Related Experiment Videos
Worldwide prevalence of juvenile arthritis why does it vary so much?
Prudence Joan Manners1, Carol Bower
1Department of Paediatrics, University of Western Australia, Perth, Australia. pruem@paed.uwa.edu.au
Insights
Epidemiological studies show wide variations in childhood arthritis prevalence and incidence. Differences in diagnostic criteria, case ascertainment, and study methodology contribute to these discrepancies in juvenile arthritis (JA) research.
Area of Science:
- Pediatric Rheumatology
- Epidemiology
- Public Health
Background:
- Juvenile arthritis (JA) encompasses various forms of childhood arthritis, including juvenile rheumatoid arthritis, juvenile chronic arthritis, and juvenile idiopathic arthritis.
- Epidemiological studies since 1966 have reported a broad range of prevalence and incidence rates for JA.
- Understanding these variations is crucial for accurate public health assessments and resource allocation.
Purpose of the Study:
- To review epidemiological studies of childhood arthritis published since 1966.
- To identify the key factors contributing to the wide variability in reported prevalence and incidence rates of juvenile arthritis (JA).
Main Methods:
- A comprehensive literature review was conducted, analyzing 34 epidemiological studies on JA published from 1966 onwards.
- Studies were evaluated for methodologies related to diagnostic criteria, case ascertainment, and study populations.
Main Results:
- Reported prevalence of JA varied from 0.07 to 4.01 per 1000 children, with annual incidence ranging from 0.008 to 0.226 per 1000 children.
- Significant discrepancies were attributed to diagnostic difficulties, evolving diagnostic criteria, differing case definitions, and variations in case ascertainment methods (community-based vs. clinical studies).
- Community-based studies, including previously undiagnosed cases, reported higher prevalence rates compared to clinical case studies.
Conclusions:
- Numerous factors contribute to the wide discrepancies in reported JA prevalence and incidence rates.
- Standardized diagnostic criteria and case ascertainment methods are essential for future studies to achieve greater consistency in results.
- Community-based research designs that capture undiagnosed cases provide a more comprehensive prevalence estimate for juvenile arthritis.
Objective:
To review epidemiological studies of childhood arthritis from 1966, and to identify possible reasons for the wide-ranging results for both prevalence and incidence of juvenile arthritis (JA). JA is the term used here collectively for juvenile rheumatoid arthritis, juvenile chronic arthritis, or juvenile idiopathic arthritis as defined in the respective published studies.
Methods:
A review of 34 epidemiological studies of JA since 1966 was undertaken.
Results:
Prevalence of JA is reported as 0.07 to 4.01 per 1000 children. Annual incidence is reported as 0.008 to 0.226 per 1000 children. The major factors contributing to differences in estimates include (1) factors due to diagnostic difficulties, to the development of new diagnostic criteria, and to the differing definitions of clinical cases; (2) differences in case ascertainment (community based versus clinical case studies, qualification and experience of study clinicians, definition of study population); (3) factors occurring with the passage of time, i.e., standard of living, health care resources, and increasing knowledge; and (4) small studies and hence more chance fluctuation. The major variation in reported prevalence was due to the difference between true community based studies involving children from within classrooms or homes (and not necessarily previously diagnosed with JA) compared with clinical case studies of children who (by definition) had been previously diagnosed. The highest prevalence was reported for true community based studies.
Conclusion:
Many factors contribute to the discrepancies between reported prevalence and incidence for JA. Studies based truly in the community reported the highest prevalence, as previously undiagnosed cases were included. Future studies involving standardized criteria and standardized case ascertainment done by fully trained clinicians should show greater consistency of results.