What is the subject-verb agreement for the phrase "A greater number of"?
I came across this sentence and am confused.
A greater number of cycles with paracetamol is associated with increased risk of ...
It could be either, depending on whether you're looking at 'one' greater number of things, or looking through it to the 'greater number' of them.
In your example, use is if the association is with the increased number of cycles (it's saying that since there are more cycles, risk has also increased). If you're saying that more of those cycles are associated with the increased risk - that is, the association is between the cycles and the risks, use are (it's saying that more of the cycles are associated with increased risk).
Most people would say are there so that the cycles are the risk, because normally a number of counts as a premodifier the same way a lot of or a great many does, and such things no more count for determining whether the verb should be singular or plural than the word some would.
I’ve prefixed each wrong word above with an asterisk.