Harrington (2013) examined relationships among physical activities, weight, and sleep duration (measured in minutes per night) in a sample of 8-year-old children. What inferential statistical technique did Harrington conduct in analyzing her study data? Provide a rationale for your answer.

Source: Harrington, S. A. (2013). Relationships of objectively measured physical activity and sleep with BMI and academic outcomes in 8-year-old children. Applied Nursing Research, 26(2), 63-70.