What criteria defines infant colic?

The criteria that define infant colic is characterized by excessive crying, specifically the pattern of crying for more than three hours a day, occurring more than three days a week, and persisting for more than three weeks. This definition is used to help distinguish colic from other potential causes of excessive crying in infants.

The rationale behind this specific criterion is foundational to diagnosing colic. It establishes a clear framework that parents and clinicians can use to identify whether an infant's crying behavior falls within the defined parameters of colic, which is a common condition affecting infants, typically beginning at 2-3 weeks of age and resolving by 3-4 months. This definition emphasizes not just the frequency of crying, but also its duration and persistence, ensuring that the diagnosis is reserved for those cases that represent a significant and distressing pattern for both the infant and caregiver.

In comparison, the other options present varying durations and frequencies of crying that do not align with the standard definition used in clinical practice, which makes option A the accurate choice. The specified criteria in option A reflects the consensus in medical literature and guidelines, providing a reliable basis for diagnosis in pediatric practice.