A reassessment of US public birth records aims to create an updated data set for physicians to use when determining a baby's size relative to other newborns.

Michigan State University biostatistics professor Nicole Talge and her collaborators reviewed more than 7 million US birth records in a one-year period and compiled the data to get a more accurate and up-to-date assessment of newborn size.

"Our research looked at live births in the United States during 2009-2010 and using a newly developed method, corrected unlikely gestational ages during that time. This led to changes in the birth weight thresholds, especially for preterm and post-term babies," Talge said is a news release from MSU.

Having accurate data when establishing birth weight thresholds is important, Talge said, because these data are what physicians use to determine whether a baby is large or small for its gestational age.

The new data set, which Talge and her colleagues reported in the journal Pediatrics, helped introduce an updated and potentially more precise way to evaluate a baby's birth size, MSU reported.

Since birth size is often used as a measure of a baby's health, the new thresholds will be useful for health care providers, the researchers said.

Part of the revised calculation included a comparison of the last menstrual cycle of the mother and the estimated gestational age of the fetus against the actual birth weight of the baby when it's born. Doing this allowed the research team to identify birth records that were likely to have errors.

Doctors investigating a patient's health later in life may also find use in the updated records, the researchers said.