diff --git a/HowBadIsMyBatch.ipynb b/HowBadIsMyBatch.ipynb
index fb9f35fd4e7..a6af80f8c9d 100644
--- a/HowBadIsMyBatch.ipynb
+++ b/HowBadIsMyBatch.ipynb
@@ -125,11 +125,14 @@
     "\n",
     "class DataFrameFilter:\n",
     "    \n",
-    "    def filterByCovid19And(self, dataFrame, manufacturer = None, dose = None):\n",
-    "        return dataFrame[self._isCovid19(dataFrame) & self._isManufacturer(dataFrame, manufacturer) & self._isDose(dataFrame, dose)]\n",
+    "    def filterByCovid19(self, dataFrame):\n",
+    "        return dataFrame[self._isCovid19(dataFrame)]\n",
+    "\n",
+    "    def filterBy(self, dataFrame, manufacturer = None, dose = None):\n",
+    "        return dataFrame[self._isManufacturer(dataFrame, manufacturer) & self._isDose(dataFrame, dose)]\n",
     "\n",
     "    def filterForSevereEffects(self, dataFrame, dose):\n",
-    "        return self.filterByCovid19And(dataFrame, dose = dose)\n",
+    "        return self.filterBy(self.filterByCovid19(dataFrame), dose = dose)\n",
     "\n",
     "    def _isCovid19(self, dataFrame):\n",
     "        return dataFrame[\"VAX_TYPE\"] == \"COVID19\"\n",
@@ -237,7 +240,8 @@
     "\n",
     "    @staticmethod\n",
     "    def createBatchCodeTable(dataFrame : pd.DataFrame, manufacturer, dose):\n",
-    "        filteredDataFrame = DataFrameFilter().filterByCovid19And(dataFrame, manufacturer = manufacturer, dose = dose)\n",
+    "        dataFrame = DataFrameFilter().filterByCovid19(dataFrame)\n",
+    "        filteredDataFrame = DataFrameFilter().filterBy(dataFrame, manufacturer = manufacturer, dose = dose)\n",
     "        return BatchCodeTableHelper(filteredDataFrame).createBatchCodeTable()\n",
     "\n",
     "    # create table from https://www.howbadismybatch.com/combined.html\n",
@@ -313,7 +317,7 @@
     "\n",
     "class DataFrameFilterTest(unittest.TestCase):\n",
     "\n",
-    "    def test_filterByCovid19And(self):\n",
+    "    def test_filterByCovid19_filterBy(self):\n",
     "        # Given\n",
     "        dataFrame = VaersDescr2DataFrameConverter.createDataFrameFromDescrs(\n",
     "            [\n",
@@ -321,14 +325,14 @@
     "                    'VAERSDATA': self.createDataFrame(\n",
     "                        columns = ['DIED', 'L_THREAT', 'DISABLE'],\n",
     "                        data = [  [1,      0,          0],\n",
-    "                                    [0,      0,          1]],\n",
+    "                                  [0,      0,          1]],\n",
     "                        index = [\n",
     "                            \"0916600\",\n",
     "                            \"0916601\"]),\n",
     "                    'VAERSVAX': self.createDataFrame(\n",
     "                        columns = ['VAX_TYPE', 'VAX_MANU', 'VAX_LOT', 'VAX_DOSE_SERIES'],\n",
     "                        data = [  ['COVID19',  'MODERNA',  '037K20A', '1'],\n",
-    "                                    ['COVID19',  'MODERNA',  '025L20A', '1']],\n",
+    "                                  ['COVID19',  'MODERNA',  '025L20A', '1']],\n",
     "                        index = [\n",
     "                            \"0916600\",\n",
     "                            \"0916601\"],\n",
@@ -338,14 +342,14 @@
     "                        'VAERSDATA': self.createDataFrame(\n",
     "                        columns = ['DIED', 'L_THREAT', 'DISABLE'],\n",
     "                        data = [  [0,       0,         0],\n",
-    "                                    [0,       0,         1]],\n",
+    "                                  [0,       0,         1]],\n",
     "                            index = [\n",
     "                            \"1996873\",\n",
     "                            \"1996874\"]),\n",
     "                        'VAERSVAX': self.createDataFrame(\n",
     "                            columns = ['VAX_TYPE', 'VAX_MANU',         'VAX_LOT', 'VAX_DOSE_SERIES'],\n",
     "                            data = [  ['HPV9',     'MERCK & CO. INC.', 'R017624', 'UNK'],\n",
-    "                                        ['COVID19',  'MODERNA',          '025L20A', '1']],\n",
+    "                                      ['COVID19',  'MODERNA',          '025L20A', '1']],\n",
     "                            index = [\n",
     "                                \"1996873\",\n",
     "                                \"1996874\"],\n",
@@ -355,7 +359,8 @@
     "        dataFrameFilter = DataFrameFilter()\n",
     "            \n",
     "        # When\n",
-    "        dataFrame = dataFrameFilter.filterByCovid19And(dataFrame, manufacturer = \"MODERNA\", dose = '1')\n",
+    "        dataFrame = dataFrameFilter.filterByCovid19(dataFrame)\n",
+    "        dataFrame = dataFrameFilter.filterBy(dataFrame, manufacturer = \"MODERNA\", dose = '1')\n",
     "        \n",
     "        # Then\n",
     "        dataFrameExpected = self.createDataFrame(\n",
@@ -378,14 +383,14 @@
     "                    'VAERSDATA': self.createDataFrame(\n",
     "                        columns = ['DIED', 'L_THREAT', 'DISABLE', 'HOSPITAL', 'ER_VISIT'],\n",
     "                        data = [  [1,      1,          0,         1,          1],\n",
-    "                                    [0,      0,          1,         0,          1]],\n",
+    "                                  [0,      0,          1,         0,          1]],\n",
     "                        index = [\n",
     "                            \"0916600\",\n",
     "                            \"0916601\"]),\n",
     "                    'VAERSVAX': self.createDataFrame(\n",
     "                        columns = ['VAX_TYPE', 'VAX_MANU',        'VAX_LOT', 'VAX_DOSE_SERIES'],\n",
     "                        data = [  ['COVID19',  'MODERNA',         '037K20A', '1'],\n",
-    "                                    ['COVID19',  'PFIZER\\BIONTECH', '025L20A', '1']],\n",
+    "                                  ['COVID19',  'PFIZER\\BIONTECH', '025L20A', '1']],\n",
     "                        index = [\n",
     "                            \"0916600\",\n",
     "                            \"0916601\"],\n",
@@ -421,7 +426,7 @@
     "                    'VAERSVAX': self.createDataFrame(\n",
     "                        columns = ['VAX_TYPE', 'VAX_MANU', 'VAX_LOT', 'VAX_DOSE_SERIES'],\n",
     "                        data = [  ['COVID19',  'MODERNA',  '016M20A', '2'],\n",
-    "                                    ['COVID19',  'MODERNA',  '030L20A', '1']],\n",
+    "                                  ['COVID19',  'MODERNA',  '030L20A', '1']],\n",
     "                        index = [\n",
     "                            \"1048786\",\n",
     "                            \"1048786\"],\n",
@@ -431,7 +436,8 @@
     "        dataFrameFilter = DataFrameFilter()\n",
     "            \n",
     "        # When\n",
-    "        dataFrame = dataFrameFilter.filterByCovid19And(dataFrame, manufacturer = \"MODERNA\", dose = '1')\n",
+    "        dataFrame = dataFrameFilter.filterByCovid19(dataFrame)\n",
+    "        dataFrame = dataFrameFilter.filterBy(dataFrame, manufacturer = \"MODERNA\", dose = '1')\n",
     "        \n",
     "        # Then\n",
     "        dataFrameExpected = self.createDataFrame(\n",
@@ -455,7 +461,7 @@
     "                    'VAERSVAX': self.createDataFrame(\n",
     "                        columns = ['VAX_TYPE', 'VAX_MANU', 'VAX_LOT', 'VAX_DOSE_SERIES'],\n",
     "                        data = [  ['COVID19',  'MODERNA',  '016M20A',  '2'],\n",
-    "                                    ['COVID19',  'MODERNA',  '030L20A',  '1']],\n",
+    "                                  ['COVID19',  'MODERNA',  '030L20A',  '1']],\n",
     "                        index = [\n",
     "                            \"1048786\",\n",
     "                            \"1048786\"],\n",
@@ -465,7 +471,8 @@
     "        dataFrameFilter = DataFrameFilter()\n",
     "\n",
     "        # When\n",
-    "        dataFrame = dataFrameFilter.filterByCovid19And(dataFrame, manufacturer = \"MODERNA\", dose = '2')\n",
+    "        dataFrame = dataFrameFilter.filterByCovid19(dataFrame)\n",
+    "        dataFrame = dataFrameFilter.filterBy(dataFrame, manufacturer = \"MODERNA\", dose = '2')\n",
     "        \n",
     "        # Then\n",
     "        dataFrameExpected = self.createDataFrame(\n",
@@ -618,7 +625,7 @@
     "                \"1048786\",\n",
     "                \"4711\"],\n",
     "                dtypes = {'VAX_DOSE_SERIES': \"string\"})\n",
-    "        dataFrame = DataFrameFilter().filterByCovid19And(dataFrame)\n",
+    "        dataFrame = DataFrameFilter().filterByCovid19(dataFrame)\n",
     "        \n",
     "        # When\n",
     "        doseTable = DoseAnalysis.getDoseTable(dataFrame)\n",
@@ -649,7 +656,7 @@
     "                \"1048786\",\n",
     "                \"4711\"],\n",
     "            dtypes = {'VAX_DOSE_SERIES': \"string\"})\n",
-    "        dataFrame = DataFrameFilter().filterByCovid19And(dataFrame)\n",
+    "        dataFrame = DataFrameFilter().filterByCovid19(dataFrame)\n",
     "        \n",
     "        # When\n",
     "        doseByMonthTable = DoseAnalysis.getDoseByMonthTable(dataFrame)\n",
@@ -812,13 +819,13 @@
     "def getDoseTable():\n",
     "    vaersDescrs = VaersDescrReader(dataDir = \"VAERS\").readAllVaersDescrs()\n",
     "    dataFrame = VaersDescr2DataFrameConverter.createDataFrameFromDescrs(vaersDescrs)\n",
-    "    dataFrame = DataFrameFilter().filterByCovid19And(dataFrame)\n",
+    "    dataFrame = DataFrameFilter().filterByCovid19(dataFrame)\n",
     "    return DoseAnalysis.getDoseTable(dataFrame)\n",
     "\n",
     "def getDoseByMonthTable():\n",
     "    vaersDescrs = VaersDescrReader(dataDir = \"VAERS\").readAllVaersDescrs()\n",
     "    dataFrame = VaersDescr2DataFrameConverter.createDataFrameFromDescrs(vaersDescrs)\n",
-    "    dataFrame = DataFrameFilter().filterByCovid19And(dataFrame)\n",
+    "    dataFrame = DataFrameFilter().filterByCovid19(dataFrame)\n",
     "    return DoseAnalysis.getDoseByMonthTable(dataFrame)"
    ]
   },