app/views/shared/histories/_investigated_change.html.erb
<% if to_value == 'true' || to_value == true %>
<%= datetime %> <%= t("histories.investigated.mark_as_investigated_by") %> <%= user_name %> <%= t("histories.belong_to") %> <%= organisation %> <%= t("histories.because") %> <%= message %>
<% else %>
<%= datetime %> <%= t("histories.investigated.mark_as_not_investigated_by") %> <%= user_name %> <%= t("histories.belong_to") %> <%= organisation %> <%= t("histories.because") %> <%= message %>
<% end %>