Is this query correct and optimize?

Transact-SQL
1 

		update mkf set mkf.Score= mkf.score -
		(
		select sum(pp.ScoreInScale) from Progresses pp 
		where pp.MemberKnowledgeFieldId = mkf.Id
		and pp.KnowledgeId in
			(select k.KnowledgeId  from knowledges k where k.Code in 
				(
				8396
				,8395
				,7999
				,7723
				,7751
				,7753
				,8069
				,362
				,7733
				,7993
				,8379
				,7736
				)
			)
		)
		  FROM NewKms_MECO..MemberKnowledgeFields mkf
		  where mkf.Id in 
		  (select p.MemberKnowledgeFieldId from Progresses p 
			  where p.KnowledgeId in 
			   (
					select k.KnowledgeId  from knowledges k where k.Code in 
					(
					8396
					,8395
					,7999
					,7723
					,7751
					,7753
					,8069
					,362
					,7733
					,7993
					,8379
					,7736
					)
			   )
		  )
2

We can't judge whether or not is correct without knowing what it is intended to do.

I can say it is a complete mess as far as readability and maintainability is concerned.

As far as optimized, all I can do is judge it by intuition since I know almost nothing about the tables and indexes, and the impression I get is that it is not optimized.