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How should risk be communicated to children: a cross-sectional study comparing different formats of probability information.

Ulph F, Townsend E, Glazebrook C - BMC Med Inform Decis Mak (2009)

Bottom Line: The ability to understand carrier results relies on an understanding of probabilistic terms.Research with adult populations suggests information format significantly affects comprehension.This study aimed to explore which presentation format is most effective in conveying probabilistic information to children.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Psychological Sciences, University of Manchester, Oxford Road, Manchester, UK. fiona.ulph@manchester.ac.uk

ABSTRACT

Background: Newborn screening, which identifies inherited disorders and sometimes carrier status, will increasingly involve health professionals in the provision of appropriate information and support to children and their families. The ability to understand carrier results relies on an understanding of probabilistic terms. However, little is known about how best to convey probabilistic medical information to children. Research with adult populations suggests information format significantly affects comprehension. This study aimed to explore which presentation format is most effective in conveying probabilistic information to children.

Methods: A probabilistic task based on the cup game was used to measure which of five different formats was associated with greatest understanding in children aged 7-11 years old (n = 106). Formats used were verbal labels (e.g. rarely, sometimes), percentages, proportion-word (e.g. 1 in X), proportion-notation (e.g. 1:X) and pie charts. There was also an additional mixed format condition. In each trial a picture was presented of three cups, each with a different probability depicted beneath it, and the child was asked to select which cup was most likely to contain the ball. Three trials were presented per format. Children also rated how certain they were that they had answered correctly.

Results: There was a significant relationship between format and comprehension scores. Post hoc tests showed children performed significantly better when probability was presented as a pie chart, in comparison to percentages, proportion-notation, proportion-word and mixed format trials. Furthermore, most children (84%) got all trials correct for this format and children were significantly more certain that their response was correct in the pie chart trials compared to all the other formats (p < 0.001). Significant positive correlations were found between self-ratings of certainty and comprehension of verbal labels, percentages and pie charts. Older age was also associated with better performance on all formats except percentages. Overall comprehension was calculated by summing the scores for the individual trials and this was independently associated with older age and higher IQ.

Conclusion: The results suggest that 7-11 year olds can understand probability information, but that the format used will significantly affect the accuracy and confidence with which children in this age group make judgements about the likelihood of an event. Of the formats studied, pie charts appear to be the optimal method of presenting probabilistic information to children in this age group. Health professionals and designers of health messages should be cognisant of this when communicating medical information to children aged 7-11 years old.

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Related in: MedlinePlus

Mean cup game score and 95% confidence intervals per format for entire sample.
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Figure 4: Mean cup game score and 95% confidence intervals per format for entire sample.

Mentions: For each trial children could score 1 point for selecting the correct cup, creating a maximum score of 3 per format. The mean correct scores per format are presented in Figure 4 with error bars representing 95% confidence intervals. The graph illustrates that children achieved the highest scores with pie charts, followed by verbal labels and percentages.


How should risk be communicated to children: a cross-sectional study comparing different formats of probability information.

Ulph F, Townsend E, Glazebrook C - BMC Med Inform Decis Mak (2009)

Mean cup game score and 95% confidence intervals per format for entire sample.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2698821&req=5

Figure 4: Mean cup game score and 95% confidence intervals per format for entire sample.
Mentions: For each trial children could score 1 point for selecting the correct cup, creating a maximum score of 3 per format. The mean correct scores per format are presented in Figure 4 with error bars representing 95% confidence intervals. The graph illustrates that children achieved the highest scores with pie charts, followed by verbal labels and percentages.

Bottom Line: The ability to understand carrier results relies on an understanding of probabilistic terms.Research with adult populations suggests information format significantly affects comprehension.This study aimed to explore which presentation format is most effective in conveying probabilistic information to children.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Psychological Sciences, University of Manchester, Oxford Road, Manchester, UK. fiona.ulph@manchester.ac.uk

ABSTRACT

Background: Newborn screening, which identifies inherited disorders and sometimes carrier status, will increasingly involve health professionals in the provision of appropriate information and support to children and their families. The ability to understand carrier results relies on an understanding of probabilistic terms. However, little is known about how best to convey probabilistic medical information to children. Research with adult populations suggests information format significantly affects comprehension. This study aimed to explore which presentation format is most effective in conveying probabilistic information to children.

Methods: A probabilistic task based on the cup game was used to measure which of five different formats was associated with greatest understanding in children aged 7-11 years old (n = 106). Formats used were verbal labels (e.g. rarely, sometimes), percentages, proportion-word (e.g. 1 in X), proportion-notation (e.g. 1:X) and pie charts. There was also an additional mixed format condition. In each trial a picture was presented of three cups, each with a different probability depicted beneath it, and the child was asked to select which cup was most likely to contain the ball. Three trials were presented per format. Children also rated how certain they were that they had answered correctly.

Results: There was a significant relationship between format and comprehension scores. Post hoc tests showed children performed significantly better when probability was presented as a pie chart, in comparison to percentages, proportion-notation, proportion-word and mixed format trials. Furthermore, most children (84%) got all trials correct for this format and children were significantly more certain that their response was correct in the pie chart trials compared to all the other formats (p < 0.001). Significant positive correlations were found between self-ratings of certainty and comprehension of verbal labels, percentages and pie charts. Older age was also associated with better performance on all formats except percentages. Overall comprehension was calculated by summing the scores for the individual trials and this was independently associated with older age and higher IQ.

Conclusion: The results suggest that 7-11 year olds can understand probability information, but that the format used will significantly affect the accuracy and confidence with which children in this age group make judgements about the likelihood of an event. Of the formats studied, pie charts appear to be the optimal method of presenting probabilistic information to children in this age group. Health professionals and designers of health messages should be cognisant of this when communicating medical information to children aged 7-11 years old.

Show MeSH
Related in: MedlinePlus