Final answer:
The independent variable in this study is the amount of contact immediately after birth.
Step-by-step explanation:
The independent variable in this study is the amount of contact immediately after birth. The researcher operationalized physical contact by recording how often mothers touched or held their infants through the number of contact hours the mothers had with the babies immediately after birth. The researcher operationalized maternal behavior by varying the number of hours participants spent with their infants and measuring reluctancy to leave the infant, eye contact, and greater soothing behavior.