Yes, it needs to be blank otherwise people just don't bother completing it and it won't fail validation because it already has a date in it.
The HTML is...
<input type="text" class="form-control" name="DOB" id="datepicker_1" placeholder="Date of Birth" maxlength="10" value="<?php echo((ValidatedField("healthscreeningform_984","DOB")?ValidatedField("healthscreeningform_984","DOB"):date("d-m-Y"))); ?>" aria-describedby="basic-addon2" required>
Thank you.
NJ