looking for a brief test to demonstrate adequate english language comprehension to participate in a survey based research study; does anyone know of a validated tool or assessment that is not a significant time burden?
Are you talking about reading comprehension or oral comprehension? Either way, the most used tests of English proficiency in many language studies for children are subtests of the Woodcock-Johnson (WJIII). If your speakers are Spanish, there is a Spanish version called the Bateria (Woodcock/Munoz). I don't know what people use for adults. I don't know if it is normed for adults.
I just asked my friend and he said the Woodcock Johnson should work for people 2-90. I think you should get the WJ and pick the subtests that would help you.
Perhaps worth looking at the C-test? Here's a link to an article about C-testing, including useful references: https://pooya.um.ac.ir/ResearchDocuments/papers/1007771.pdf