How Point (Single-Probability) Tasks Are Affected by Probability Format, Part 2: A Making Numbers Meaningful...

Area of Science:

• Health Communication
• Risk Perception
• Behavioral Science

Background:

• The "Making Numbers Meaningful" review provides guidance on how data presentation formats impact health number comprehension.
• This article focuses on research examining "point tasks" where individuals extract information about single probabilities.

Purpose of the Study:

• To present evidence on how data presentation formats affect probability perceptions, feelings, health behaviors, trust, preferences, and discrimination outcomes.
• To synthesize findings from studies comparing different quantitative health information presentation formats for lay audiences.

Main Methods:

• Systematic review of experimental and quasi-experimental research comparing at least two data presentation formats.
• Inclusion of studies from multiple databases (MEDLINE, Embase, etc.) and hand searches.
• Extraction of data on stimulus (data format), task, and outcomes, reporting 466 findings from 161 articles.

Main Results:

• Moderate to strong evidence shows formats like "1 in X", icon arrays, bar charts, anecdotes, framing, and verbal probabilities influence probability perceptions and feelings.
• Only "1 in X" format, anecdotes, and framing demonstrated moderate to strong evidence in influencing health behaviors and intentions.
• Research on patient preferences for numerical, graphical, and verbal formats yielded only weak evidence.

Conclusions:

• The link between probability perception and health behavior is not strongly supported by current evidence, as many studies focus on short-term responses rather than long-term behaviors.
• Evidence on influencing health behaviors through number communication is weaker than evidence for influencing perceptions.
• Patient preferences for different numerical, graphical, and verbal probability formats lack strong evidence for stable and predictable patterns.