Dear all:

I hate bad science.  I have now tracked down the error that the neonatologists made in 
their conclusion that "test-weighing is imprecise".  In actuality, the precision of the 
differences between estimates of observed volume, before and after a baby feeds from 
the bottle are abysmal.

The range of my small study was +8/-13 g for the SAME BOTTLE observed 4 times before 
(two observers, two estimates each) and four times after the feeding.  The interquartile 
range was + 5/-2 g.  

In contrast, the interquartile range for imprecision of test-weighing bottles and test-
weighing babies was +/- 0 g.  That's right ZERO! A big fat dot right in the middle.  Didn't 
matter if you weighed the baby or the bottle - it was ZERO.  And this was with a whole 
bunch of different mothers, many of whom were sleep deprived.

I have to say that I am sometimes shocked at how we can be blinded by our frame of 
reference.  Every single person that I talked to, including an epidemiologist who helped 
with a few correlation stats, assumed that observed volume is the reference.

My conclusion, observed volumes of what an infant takes from a bottle should NEVER be 
used to determine an infant's intake.  It is highly imprecise and no indication of how an 
infant feeds normally from the breast.

Regardless of where you stand on test-weighing -- I would NEVER use observed volume 
of the intake from a bottle as anything but a rough guide that the baby drank SOMETHING 
from a bottle within a half ounce or 15 ml range.

Best, Susan

             ***********************************************

Archives: http://community.lsoft.com/archives/LACTNET.html
Mail all commands to [log in to unmask]
To temporarily stop your subscription: set lactnet nomail
To start it again: set lactnet mail (or [log in to unmask])
To unsubscribe: unsubscribe lactnet or ([log in to unmask])
To reach list owners: [log in to unmask]