Until an appropriate questionnaire is developed, we recommend the removal of confounding items and evaluation of a 10-item (2-factor) version of the questionnaire in a new tinnitus and perhaps nontinnitus population.
The system includes 27 items distributed among five subscales: reporting (ten items), external validity (three items), bias (seven items), confounding (six items), and power (one item).
Taken together, pilot data supports any differences in visuomotor distortion observed should not be confounded by item specifics.
We undertook a number of analyses to determine if it is likely to be a measure of actual personality style or is confounded by items capturing hypomanic/manic mood symptoms.
After eliminating 12 items confounded by medical illness, 11 items were selected using regression analysis, correlation with the total score, and factor analysis.
There was little commonality across the confounding items relating to the intervention, with almost one quarter of the studies (n = 10, 24%) reporting limitations relating to the delivery, duration or time of year for the educational intervention program.
This replicates findings from the oddball paradigm [24] [26] in a task where the participant is not required to judge the comparison stimulus against a large number of preceding items, and where the novelty of the item is not confounded with its position in the stimulus sequence.
Generic fatigue items might be confounded by disease specific conditions such as disability or disease activity [ 7].
Selecting inappropriate DIF methods by ignoring dual dependency will lead to costly decisions, such as removing item with negligible DIF from the test, or declaring group difference confounded by falsely identified DIF-present items.
Object presentation and visuomotor-flip condition was randomized within subjects, with each visuomotor condition having a 25% chance of occurring on any given trial, eliminating any confounds between item and visuomotor condition.
Thus, item information was not confounded with location information and planned saccades at any part of the task.
