Decisive analysis of titles must be arranged (6,4)

I believe the answer is:

litmus test

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'decisive analysis of titles must be arranged' is the definition.
I can't tell whether this defines the answer.

'titles must be arranged' is the wordplay.
'be arranged' is an anagram indicator.
'titles'+'must'='titlesmust'
'titlesmust' with letters rearranged gives 'LITMUS TEST'.

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(Other definitions for litmus test that I've seen before include "Chemical trial" , "Observer may see red after one" .)

I've seen this clue in The Irish Times.

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