Karen becomes pregnant during her sophomore year in high school. After she has the baby, Karen has to manage the stress of finding childcare for her son during school hours. Which element of the Double ABCX Model does the stress of childcare represent?

The stress of childcare represents the A variable in the Double ABCX Model.

The ABCX Formula was theorized in the 1950s by Reuben Hill as a stress or crisis-proneness model in family contexts. The formula describes variables which can lead to crises:

A is the event or element triggering the crisis, B is the family's resources to deal with the crisis, C is how the family defines or interprets the event, X is the crisis.

This model is often considered flawed because of how inflexible and linear it is. This is why it was expanded upon by Hamilton McCubbin and Joan Patterson during the Vietnam War, when family structures were affected by the absence of a father. McCubbin and Patterson introduced additional elements to the A, B and C components, as well as family coping mechanisms, thus creating the Double ABCX Model.

In this updated model the basic variables are the same, albeit revised. But the A variable still consists of the initial life stressor (s), which corresponds to the strain represented by the need to find chilcare for Karen's baby.