Which preference assessment involves placing items one at a time to see if the person engages with them?

The single-item approach is a preference assessment method where items are presented one at a time to the individual to observe their engagement with each item. This approach allows for a clear understanding of how much interest or preference the person shows towards each specific item, as it eliminates distractions that may occur when multiple items are available simultaneously. By focusing on one item, it becomes easier to assess the individual's reactions and preferences directly. This method is particularly useful for determining what might motivate or reinforce an individual, making it a valuable tool in behavior analysis.

In contrast, free-operant preference assessments allow individuals to freely interact with multiple items over a set period, giving a broader view of engagement but less precision with individual items. Paired-stimulus assessments involve presenting two items at a time to ascertain preferences between them, which can be informative but does not focus solely on individual item engagement. Multiple-stimulus assessments present a range of choices simultaneously and require the individual to select preferred items, which can lead to competitive dynamics that might interfere with understanding individual preferences.