Myasoedova E, et al. - This study was carried out to analyze trends in the incidence of rheumatoid arthritis (RA) from 2005 to 2014 overall and by serological status as compared with 1995–2004 and 1985–1994. Between 1 January 1985 and 31 December 2014, researches examined RA incidence trends in a population-based inception cohort of individuals aged ≥18 years who first fulfilled the 1987 American College of Rheumatology (ACR) criteria for RA. In 2010. incidence rates were calculated and were age-adjusted and gender-adjusted to the white population in the USA.  The total number of individuals included in the study were 427: mean age 55.4 years, 68% female, 51% rheumatoid factor (RF) positive and 50% anti-cyclic citrullinated peptide antibody positive. Compared with previous decades, the study found significant increase in incidence of RF-negative RA and decrease in RF-positive RA in 2005–2014 using 1987 ACR criteria. It was noted that incidence of RA overall during this period remained similar to the previous decade. It is demonstrated that changing prevalence of environmental factors, such as smoking, obesity and others, may have contributed to these trends. If these trends represent a changing serological profile of RA needs future study.