Table 1.

Surveillance data matching algorithm.

Match level	Match criteria
Match 1	If social security number
Match 2	Else if, first name (first 6 letters), last name, date of birth
Match 3	Else if, last name (first letter), last name (letters 3 through 8), first name (letters 2 through 8), date of birth
Match 4	Else if, last name (first letter), last name (letters 3 through 8), first name (letters 2 through 8), birth month, birth year
Match 5	Else if, last name (first letter), last name (letters 3 through 8), first name (letters 2 through 8), birth day, birth year
Match 6	Else if, last name, first name (letters 1 through 2), date of birth
Match 7	Else if, last name (letters 1 through 3), first name (letters 1 through 3), date of birth
Match 8	Else if, last name (letters 1 through 4), first name (letters 1 through 4), birth year
Match 9	Else if, first name (letters 1 through 3), last name (letters 1 through 3), birth month, birth year
Match 10	Else if, first name (letters 1 through 3), last name (letters 1 through 3), birth day, birth year
Match 11	First name (letters 1 through 3), last name (letters 1 through 3), birth month, birth year