The revised criteria for the classification of rheumatoid arthritis (RA) were formulated from a computerized analysis of 262 contemporary, consecutively studied patients with RA and 262 control subjects with rheumatic diseases other than RA (non-RA). The new criteria are as follows: 1) morning stiffness in and around joints lasting at least 1 hour before maximal improvement; 2) soft tissue swelling (arthritis) of 3 or more joint areas observed by a physician; 3) swelling (arthritis) of the proximal interphalangeal, metacarpophalangeal, or wrist joints; 4) symmetric swelling (arthritis); 5) rheumatoid nodules; 6) the presence of rheumatoid factor; and 7) radiographic erosions and/or periarticular osteopenia in hand and/or wrist joints. Criteria 1 through 4 must have been present for at least 6 weeks. Rheumatoid arthritis is defined by the presence of 4 or more criteria, and no further qualifications (classic, definite, or probable) or list of exclusions are required. In addition, a "classification tree" schema is presented which performs equally as well as the traditional (4 of 7) format. The new criteria demonstrated 91-94% sensitivity and 89% specificity for RA when compared with non-RA rheumatic disease control subjects.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/art.1780310302

The American Rheumatism Association 1987 revised criteria for the classification of rheumatoid arthritis.

Objective
To provide a single source for the best available estimates of the US prevalence of and number of individuals affected by osteoarthritis, polymyalgia rheumatica and giant cell arteritis, gout, fibromyalgia, and carpal tunnel syndrome, as well as the symptoms of neck and back pain. A companion article (part I) addresses additional conditions.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/art.23177

Estimates of the prevalence of arthritis and other rheumatic conditions in the United States. Part II.

OBJECTIVE
To provide a single source for the best available estimates of the US prevalence of and number of individuals affected by osteoarthritis, polymyalgia rheumatica and giant cell arteritis, gout, fibromyalgia, and carpal tunnel syndrome, as well as the symptoms of neck and back pain. A companion article (part I) addresses additional conditions.


METHODS
The National Arthritis Data Workgroup reviewed published analyses from available national surveys, such as the National Health and Nutrition Examination Survey and the National Health Interview Survey. Because data based on national population samples are unavailable for most specific rheumatic conditions, we derived estimates from published studies of smaller, defined populations. For specific conditions, the best available prevalence estimates were applied to the corresponding 2005 US population estimates from the Census Bureau, to estimate the number affected with each condition.


RESULTS
We estimated that among US adults, nearly 27 million have clinical osteoarthritis (up from the estimate of 21 million for 1995), 711,000 have polymyalgia rheumatica, 228,000 have giant cell arteritis, up to 3.0 million have had self-reported gout in the past year (up from the estimate of 2.1 million for 1995), 5.0 million have fibromyalgia, 4-10 million have carpal tunnel syndrome, 59 million have had low back pain in the past 3 months, and 30.1 million have had neck pain in the past 3 months.


CONCLUSION
Estimates for many specific rheumatic conditions rely on a few, small studies of uncertain generalizability to the US population. This report provides the best available prevalence estimates for the US, but for most specific conditions more studies generalizable to the US or addressing understudied populations are needed.

National Arthritis Data Work-group. Estimates of the prevalence of arthritis and other rheumatic conditions in the United States. Part II

Musculoskeletal conditions are a major burden on individuals, health systems, and social care systems, with indirect costs being predominant. This burden has been recognized by the United Nations and WHO, by endorsing the Bone and Joint Decade 2000-2010. This paper describes the burden of four major musculoskeletal conditions: osteoarthritis, rheumatoid arthritis, osteoporosis, and low back pain. Osteoarthritis, which is characterized by loss of joint cartilage that leads to pain and loss of function primarily in the knees and hips, affects 9.6% of men and 18% of women aged > 60 years. Increases in life expectancy and ageing populations are expected to make osteoarthritis the fourth leading cause of disability by the year 2020. Joint replacement surgery, where available, provides effective relief. Rheumatoid arthritis is an inflammatory condition that usually affects multiple joints. It affects 0.3-1.0% of the general population and is more prevalent among women and in developed countries. Persistent inflammation leads to joint destruction, but the disease can be controlled with drugs. The incidence may be on the decline, but the increase in the number of older people in some regions makes it difficult to estimate future prevalence. Osteoporosis, which is characterized by low bone mass and microarchitectural deterioration, is a major risk factor for fractures of the hip, vertebrae, and distal forearm. Hip fracture is the most detrimental fracture, being associated with 20% mortality and 50% permanent loss in function. Low back pain is the most prevalent of musculoskeletal conditions; it affects nearly everyone at some point in time and about 4-33% of the population at any given point. Cultural factors greatly influence the prevalence and prognosis of low back pain.

/pdf/burden-of-major-musculoskeletal-conditions-1xayk0ikb2.pdf

Burden of major musculoskeletal conditions

Objective
To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain).

Methods
The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020.

Results
Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form or arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected.

Conclusion
Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/1529-0131%28199805%2941%3A5%3C778%3A%3AAID-ART4%3E3.0.CO%3B2-V

Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States

Of 563 individuals suspected of having rheumatoid arthritis when examined in 1959-1960, only 402, or 71.4 per cent, participated in the Tecumseh, Michigan, Community Health Study of 1962-1965. Of the 402, when classified by similar criteria, only 107, or 26.6 per cent, maintained their former classification as to degree of certainty of presence of rheumatoid arthritis, while 200, or 49.8 per cent, showed no evidence of the disease. The results illustrate some of the difficulties and uncertainties of prospective studies.

/pdf/a-four-year-follow-up-of-suspected-rheumatoid-arthritis-the-at07h6lq2e.pdf

A four year follow-up of suspected rheumatoid arthritis: the Tecumseh, Michigan, Community Health Study.

https://deepblue.lib.umich.edu/bitstream/handle/2027.42/27568/0000612.pdf;sequence=1

Prevalence of radiologically defined osteoarthritis in the finger and wrist joints of adult residents of Tecumseh, Michigan, 1962-65.

Serum Uric Acid Concentration Among Business Executives: With Observations on Other Coronary Heart Disease Risk Factors

Rheumatism and Arthritis: Review of American and English Literature of Recent Years: (Fifteenth Rheumatism Review)

https://www.amjmed.com/article/0002-9343(64)90129-9/pdf

William M. Mikkelsen

Papers

A four year follow-up of suspected rheumatoid arthritis: the Tecumseh, Michigan, Community Health Study.

Prevalence of radiologically defined osteoarthritis in the finger and wrist joints of adult residents of Tecumseh, Michigan, 1962-65.

Serum Uric Acid Concentration Among Business Executives: With Observations on Other Coronary Heart Disease Risk Factors

Rheumatism and Arthritis: Review of American and English Literature of Recent Years: (Fifteenth Rheumatism Review)

Observations on the natural history of hyperuricemia and gout: I. An eighteen tear follow-up of nineteen gouty families☆