The third section compares the statistical characteristics of the mixed option version against the fixed option versions of the test.
Using a group of 1000 Israeli subjects they found that the 2-option version of the test was easiest and least reliable with the difficulty of the formats increasing with the number of options, and concluded that the optimum number of options was greater than three.
In this case, the three-option version of the item is of acceptable quality and need not be further modified.
The development of the full, 5-option version of the decision aid has been described previously [ 3].
However, you do have the option to view an alternative version of the feed if you would prefer.
They found significant differences in difficulty between 3- and 4-, and between 3- and 5-option versions of the three tests adapted to produce the different option versions, but found no differences between the 4- and 5-option versions.
A comparison of scores, facility, discrimination, reliability and validity from 3-, 4- and 5-option versions of the multiple choice test found little variation in the performance of the three option formats although higher numbers of options tended to increase difficulty and to spread responses between the options.
They also found no significant differences in the discrimination coefficients of the different option versions, but for two of the three tests used they found the 3-option version to be significantly more reliable than the 4-option version, while for the third test they found the 5-option test to be more reliable than the 4-option test.
For those who viewed the 2-option version, 68% of participants selected colonoscopy without out-of-pocket costs, but only 41% selected colonoscopy when out-of-pocket costs were added.
Test choice appeared to differ modestly (although the difference did not reach statistical significance) between the 5-option and 2-option version when no out-of-pocket costs were assumed.
His strategy is bound to open a prolonged period of uncertainty in which events could put his preferred option — a looser version of full British membership — out of reach.
