Our hospital lab has adopted TSH reflex testing in which if TSH is in acceptable range no further testing will be done. Wanted to hear thoughts from esteemed informed colleagues In pitfalls of such approach. 
thank you 

Hi @Rao , do you mean as a test for congenital hypothyroidism? 

as a test to r/o hypothyroid ( in premature infants or in term infants in the first many days of life). Reflex TSH testing appears becoming the standard order for testing Thyroid status in infants beyond neonatal period to adulthood

3 minutes ago, Rao said:

LaFranchi SH (2021) Thyroid Function in Preterm/Low Birth Weight Infants:Impact on Diagnosis and Management of Thyroid Dysfunction.Front. Endocrinol. 12:666207.
doi: 10.3389/fendo.2021.666207

trying to see If the test- Reflex T4 adequately addresses the issue  based on this 

On 6/25/2023 at 6:37 AM, Rao said:

as a test to r/o hypothyroid ( in premature infants or in term infants in the first many days of life). Reflex TSH testing appears becoming the standard order for testing Thyroid status in infants beyond neonatal period to adulthood

trying to see If the test- Reflex T4 adequately addresses the issue  based on this 

why the term reflex mentioned instead screening- please clarify 

Hi. The determination of FT4 in very premature and extremely premature newborns is standard care in national neonatal units and worldwide, however there is controversy about what levels are considered normal in this group of newborns.

Thyroid function may be affected in newborns with hyaline membrane disease or respiratory distress and are associated with euthyroid sick syndrome. 
Newborns ≤ 32 weeks or very low weight <1,500g are a group of patients at risk of presenting thyroid dysfunction. Normal TSH concentrations in the screening test during the first days of life in premature infants do not rule out the presence of CH.

Given the risk of false negatives in CH screening and the probability of thyroid dysfunction, it is suggested to repeat the analytical determination at 2 weeks of life, 4 weeks, when it reaches 1,500 g or at discharge.

https://www.analesdepediatria.org/index.php?p=revista&tipo=pdf-simple&pii=S1695403321001727

https://www.scielo.cl/pdf/rcp/v89n2/0370-4106-rcp-89-02-00202.pdf