Do you place endnotes (in vancouver reference style) after colons or before?
This is a relatively minor point, but in standard American English usage, footnote and endnote numbers would go after a punctuation mark, not before one. Usage in British English might be different, and individual publishers may have their own guidelines.

However, one might also ask why you aren't citing each item in the list separately; it might be more informative to the user rather than doing an all-purpose citation at the top of the list!