The width of the textbox used by survey item.
<textbox>
The value can be specified in percentages, pixels, or points.
The following displays the value of textboxwidth in a text stimulus:
<text sometext>
/ items= ("textboxwidth = <% textbox.q1.textboxwidth %>")
</text>
The following displays the value of textboxwidth in an instruction page:
<page somepage>
textboxwidth = <% textbox.q1.textboxwidth %>
</page>