Only this past week we had a form owner asks us to change the design of a new form and put the boxes to the left of the caption text.
Here are two examples of where to place the ballot boxes and text.
The second example above shows the value in a questionnaire form where there is follow-on information after the box is checked. Again, this is because the form filler reads from left to right.
Exceptions do occur.
The main exception to the above is where a form has its data preprinted and the ballot box is there solely for the use of the person READING then form since it is a machine that enters the data. In this case it would be logical to palce the box before the caption since that's the reading order.
It really gets down to whether you consider ease of use for the form filler has priority.
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