CRP and ESR in acute diagnoses have limited use. I think the common sense blow torch should be applied when you order it – “Will it change my management?” If you are uncertain and think a high CRP may sway you to consider sending a patient to hospital then this could be appropriate use. If you are doing it ‘just to be safe’ then I would rethink your diagnosis and management and be more certain of your own skills – rather than relying on a possibly unhelpful test. Also, finally before ordering the test think to yourself “What if the result is NOT what I am expecting. What will I do then?”