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Decision aids improve knowledge and involvement in people making treatment or screening decisions

Stacey D, Legate F, Col NF, et al. Decision aids for people facing health treatment or screening decisions. Cochrane Database Sys Rev. 2014;1:CD001431.

Review question

Do decision aids help people make decisions about treatment or screening related to their health?


Often, people need to make decisions about their healthcare where there is no clear best choice among options or there may be both benefits and harms that need to be considered. Decision aids provide information to help people to take an active role in making informed decisions about their healthcare options with the help of their healthcare providers.

How the review was done

The researchers did a systematic review, searching for published studies of decision aids up to June 2012. They found 115 randomized controlled trials of 34,444 patients from 9 countries.

In the trials, people were making decisions for themselves, for a child, or for a family member who could not help with decision-making.

Decision aids were tools to help people choose among treatment or screening options by

  • making clear what decision needed to be made;
  • giving information on the options and their potential benefits or harms; and
  • identifying what was important to the person making the decision.

Types of decision aids included pamphlets, videos and computer-based tools.

Most trials compared decision aids plus usual care with usual care alone.

What the researchers found

The quality of evidence was rated as medium to high for most trials.

Compared with usual care, decision aids:

  • increased knowledge about the different options;
  • reduced feeling uninformed;
  • reduced feeling unclear about personal values;
  • increased the number of people who were involved in decision-making; and
  • increased the number of people who accurately understood the risks of each of the options.


In people who have to make a decision about treatment or screening related to their health, decision aids improve knowledge about different options and involvement in decision-making. They also reduce the number of people who feel uninformed or unclear about their options.

Decision aids versus usual care for making treatment or screening decisions


Number of trials and people

Abolute effect of using decision aids

Quality of evidence

Knowledge about options

42 trials (10,842 people)

Knowledge improved by about 13 points out of 100


Decisional conflict (feeling uninformed)

22 trials (4,343 people)

People felt more informed by about 7 points out of 100


Decisional conflict (feeling unclear about personal values)

18 trials (3,704 people)

People felt clearer about their values by about 6 points out of 100


Participation in decision making

14 trials (3,234 people)

7 more people out of 100 were involved in decision-making


Understanding the risks of each of the options

19 trials (5,868 people)

24 more people out of 100 understood the risks




Randomized controlled trials
Studies where people are assigned to one of the treatments purely by chance.
Systematic review
A comprehensive evaluation of the available research evidence on a particular topic.

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