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Your LimeSurvey version: [see right hand bottom of your LimeSurvey admin screen] LimeSurvey Community Edition (CE) v.  5.4.0+220913
Own server or LimeSurvey hosting: I am not sure. My organization gave me the admin account. 
Survey theme/template: two rounds of Delphi survey 
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 Hello. I'm a master's student at the University of Alberta here on Canada. My team plans to do an online Delphi survey, two rounds, using LimeSurvey Community Edition. I want to ask what plugin I should use and how to add it. In the first round, respondents will be asked to rate a list of statements and the option to write comments. In the second round, respondents will need to see their responses from round 1 and the aggregate response of respondents. Any recommendation to do so? 

Will appreciate your response. 
Marlo 

I don't think that there is a plugin to do this for you.

I assume you know the respondents and thus you will use a token based survey, correct?

So after the first round, you will have to extend your participants table with some custom attributes, for at least their responses. The aggregate responses you could already include directly into the survey, as they will be the same for everyone.

But their specific answers you will need to save into custom attributes in the participant / token table and then pipe them into the survey via expressions script, something like this {TOKEN:ATTRIBUTE_1}.

Hello Holch. Thanks for the response! I just met my team this afternoon and talked about your insights. Yes, we know our respondents and will be using token.

I'll try to find a thread or in the manual on extending the participants' table and how to pipe. Is there a thread about it that you can recommend? I'm still navigating Lime and playing around with it.

extending the participants' table

[url] www.limesurvey.org/manual/Survey_partici...en#Manage_attributes [/url]

how to pipe

As @holch: {TOKEN:ATTRIBUTE_1}, {TOKEN:ATTRIBUTE_2},...,{TOKEN:ATTRIBUTE_73}
It's always the same procedure, if you pipe answers of a previous questions or content of a token (like "firstname") or an additional attribute of the token.
[url] www.limesurvey.org/manual/ExpressionScri..._a_previous_question [/url]