the effectiveness of which

[alpacinou]

Hello.

Is this adjective clause I have used correct?

This measure, the effectiveness of which is debatable, is very costly.

 

[Yankee]

Yes.

 

[alpacinou]

Yes.

What area of grammar should I read to better understand that? Is it an adjective clause?

 

[alpacinou]

It is more specifically a non-defining relative clause.

Are relative clauses and adjective clauses the same thing?

How can you explain "of which"? What was the original sentence?