Error in questionnaire data / reported values

Error in questionnaire data / reported values

by Björn Fisseler -
Number of replies: 2

Hello,

we are using the Questionnaire activity to collect data from students. Several questions are 5-point rating scales, possible answers range from 1-5. So the number of possible answers are implemented as named degrees, ranging form 1-5:

named degrees ranging from 1 to 5

The first error appears in the answer report:

table of reported values

The percentage is calculated based on the absolute frequency and should sum up to 100%, which it won't in this example (1+6+19+23+23 = 72). Where are the missing 28%?

The answer can be found when downloading the raw data. The results suddenly range from 1-7 plus -999 for missing values:

calculated values

Where do the values 6 and 7 come from? They were not specified inside the question? The frequencies sum up to the missing 28% (468 + 190 = 658; 658 / 2295 * 100 = 28%).

What is going on here and how can we ensure the questionnaire collects valid data?

For completeness:

  • Moodle is 3.11.5 (Build: 20220117)
  • Questionnaire plugin is 3.10.1 (Build - 2021080400)

Any suggestions are highly appreciated!


Average of ratings: -
In reply to Björn Fisseler

Re: Error in questionnaire data / reported values

by AL Rachels -
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I am not certain, but I think the data for that type of question is in the mdl_questionnaire_response_rank table of your database. It would be interesting to see what is in the rankvalue fields where the question_id matches the question you are specifying.
In reply to AL Rachels

Re: Error in questionnaire data / reported values

by Björn Fisseler -

Thanks, I took a look at the database table, but I'm not sure whether I understand the relations correctly:

  • questionnaire: lists all the questionnaires
  • questionnaire_question: lists questions per survey; found the correct surveyid and the relevant "id" for the question (id: 716 in this case)
  • questionnaire_response_rank: "question_id" should match the "id" from the "questionnaire_question"-table, but there are no responses stored for "question_id = 716"
Where can I find the correct question_id for the relevant question?