The Chingford Study population was established in 1989 as a retrospective case-control study to determine prevalence rates of osteoarthritis (OA) and osteoporosis (OP) in middle-aged women in the general population, and to assess a number of known risk factors and their associations with these two diseases. It has since become a prospective population-based longitudinal cohort of women seen annually and described in detail (Hart DJ & Spector TD). It is listed by the NIH as an important epidemiological resource and one of the few such cohorts with wide-ranging musculoskeletal data. .
The original response rate of the sample was 78%. The cohort consisted originally of 1003 middle-aged women aged 45-64 from a general practice in Chingford, North-East London. Since 1989 the women have been assessed annually with a number of investigations. At the beginning of the 15th year of the study 776 women are still attending the clinic, 77% of the original cohort. Eighty-four women have died, 62 women have moved away and 81 women have left the study. The women in the study are flagged and their deaths and any cancers are being tracked and reported to us through Office of National Statistics. The adjusted response rate (minus those who can no longer participate) is 85%. Reasons for attaining such a good response rate include close location of the clinic, continuity of well-prepared staff, care and preparation for each visit, and close GP liaison. The women are confident of an efficient service enabling the annual visit to be very time and cost effective.
The primary focus to date has been the study of the natural history of osteoarthritis and osteoporosis. A number of clinical, anthropometric, psychosocial, radiological and metabolic variables have been collected at two or more time points. Investigations have been carried out on all subjects and DNA samples on 900 individuals have been collected at least twice between 1994 and 2000. Almost 60 publications (in high quality rheumatology and bone journals) have been based on data from this cohort. A summary of the is available.
The strength of the Chingford Study in the last 5 years has been its use for collaborative research due to the detail of the longitudinal data. We have been able to determine not only common risk factors for musculo-skeletal disease within the subjects, but to investigate associated genetic and biologic phenotypes in the cohort and explore new methodology in imaging longitudinal changes in these common diseases.