In some situations, completing and faxing paper CRFs is still the best solution. Some of the reasons why this might be so include:
A well designed paper CRF is a creation of remarkable beauty and simplicity; light weight, no power or internet requirements, easy to navigate, and familiar to all. As a data capture tool it is very hard to beat.
When a paper form is used as the primary data capture tool, what could be simpler or faster than faxing it to it's destination.
If copies of source documents must be collected, faxing them will typically be more convenient than scanning them to a PC, and much faster than sending a photocopy by courier.
If a busy health care provider must choose between the practice of medicine and data entry, guess which task will be put on the back burner. In such cases you'll probably get the data quicker by fax than by EDC.
Not everyone is in love with computers, and some are downright hostile. If you want these individuals to participate in a research project it may be necessary to provide them with simple paper forms.
There are still places in the world where the information super highway just doesn't go.