Which statement correctly compares compression depths for child and infant CPR?

• A. Child: at least one third AP diameter of chest (about 2 inches); Infant: at least one third AP diameter (about 1.5 inches)
• B. Child: at least 2 inches; Infant: about 1 inch
• C. Child: about 1 inch; Infant: about 3 inches
• D. Child: at least one third AP diameter; Infant: about 2 inches

Answer: (A)

In pediatric CPR, chest compression depth should be proportional to chest size: at least one third of the chest’s front-to-back diameter. For a typical child, that works out to about 2 inches, and for an infant, about 1.5 inches. So the statement that a child should have a depth of at least one third of the chest (roughly 2 inches) and an infant at least one third of the chest (roughly 1.5 inches) matches the guidelines exactly. The other options give depths that are too deep for infants or too shallow, or mix up the proportional depth, which is why they aren’t correct.