How processing fluency can design health messages and materials

While quality medical evidence underlies accurate health writing, clear writing helps the information translate easily – enter the concept of processing fluency.

A 2000 annual review in the US found patient resources and education materials are often written at a readability level that’s too high for most intended recipients.

But, it’s not just clear writing that helps or hinders our readers’ comprehension – how we present the information also influences audience interaction with online health information.

What is processing fluency?

Processing fluency is the ease with which readers process information.

It’s no secret that well-understood information generates a positive reader response.

When readers understand written health information, they have better comprehension and willingness to incorporate information into their existing lifestyle – for example, behaviour change, or maintaining existing healthy habits.

Processing fluency also impacts on readers’ ability to follow instructions of care, take medications, comprehend disease-related information and learn about disease prevention and health promotion.

Understanding processing fluency to design health materials

Earlier this year, researchers from Tokyo set out to explore the effects of processing fluency to help healthcare professionals better understand how to design health materials.

The research team searched for the keyword ‘processing fluency’ in several research databases.

Published in BMC Research Notes this year, the study found “fluent information” is:

pleasing
trustworthy
valuable
honest and sincere
safer

By defining the various perceptual, linguistic, retrieval and imagery effects of processing fluency, the researchers determined how best to create clear, effective health materials.

How to promote processing fluency

The researchers found there were six considerations to ensure readers have more processing fluency when reading health information.

1. Font

When designing health materials, the researchers found the recommended font size was considered 12 points or larger.

Both font style and colour were found to influence fluency for greater enjoyment of reading.

A good contrast between legible text and background colour increased positive judgments.

2. Plain language

The researchers found, “highly readable materials generate more favourable evaluations of the message.”

Common, familiar and simple words should be used instead of medical jargon to support processing fluency.

They also found choosing words that are easy to pronounce can have more favourable outcomes.

For example, the medication names that were easy to pronounce were perceived to be safer and have fewer side effects.

Short sentences also helped process information easily and quickly.

3. Fluent design

Variations in the contrast between the text and background improved processing fluency.

The researchers indicated highlighting key messages in the text using contrasting colours, such as blue or red, against the white background, made them more believable compared to low visibility statements.

4. Precise numeracy

Rounding numbers and limiting numbers to contain no more than two significant digits helped readers understand information.

Although in medical writing exact numbers are needed in some contexts for accuracy, the researchers suggest considering your audience and if numbers are used they should be clear and easy to understand.

Consider avoiding unnecessary overuse of numbers and explaining health risks using round numbers.

5. A limited number of key points

While it is common for written health materials to be information dense, patients and caregivers are often overwhelmed with too much information.

The researchers found minimising the cognitive load helps readers to retrieve and recall information, “prioritise what needs to be discussed and limit information to three to five key points.”