balanced scale
a test or survey in which, for each possible response, there is a response that means the opposite. A rating scale with the four alternatives very poor, poor, good, and very good is an example, as is a set of survey questions in which half of the questions characterize a particular trait (e.g., perceived stress level) in one direction (e.g., low) and the other half characterize the trait in the opposite direction (e.g., high).