Which statement best describes ABBA pattern?

Which statement best describes ABBA pattern?

• A. It balances order effects by assigning different orders to groups
• B. It uses a single fixed order
• C. It eliminates the need for a control
• D. It randomizes the order within each trial

Answer: (A)

ABBA pattern targets order effects in experiments where participants experience more than one condition. By assigning different sequences to groups, it distributes any carryover, practice, or fatigue effects across conditions rather than letting them bias a particular condition. In practice, some participants might experience the conditions in one sequence (for example, first condition, then second, then second, then first) while other participants experience the opposite sequence. This spread keeps the impact of order effects balanced, so differences between conditions reflect true effects rather than the order in which tasks were completed. This is why it’s not about a single fixed order (that would risk systematic bias), not about eliminating a separate control condition, and not about randomizing order within each trial. ABBA specifically uses planned, alternating sequences to counterbalance order effects.

ABBA pattern targets order effects in experiments where participants experience more than one condition. By assigning different sequences to groups, it distributes any carryover, practice, or fatigue effects across conditions rather than letting them bias a particular condition.

In practice, some participants might experience the conditions in one sequence (for example, first condition, then second, then second, then first) while other participants experience the opposite sequence. This spread keeps the impact of order effects balanced, so differences between conditions reflect true effects rather than the order in which tasks were completed.

This is why it’s not about a single fixed order (that would risk systematic bias), not about eliminating a separate control condition, and not about randomizing order within each trial. ABBA specifically uses planned, alternating sequences to counterbalance order effects.