Highlights
fits
GIST
People differ systematically in whether they understand graphical or numerical representations of statistical information better. However, assessing these underlying skills to get the right representation to the right people is not feasible in practice. A simple and efficient method to achieve this could be to let people choose among representations themselves.However, our study showed that allowing participants to choose a representation (numerical v. graphical) did not improve overall or gist knowledge compared with determining the representation randomly, even though it did slightly improve verbatim knowledge.Rather, participants largely chose the representation they found more attractive. Most preferred the graphical representation, including those with low graph literacy.It would therefore be important to develop graphical representations that are not only attractive but also comprehensible even for people with low graph literacy.Making informed health decisions requires understanding of basic statistical information about the benefits and side effects of medical treatments and other health-relevant behaviors. It is well documented, however, that understanding statistical information is quite challenging for most people, including for experts.However, while the use of graphical representations is often recommended as an aid for the interpretation of numerical data,The question thus arises how to get the right representation to the right person, that is, a representation (numerical or graphical) that this person understands well. Assessing patients’ graph literacy and numeracy prior to presenting medical information is time-consuming and potentially awkward, so that it is often not feasible in practice. A much simpler and more feasible method consists in letting people choose which representation they would like to receive themselves, rather than deciding it for them. To improve knowledge, this method would require that people are able to identify the representation that they comprehend better, that is, the representation that fits to their graph literacy and numeracy skills. In this study, we therefore investigate whether allowing people to choose a representation of statistical information does indeed improve knowledge and increases the fit to the underlying skills, compared with a situation in which the representation is randomly assigned.To investigate this question, we conducted an experiment in which participants received statistical information about the benefits and side effects of a painkiller medication. The central manipulation was that half of the participants could choose whether they wanted a graphical or a numerical representation of that information, whereas the other half of the participants received 1 of the 2 representations at random. At 2 time points of measurement, we assessed how well they comprehended (T1) and recalled (T2) the statistical information that they received. The 2 time points were primarily used to enhance the sensitivity to detect differences by avoiding potential ceiling effects and to check potential effects for robustness. In line with previous research (e.g., Gaissmaier et al.,Three research questions guided us, which will be described in detail subsequently: 1) Which representation will be chosen predominantly, and who chooses the graphical rather than the numerical representation? 2) Does being able to choose between numerical and graphical representations foster knowledge of statistical information in comparison with random allocation to either graphical or numerical representations? 3) Does choice increase ratings of accessibility and/or attractiveness, suggesting that either of those attributes may play a role in choosing?