hi...I'm trying to validate phone number (correct format), name (only letters and minimun 2 letter) and DOB (Correct format, no letters). What I have so far only returns false in the user leaves the field "Empty". Any help would be greatly appreciated, thx!:

<script type="text/javascript">

<!--

function validate_form ( )
{
valid = true;

if ( document.schedule.firstname.value == "" )
{
alert ( "Please fill in your 'First Name'" );
valid = false;
}

else if ( document.schedule.lastname.value == "" )
{
alert ( "Please fill in your 'Last Name'" );
document.schedule.lastname.focus();
valid = false;
}

else if ( document.schedule.phone.value == "" )
{
alert ( "Please fill in your 'Phone Number' and remember to include your area code" );
document.schedule.phone.focus();
valid = false;
}

else if ( document.schedule.phone2.value == "" )
{
alert ( "Please fill in your 'Phone Number' and remember to include your area code" );
document.schedule.phone2.focus();
valid = false;
}

else if ( document.schedule.phone3.value == "" )
{
alert ( "Please fill in your 'Phone Number' and remember to include your area code" );
document.schedule.phone3.focus();
valid = false;
}

else if ( document.schedule.dob.value == "" )
{
alert ( "Please fill in your 'Date of Birth'. Your birth date must be in the past." );
document.schedule.dob.focus();
valid = false;
}

else if ( ( document.schedule.referral[0].checked == false ) && ( document.schedule.referral[1].checked == false ) )
{
alert ( "Do you have a referral from your doctor?" );
valid = false;
}

else if ( ( document.schedule.hmo[0].checked == false ) && ( document.schedule.hmo[1].checked == false ) )
{
alert ( "Is your insurance in an Health Maintenance Organization (HMO)?" );
valid = false;
}

else if ( ( document.schedule.hmo[0].checked == false ) && ( document.schedule.hmo[1].checked == true ) )
{
alert ( "HMO Insurance plans require an authorization. Please contact your MD to obtain this, and come back to our website to request your appointment." );
valid = false;
}


return valid;
}

//-->

</script>