It was devised by Dr Jeanne L. Ballard, professor emeritus of Pediatrics, Obstetrics and Gynecology at the University of Cincinnati College of Medicine.
The assessment assigns a score to various criteria, the sum of all of which is then extrapolated to the gestational age of the fetus.
The New Ballard Score is an extension of the above to include extremely pre-term babies, i.e., up to 20 weeks.
Whereas the neurological criteria depend mainly upon muscle tone, the physical ones rely on anatomical changes.
The neonate (less than 37 weeks of age) is in a state of physiological hypotonia.