brief Gets reference to version label array
-    const auto& GetVersionLabels() const { return fvVersionLabels; }
-
     /// @brief Gets version path
     /// @param iVersion  Index of version
     const std::string& GetVersionPath(int iVersion) const { return fvVersionPaths[iVersion]; }
 
-    /// @brief Gets reference to version path array
-    const auto& GetVersionPaths() const { return fvVersionPaths; }
-
     /// @brief Initializes the database
     void Init();
 
diff --git a/macro/qa/CMakeLists.txt b/macro/qa/CMakeLists.txt
index ae6a55dd28fde42aab6dd3127473db54fe55d665..a08bf9ad7d5f989c981709737078f82f0ebb8eaf 100644
--- a/macro/qa/CMakeLists.txt
+++ b/macro/qa/CMakeLists.txt
@@ -49,11 +49,11 @@ endif()
 
 
 # =====   Cleanup the data directory   =======================================
-add_test(run_cleanup ${CMAKE_COMMAND}
+add_test(qa_cleanup ${CMAKE_COMMAND}
 	-P ${CMAKE_SOURCE_DIR}/cmake/scripts/cleanmacrodir.cmake)
-set_tests_properties(run_cleanup PROPERTIES
+set_tests_properties(qa_cleanup PROPERTIES
 	TIMEOUT ${timeOutTime}
-	FIXTURES_SETUP run_cleanup
+	FIXTURES_SETUP qa_cleanup
 )
 # ============================================================================
 
diff --git a/macro/qa/qa_compare.C b/macro/qa/qa_compare.C
index 80065154957743e430b4f763247dcff6a801b23b..ee32e588d9f1f54d901bbef1a9fa9bebf5a2ea30 100644
--- a/macro/qa/qa_compare.C
+++ b/macro/qa/qa_compare.C
@@ -23,9 +23,9 @@
 int qa_compare( 
                 const char* configName         = "objects.yaml",
                 const char* datasetName        = "s100e",
-                const char* oldVersionInputDir = "../run/data",       // NOTE: Files from external repository
-                const char* newVersionInputDir = "../run/data",       // NOTE: Files from preceding fixture
-                const char* outputName         = "QACheckerOutput.h"  // TODO: Add tag of a merge request or commit
+                const char* oldVersionInputDir = "../run/data",          // NOTE: Files from external repository
+                const char* newVersionInputDir = "../run/data",          // NOTE: Files from preceding fixture
+                const char* outputName         = "QACheckerOutput.root"  // TODO: Add tag of a merge request or commit
               )
 /* clang-format on */
 {