Hi, 

I am setting up an experiment which includes multiple tasks (stroop, backward digit, choice reaction etc) and three surveys. 

I have 32 participants split into two groups and each participant will carry out 1 each day. However to reduce the learning effect i need to create differences between the tests so i have Test A, B, C and D. I want to be able to give each participant a different experiment in a specific order as the weeks go by to be able to counterbalance (illustrated below). 

Is it therefore possible to counterbalance or offset <exp> through the webplatform and how do i do this in a specific order which changes each time they login? Does it need to relate to a participant identifier (like a group no.)? 

In addition i am currently producing each script separately (survey1, survey 2, survey 3, backward digit,etc) but i am struggling to combine <survey> with <htmlpage> for my preinstruction page is this not possible? I have seen that it is possible to change <surveys> to <block>, is there more detail on this?

Lastly in my survey i have a <page> of questions that i only want to appear if the last question on that page has a response of "Yes"? Is there an IF or Script Logic function available? 

Thankyou for your help. 

P.S. Fairly new to this so apologies for my terminology. 

You can use <batch> elements to administer the different versions / orders and assign participants to those orders using the groupnumber. You can pass this info to the launch page via a query parameter and give each participant a different link for each day, corresponding to the order / version they should complete on that day.

See e.g. https://www.millisecond.com/forums/FindPost12606.aspx for a simple example.

<survey> elements are special types of <block>s. To display your <htmlpage>, set up an <expt> in the script, use its /preinstructions to display the instructions and have it run the survey.

<expt>
/ preinstructions = (myhtmlpage)
/ blocks = [1=mysurvey]
...
</expt>

<survey mysurvey>
...
</survey>

<htmlpage myhtmlpage>
/ file = "myhtmlfile.htm"
</htmlpage>