Ethical guidelines in the United Kingdom require written consent from participants in epidemiologic studies for follow-up or review of medical records. This may cause bias in samples used for follow-up or medical record review. The authors analyzed data from seven general population surveys conducted in the United Kingdom (1996-2002), to which over 25,000 people responded. Associations of age, gender, and symptom under investigation with consent to follow-up and consent to review of medical records were examined. Consent to follow-up was approximately 75-95% among survey responders under age 50 years but fell among older people, particularly females. Consent to follow-up was also higher among responders who had the symptom under investigation (pooled odds ratio = 1.61, 95% confidence interval: 1.36, 1.92). Consent to review of medical records followed a similar pattern. Patterns of consent were relatively consistent and represented a high proportion of responders. Males, younger people, and subjects reporting the symptom under investigation were more likely to give consent, and these groups may be overrepresented in follow-up samples or reviews of medical records. Although consent is high among responders, the additive effect of nonresponse and nonconsent can substantially reduce sample size and should be taken into account in epidemiologic study planning.

Background: In longitudinal studies across a range of regional musculoskeletal pain syndromes, certain prognostic factors consistently emerge. They are ''generic'' in the sense that they appear to apply regardless of the particular anatomical site or underlying cause of the pain. Objective: To investigate the value of generic indicators of poor functional outcome for knee pain and osteoarthritis in the community. Methods: We conducted a population-based cohort study of adults aged >50 years with knee pain as part of the Clinical Assessment Study (Knee) (CAS(K)). At baseline, participants completed a postal questionnaire and attended a research clinic where they completed a further questionnaire and underwent structured physical examination and x rays. The 18-month follow-up was via a self-completed questionnaire. Risk ratios were calculated using Cox regression with a fixed time period assigned to each participant. Results: In total, 60% of participants experienced a poor outcome at 18 months. Twelve univariate associations were associated with poor outcome, with four variables remaining in the multivariate model (older age, being overweight or obese, having possible or probable anxiety, and more severe pain).Using a simple unweighted additive risk score (1 point each for age >60 years, body mass index >25 kg/m 2 , possible or probable anxiety, Chronic Pain Grade II-IV), 90% of participants with all four generic indicators were correctly classified.Conclusions: This study has demonstrated that generic prognostic indicators can be used to determine the prognosis of older people in the community with knee pain.

Background: Work-related neck and upper limb pain has mainly been studied in specific occupational groups, and little is known about its impact in the general population. The objectives of this study were to estimate the prevalence and population impact of work-related neck and upper limb pain.

Clinical history, physical examination and severity of radiographic knee OA are of limited value over generic factors when trying to predict which older adults with knee pain will experience progressive or persistent functional difficulties.

ObjectiveIn older adults, widespread pain (WP) is common, although its etiology is unclear. This study sought to identify factors associated with an increased risk of developing WP in adults age ≥50 years.MethodsA population‐based prospective study was conducted. A baseline questionnaire was administered to subjects to collect data on pain, psychological status, lifestyle and health behaviors, and sociodemographic and clinical factors. Participants free of WP (as defined by the American College of Rheumatology 1990 criteria for fibromyalgia) were followed up for 3 years, and those with new‐onset WP at followup were identified. Logistic regression analyses were used to test the relationship between baseline factors and new‐onset WP. Multiple imputation was used to test the results for sensitivity to missing data.ResultsIn this population‐based study, 4,326 subjects (1,562 reporting no pain at baseline and 2,764 reporting some pain at baseline) participated at followup. Of these participants, 800 (18.5%) reported a status of new WP at followup (of whom, 121 [7.7%] had reported no pain at baseline and 679 [24.6%] had reported some pain at baseline). The majority of the study factors were associated with new‐onset WP. However, only a few factors showed a persistent association with new‐onset WP in the multivariate analysis, including age (odds ratio [OR] 0.97, 95% confidence interval [95% CI] 0.96–0.99), baseline pain status (OR 1.1, 95% CI 1.08–1.2), anxiety (OR 1.5, 95% CI 1.01–2.1), physical health‐related quality of life (OR 1.3, 95% CI 1.1–1.5), cognitive complaint (OR 1.3, 95% CI 1.04–1.6), and nonrestorative sleep (OR 1.9, 95% CI 1.2–2.8). These associations persisted after adjustment for the presence of diffuse osteoarthritis (OA), which led to a modest increase in model fit (C‐statistic 0.738, compared with 0.731 in the model excluding diffuse OA). The results were not sensitive to missing data.ConclusionOf the factors measured in this study, nonrestorative sleep was the strongest independent predictor of new‐onset WP.

Study Design. Study of interrater reliability. Objective. To assess the interrater reliability of data from pain drawings scored by multiple raters and the consistency of the subsequent classification of cases of widespread pain.Summary of Background Data. In large health surveys, pain drawings used to capture self-reported pain, and to classify cases of widespread pain, are often scored by several raters. The reliability of multiple rater scoring of pain drawings has not been investigated.Methods. As part of a postal survey sent to adults 50 years and older, subjects were asked to shade their pain on a blank body manikin. The first 50 pain drawings in which respondents had shaded pain were selected for this study. Eight nonclinical staff were trained to score pain drawings using transparent templates divided into 50 body areas. Interrater reliability was assessed by comparing the scoring of "pain" or "no pain" for all 50 areas of each pain drawing.Results. Complete scoring agreement among all raters was observed for at least 78% of pain drawings across all body areas (kappa Ͼ 0.60). The raters had complete agreement in 42 of 50 areas in 90% or more of pain drawings. From the raters' scoring of pain areas, there was complete agreement on the presence or absence of widespread pain for 49 of 50 pain drawings (98% agreement, Kappa ϭ 0.98).Conclusions. This study shows that multiple raters, with training and guidelines, can reliably score pain drawings, and high consistency in the subsequent classification of cases of widespread pain can be obtained from such data.

Objectives. Number of pain sites (NPS) is a potentially important marker of health-related quality of life (HRQoL) but remains unexplored in older people. This cross-sectional study investigated whether, in older people including the oldest old, NPS was independently associated with poorer mental and physical HRQoL and if the association was moderated by age.Methods. A postal questionnaire sent to a population sample of adults aged ≥50 years in North Staffordshire, UK, included the 12-item Short Form Health Survey (SF-12) mental component summary (MCS) and physical component summary (PCS), a blank body pain manikin, socio-demographic, health behaviour and morbidity questions. Participants shaded sites of pain lasting ≥1 day in the past 4 weeks on the manikin. OA consultation data were obtained for participants consenting to medical records review.Results. A total of 13 986 individuals (adjusted response 70.6%) completed a questionnaire, of which 12 408 provided complete pain data. The median NPS reported was 4 [interquartile range (IQR) 0–8]. General linear models showed that an increasing NPS was significantly associated with poorer MCS (β = −0.43, 95% CI −0.46, −0.40) and PCS (β = −0.87, 95% CI −0.90, −0.84). Adjustment for covariates attenuated the associations but they remained significant (MCS: β = −0.28, 95% CI −0.31, −0.24; PCS: β = −0.63, 95% CI −0.66, −0.59). The association between NPS and MCS or PCS was moderated by age, but the strongest associations were not in the oldest old.Conclusion. NPS appears to be a potentially modifiable target for improving physical and mental HRQoL in older people. Future analyses should investigate the influence of NPS on HRQoL over time in older people.

Background: Selective non-participation at baseline (due to non-response and non-consent) and loss to follow-up are important concerns for longitudinal observational research. We investigated these matters in the context of baseline recruitment and retention at 18 months of participants for a prospective observational cohort study of knee pain and knee osteoarthritis in the general population.