diff --git a/.github/workflows/test-changes.yml b/.github/workflows/test-changes.yml
index dc921e42..802dbceb 100644
--- a/.github/workflows/test-changes.yml
+++ b/.github/workflows/test-changes.yml
@@ -37,8 +37,7 @@ jobs:
     steps:
       - name: Determine what scope of testing is available on ${{ matrix.os }}
         if: |
-          matrix.python >= '3.6' && matrix.python != '3.9' && matrix.python != '3.10' &&
-          (matrix.os != 'windows-latest' || matrix.python == '3.8')
+          (matrix.python >= '3.' ) && ( matrix.os != 'windows-latest' )
         run: |
           echo 'testing=full' >> $GITHUB_ENV
 
@@ -59,7 +58,7 @@ jobs:
       - name: Install test dependencies
         run: |
           python -m pip install --upgrade pip
-          python -m pip install -r requirements-tests.txt
+          python -m pip install --prefer-binary -r requirements-tests.txt
 
       - name: Setup environment variables for remote filesystem testing
         if: matrix.os == 'ubuntu-latest' && matrix.python == '3.8'
@@ -69,7 +68,7 @@ jobs:
           echo "Setup SFTP environment variable to trigger testing in Petl"
           echo 'PETL_TEST_SFTP=sftp://petl:test@localhost:2244/public/' >> $GITHUB_ENV
           echo "::group::Install remote test dependencies"
-          python -m pip install -r requirements-remote.txt
+          python -m pip install --prefer-binary -r requirements-remote.txt
           echo "::endgroup::"
 
       - name: Install optinal test dependencies for mode ${{ env.testing }}
@@ -105,7 +104,7 @@ jobs:
           docker run -it --name postgres -p 5432:5432 -e POSTGRES_DB=petl -e POSTGRES_USER=petl -e POSTGRES_PASSWORD=test -d postgres:latest
           echo "::endgroup::"
           echo "::group::Install database test dependencies"
-          python -m pip install -r requirements-database.txt
+          python -m pip install --prefer-binary -r requirements-database.txt
           echo "::endgroup::"
 
       - name: Setup petl package
@@ -119,10 +118,10 @@ jobs:
         if: env.testing == 'full'
         run: |
           echo "::group::Install extra packages test dependencies"
-          python -m pip install -r requirements-formats.txt
+          python -m pip install --prefer-binary -r requirements-formats.txt
           echo "::endgroup::"
-          echo "::group::Perform doc test execution with coverage"
-          pytest --cov=petl petl
+          echo "::group::Perform doctest-modules execution with coverage"
+          pytest --doctest-modules --ignore-glob='*_py2.py'  --ignore-glob='petl/io/db.py' --cov=petl petl
           echo "::endgroup::"
 
       - name: Coveralls
@@ -154,7 +153,7 @@ jobs:
 
       - name: Install doc generation dependencies
         run: |
-          python -m pip install -r requirements-docs.txt
+          python -m pip install --prefer-binary -r requirements-docs.txt
 
       - name: Setup petl package
         run: python setup.py build
diff --git a/pytest.ini b/pytest.ini
index a8ca65f4..f9f044da 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -1,2 +1,3 @@
 [pytest]
 log_level=DEBUG
+doctest_optionflags = NORMALIZE_WHITESPACE ALLOW_UNICODE
diff --git a/requirements-formats.txt b/requirements-formats.txt
index 4480827d..767d87ea 100644
--- a/requirements-formats.txt
+++ b/requirements-formats.txt
@@ -5,6 +5,7 @@ intervaltree==3.0.2
 lxml==4.6.5
 openpyxl==2.6.2
 pandas<=1.1.2,>=0.24.2 ; python_version < '3.9'
+pandas ; python_version >= '3.9'
 tables
 Whoosh==2.7.4
 xlrd==2.0.1