Is it necessary to have a confirmatory test if found positive in g6pd newborn screening?

Usually not... If a baby is found to have g6pd deficiency on newborn screening, it usually means that the infant actually has it. The test can be falsely negative in certain circumstances, but a positive test is usually accurate. That being said, different states use different tests. I would 1st talk with your pediatrician about this, then they may refer you to hematologist to get guidance on living with g6pd.