I am writing in British English so do not use a comma before 'and' in a list.
E.g The basket had oranges, apples and bananas. (In American English, there would be a comma before 'and')
However, I need to use certain colon lists the members of which are either a mix of phrases and single-word items or only phrases.
Here is an example:
Signs of imbalance: inability to think clearly, acting out of rage, and impatience.
Signs of imbalance: inability to think clearly, impatience, and acting out of rage.
In cases such as below, I am using a comma before 'and' a) the list members are phrases(especially the last item) and not single-word items. b) the list members are a mix of phrases and single-word items. c) In general if I feel the list is somewhat complex and even if the last item is a single word.
I would like to know whether even for single item simple lists, I should use a comma before 'and' to maintain consistency OR whether I should use comma wherever I deem appropriate OR should I avoid comma even for the complex lists. I have also used phrases like 'and so on' but have not used a comma before them.
I request some clarity on the above.