## Table 2 |
||||||

Questionnaire items, correct response rate, and factor loading for each item for Schwartz-J
and LipkusJ |
||||||

Question |
Answered correctly^{a} |
Schwartz-J^{c} |
Lipkus-J^{d} |
|||

Factor loading^{b} |
Communality (h^{2}) |
Factor loading^{b} |
Communality (h^{2}) |
|||

1 Imagine that we rolled a fair, six-sided die 1,000 times. Out of 1,000 rolls,how many times do you think the die would come up even (2, 4, or 6)? | 85(55) | 0.66 |
0.43 | 0.68 |
0.46 | |

2 *In a lottery, the chance of winning a 1,000 yen prize is 1%.What is your best guess about how many people would win a 1,000 yen prize if 1,000 people each buy a single ticket to this lottery? | 82(60) | 0.74 |
0.55 | 0.63 |
0.40 | |

3 *In a lottery, the chance of winning a car is 1 in 1,000. What percent of tickets to this lottery win a car? | 73(21) | 0.66 |
0.43 | 0.61 |
0.37 | |

4 Which of the following numbers represents the biggest risk of getting a disease? 1 in 100, 1 in 1000, 1 in 10 | 95(78) | 0.90 |
0.81 | |||

5 Which of the following numbers represents the biggest risk of getting a disease? 1%, 10%, 5% | 97(84) | 0.82 |
0.67 | |||

6 If Person A’s risk of getting a disease is 1% in ten years, and person B’s risk is double that of A’s, what is B’s risk? | 92(91) | 0.78 |
0.61 | |||

7 If Person A’s chance of getting a disease is 1 in 100 in ten years, and person B’s risk is double that of A’s, what is B’s risk? | 90(87) | 0.71 |
0.50 | |||

8 If the chance of getting a disease is 10%, how many people would be expected toget the disease:A: Out of 100? | 92(81) | |||||

9 If the chance of getting a disease is 10%, how many people would be expected toget the disease:B: Out of 1000? | 91(78) | 0.77 |
0.60 | |||

10 If the chance of getting a disease is 20 out of 100, this would be the same as having a ____% chance of getting the disease. | 93(70) | 0.77 |
0.59 | |||

11 The chance of getting a viral infection is .0005. Out of 10,000 people, about how many of them are expected to get infected? | 69(49) | 0.18 | 0.03 |

^{a}Percentage of participants who responded correctly to each item. Corresponding values
on the original American study are shown in parentheses ([15], n = 463).

^{b}Factor loadings are shown as pattern matrix.

^{c}For Schwartz-J, one factor consisting of all three items accounted for 47.1% of variance.

^{d}For Lipkus-J, one factor consisting of 9 items accounted for 55.6% of variance.

*Slightly modified from the original for the Japanese context.

Okamoto * et al.*

Okamoto * et al.* *BMC Medical Informatics and Decision Making* 2012 **12**:104 doi:10.1186/1472-6947-12-104