Hello, I have 15 vignettes that participants will rate on a scale of one to 10. Each vignette is a block. I want the 15 vignettes to be randomly assigned to three accountability conditions (five vignettes per condition). Each condition is a block which is also randomised so all participants are exposed to all three conditions just in a different order.
Randomising the three conditions works fine – I randomise for all three conditions to be shown. However, I am not sure how to treat the vignettes. Currently I have all 15 blocks randomised under each condition block but this means I am getting duplicates across conditions because each set is randomly selected from the total group of 15 vignettes each time. I want each vignette to appear only once across all three conditions – randomisation but without repeats.  Is there a way to do this?
I also want to make sure I collect all data about the order and condition for each vignette per participant – so any tips on making sure I get this right would be a big help. Thanks in advance for any help you can offer.