<prompt> Rheumatoid factor in rheumatoid arthritis is important because -RA factor is associated with bad prognosisAbsent RA fact6r rules out the diagnosis of Rheumatoid arthritisIt is very common in childhood Rheumatoid arthritisIt correlates with disease activity  <response>: The chief value of the rheumatoid factor tests is in the assessment of prognosis : persistently high titers herold more serious disease including extra-articular features. Apley 