In the fourth paragraph of the Letter to the Editor by Dr. Bruce D. Ackerman (Pediatrics 40:689, 1967) the second and third sentences should have read as follows:
"For the three separate studies of body chloride content, from which the authors calculated ECF, there is substantial agreement from one study to the next. Unfortunately, there is substantial disagreement from one study to the next among the four collected studies of chemically extractable fat."