Regarding diagnostic tests for syphilis, true is all except
For population screening for syphilis, VDRL or RPR test is appropriate.
VDRL test is used for measurement of antibody titers to assess response to treatment.
FTA-ABS is used to confirm diagnosis in clinically suspected syphilis.
TP-PA test is appropriate for population screening for syphilis.
Fourfold decrease in titer is required by 6 months after therapy for primary syphilis.