Which sentence is correct? a) While there is considerable attention given to business controls, we identified lack of audit trail related security controls implemented. b) While there is considerable attention given to business controls, we identified lack of implemented audit trail related security controls. Am not a native speaker. However, I prefer first option.
I would prefer the second one. The first one requires the reader to link the word "lack" to the word "implemented" over a span of six words. The second one require a link over a span of one word. In my mind, the key message here is the "lack of implementation." The rest of the words are qualifiers for that key message.
Stepping back just a bit, I would argue for some more direct language. For example:
The organization has given considerable attention to business controls. However, we noted the lack of an implemented audit trail related to security controls.