The Balanced Incomplete Design is a design that has an equal number of observations but not all treatments can be assigned to each block, set or session. This can be used to create a design that contains more products than product presentations. For example you have 5 products but only want to present 3 products to each panellist. Keep in mind to always specify a number of treatments that is less than the number of products.

Within EyeQuestion, by using the design generator it is currently not possible to generate a Balanced Incomplete design containing more than 17 products. However it is possible to create it by following the steps below:

Create a balanced design including all products you want to evaluate (e.g. 40 products). Define in this step if the design should be monadic sequential or block design by selecting this option under "Multi Product". Click Generate Design.

Export your design by clicking to Design>Files to Import Design>Excel .

Step 3. 
Open the Excel file and remove the columns of the samples you do not want to include. For example, if you want the panelists to evaluate only 20 out of the 40 products, delete the columns for samples from 21 onwards.

Go back in EyeQuestion and click Design>Import Design and select the excel file you just created.

Once the design is imported you will obtain the correct balanced incomplete design.