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Walsh CP, Lindsay EK, Grosse P, Natale BN, Fairlie S, Bwint A, Schaffer L, McMahon K, Del Duke C, Forse J, Lamonja-Vicente N, Marsland AL. A systematic review and meta-analysis of the stability of peripheral immune markers in healthy adults. Brain Behav Immun 2023; 107:32-46. [PMID: 36152782 PMCID: PMC9729419 DOI: 10.1016/j.bbi.2022.09.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 09/09/2022] [Accepted: 09/16/2022] [Indexed: 01/03/2023] Open
Abstract
Peripheral immune markers are widely used to predict risk for inflammatory disease. However, whether single assessments of inflammatory biomarkers represent stable individual differences remains unclear. We reviewed 50 studies (N = 48,674; 57 % male; mean age 54 (range 13-79) years) that assessed markers of inflammation on >1 occasion, with time between measures ranging from 24 h to 7+ years. Separate random effects meta-analyses were conducted for each inflammatory marker and time interval. Markers that had broad coverage across most time intervals included C-reactive protein (CRP; k = 37), interleukin (IL)-6 (k = 22), TNF-α (k = 10), and fibrinogen (Fg; k = 9). For CRP, IL-6, and TNF-α, stability estimates generally decreased with time, with strong to moderate stability over intervals <6 months (r's = 0.80-0.61), modest to moderate stability over 6 months - 3 years (r's = 0.60-0.51), and low stability for >3 years (r's = 0.39-0.30). Estimates were less reliable for Fg for time intervals ≤ 3 years although they generally followed the same pattern; more reliable findings suggested greater stability for Fg than other markers for intervals >3 years (r = 0.53). These findings suggest that single measures of inflammatory biomarkers may be an adequate index of stable individual differences in the short term (<6 months), with repeated measures of inflammatory biomarkers recommended over intervals ≥ 6 months to 3 years, and absolutely necessary over intervals >3 years to reliably identify stable individual differences in health risk. These findings are consistent with stability estimates and clinical recommendations for repeated measurement of other cardiovascular measures of risk (e.g., blood lipids, blood pressure).
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Affiliation(s)
- Catherine P Walsh
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
| | - Emily K Lindsay
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
| | - Philip Grosse
- Clinical and Translational Science Institute, Forbes Tower, Suite 7057, Pittsburgh, PA 15213, USA.
| | - Brianna N Natale
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
| | - Samantha Fairlie
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
| | - Amanda Bwint
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
| | - Luke Schaffer
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
| | - Katie McMahon
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
| | - Colin Del Duke
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
| | - Jenny Forse
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
| | - Noemi Lamonja-Vicente
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA; Department of Clinical Psychology and Psychobiology, Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Anna L Marsland
- Department of Psychology, University of Pittsburgh, 210 Bouquet St., Pittsburgh, PA, USA.
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Baumert J, Karakas M, Greven S, Rückerl R, Peters A, Koenig W. Variability of fibrinogen measurements in post-myocardial infarction patients. Thromb Haemost 2017; 107:895-902. [DOI: 10.1160/th11-10-0703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 01/18/2012] [Indexed: 11/05/2022]
Abstract
SummaryElevated fibrinogen levels are strongly and consistently associated with incident coronary heart disease (CHD). A possible causal contribution of fibrinogen in the pathway leading to atherothrombotic cardiovascular disease complications has been suggested. However, for implementation in clinical practice, data on validity and reliability, which are still scarce, are needed that are still scarce, especially in subjects with a history of CHD. For the present study, levels of plasma fibrinogen were measured in 200 post-myocardial infarction (post-MI) patients aged 39–76 years, with approximately six blood samples collected at monthly intervals between May 2003 and March 2004, giving a total of 1,144 samples. Inter-individual variability (between-subject variance component, VCb and coefficient of variation, CVb), intra-individual and analytical variability (VCw+a and CVw+a), intraclass correlation coefficient (ICC) and the number of measurements required for an ICC of 0.75 were estimated to assess the reliability of serial fibrinogen measurements. Mean fibrinogen concentration of all subjects over all samples was 3.34 g/l (standard deviation 0.67). Between-subject variation for fibrinogen was VCb = 0.34 (CVb,=17.5%) whereas within-subject and analytical variation was estimated as VCw+a = 0.14 (CVw+a=11.0%). The variation was mainly explained by between-subject variability, shown by the proportion of total variance of 71.3%. Two different measurements were required to reach sufficient reliability, if subjects with extreme values were not excluded. The present study indicates a fairly good reproducibility of serial individual fibrinogen measurements in post-MI subjects.
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Tofler GH, Massaro J, Levy DA, Sutherland PA, Buckley T, D’Agostino RB. Increased heart rate is associated with a prothrombotic state: The Framingham Heart Study. Eur J Prev Cardiol 2016; 24:382-388. [DOI: 10.1177/2047487316679902] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Geoffrey H Tofler
- Royal North Shore Hospital, Australia
- University of Sydney, Australia
| | | | - Daniel A Levy
- The Framingham Heart Study of the National Heart Lung and Blood Institute of the National Institutes of Health, USA
- Boston University School of Medicine, USA
| | - Patrice A Sutherland
- The Framingham Heart Study of the National Heart Lung and Blood Institute of the National Institutes of Health, USA
- Boston University School of Medicine, USA
| | - Thomas Buckley
- Royal North Shore Hospital, Australia
- University of Sydney, Australia
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Jackson SE, van Jaarsveld CH, Beeken RJ, Gunter MJ, Steptoe A, Wardle J. Four-year stability of anthropometric and cardio-metabolic parameters in a prospective cohort of older adults. Biomark Med 2015; 9:109-22. [PMID: 25689899 DOI: 10.2217/bmm.14.78] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AIM To examine the medium-term stability of anthropometric and cardio-metabolic parameters in the general population. MATERIALS & METHODS Participants were 5160 men and women from the English Longitudinal Study of Ageing (age ≥50 years) assessed in 2004 and 2008. Anthropometric data included height, weight, BMI and waist circumference. Cardio-metabolic parameters included blood pressure, serum lipids (total cholesterol, HDL, LDL, triglycerides), hemoglobin, fasting glucose, fibrinogen and C-reactive protein. RESULTS Stability of anthropometric variables was high (all intraclass correlations >0.92), although mean values changed slightly (-0.01 kg weight, +1.33 cm waist). Cardio-metabolic parameters showed more variation: correlations ranged from 0.43 (glucose) to 0.81 (HDL). The majority of participants (71-97%) remained in the same grouping relative to established clinical cut-offs. CONCLUSION Over a 4-year period, anthropometric and cardio-metabolic parameters showed good stability. These findings suggest that when no means to obtain more recent data exist, a one-time sample will give a reasonable approximation to average levels over the medium-term, although reliability is reduced.
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Affiliation(s)
- Sarah E Jackson
- Health Behaviour Research Centre, Department of Epidemiology & Public Health, University College London, London, UK
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Alexander KS, Kazmierczak SC, Snyder CK, Oberdorf JA, Farrell DH. Prognostic utility of biochemical markers of cardiovascular risk: impact of biological variability. Clin Chem Lab Med 2014; 51:1875-82. [PMID: 23648634 DOI: 10.1515/cclm-2012-0750] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 04/05/2013] [Indexed: 01/06/2023]
Abstract
BACKGROUND Although a variety of biochemical markers are used to help predict the risk of cardiovascular disease, the prognostic utility of any marker used as a risk assessment tool is dependent on the long- and short-term biological variability that the marker shows in different individuals. METHODS We measured total, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol; triglycerides; high-sensitivity C-reactive protein (hsCRP); total fibrinogen; and γ' fibrinogen in blood samples collected from 15 apparently healthy individuals over the course of 1 year. Repeated measures variation estimates were used to calculate short- and long-term intraclass correlation coefficients (ICC), within- and between-subject coefficients of variation (CVI and CVG, respectively), validity coefficients, and indices of individuality for each marker. RESULTS HDL cholesterol demonstrated the lowest variability profile, with an ICC of 0.84 and CVI of 11.1 (95% CI: 8.3, 17.0). hsCRP showed the highest levels of short- and long-term within-subject variability [CVI (95% CI): 54.8 (32.8, 196.3) and 77.1 (53.3, 141.3), respectively]. Stated differently, it would require five separate measurements of hsCRP, performed on samples collected over multiple days, to provide the risk assessment information provided by a single measurement of HDL cholesterol. γ' Fibrinogen demonstrated an ICC of 0.79 and CVI of 14.3 (95% CI: 10.6, 21.9). CONCLUSIONS hsCRP showed very high biological variability, such that a single measurement of hsCRP lacks sufficient clinical utility to justify routine measurement. The variability profile of γ' fibrinogen was not markedly different than HDL cholesterol, necessitating only a limited number of measurements to establish an individual's risk of cardiovascular disease.
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Kampus P, Muda P, Kals J, Ristimäe T, Fischer K, Teesalu R, Zilmer M. The relationship between inflammation and arterial stiffness in patients with essential hypertension. Int J Cardiol 2006; 112:46-51. [PMID: 16297996 DOI: 10.1016/j.ijcard.2005.08.026] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2005] [Revised: 08/19/2005] [Accepted: 08/20/2005] [Indexed: 02/03/2023]
Abstract
BACKGROUND Data about the correlation between augmentation index (AIx), timing of the reflected waveform (T(r)) and inflammatory markers in patients with essential hypertension are not yet well established. The aim of this study was to compare plasma high-sensitivity C-reactive protein (hsCRP), white blood cell count and fibrinogen in hypertensive patients and in normotensive controls and to assess the relationship between inflammatory markers and arterial stiffness. METHODS Forty-two healthy middle-aged patients with untreated stage I-II essential hypertension and 42 sex- and age-matched controls were recruited in the study. Pulse wave analysis was used to assess AIx and T(r). RESULTS Plasma hsCRP, white blood cell count, AIx and T(r) were significantly higher in the patients with essential hypertension. In multiple regression analysis, AIx correlated positively with age, female gender, mean arterial pressure and log(hsCRP), and negatively with heart rate and height (R(2)=0.75, p<0.001). T(r) correlated negatively with log(hsCRP) (r=-0.34, p=0.002) for the whole study group. However, after adjusting for mean arterial pressure, age, height, heart rate and sex to the regression model, no correlation was revealed between log(hsCRP) and T(r) (p=0.35) as the dependent variable (R(2)=0.48, p<0.001). CONCLUSIONS Untreated hypertensive patients with low or moderate total cardiovascular risk had significantly increased blood hsCRP and white blood cell count and arterial stiffness, expressed as AIx and T(r). AIx correlated independently with hsCRP in multiple regression analysis. Measurement of arterial stiffness and inflammation can be suggested as an additional tool to assess cardiovascular risk in hypertensive patients with low or moderate total cardiovascular risk as estimated by traditional risk factors.
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Affiliation(s)
- Priit Kampus
- Department of Cardiology, University of Tartu, 8 Puusepa Street, Tartu 51014, Estonia.
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Clays E, De Bacquer D, Delanghe J, Kittel F, Van Renterghem L, De Backer G. Associations Between Dimensions of Job Stress and Biomarkers of Inflammation and Infection. J Occup Environ Med 2005; 47:878-83. [PMID: 16155472 DOI: 10.1097/01.jom.0000171056.22917.ad] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The objective of this study was to examine associations between dimensions of job stress and indicators of chronic inflammation and infection. METHODS Within a subsample from the BELSTRESS study of 892 male subjects free of cardiovascular disease, dimensions of job stress from the job demand-control-support model were related to biomarkers of inflammation (plasma fibrinogen concentrations, high-sensitivity C-reactive protein, and serum amyloid A) and infection (titers against Chlamydia pneumoniae, cytomegalovirus, and Helicobacter pylori). RESULTS A negative association was found between job control and plasma fibrinogen concentration, independent from age, education, occupation, body mass index, smoking, alcohol consumption, and use of lipid-lowering and antihypertensive medication. Higher social support at work was independently related to an increased risk of positive titers against cytomegalovirus. CONCLUSIONS Results confirm previous findings regarding elevated plasma fibrinogen and low job control.
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Affiliation(s)
- Els Clays
- Department of Public Health, Ghent University, University Hospital, Belgium.
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Bruno A, McConnell JP, Cohen SN, Tietjen GE, Richardson D, Gorelick PB, Bang NU. Plasma thrombosis markers following cerebral infarction in African Americans. Thromb Res 2005; 115:73-7. [PMID: 15567456 DOI: 10.1016/j.thromres.2004.06.043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2004] [Revised: 06/25/2004] [Accepted: 06/28/2004] [Indexed: 10/26/2022]
Affiliation(s)
- Askiel Bruno
- Department of Neurology, Indiana University School of Medicine, 541 Clinical Drive, Room 292, Indianapolis, IN 46202-5111, USA.
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Browning LM, Krebs JD, Jebb SA. Discrimination ratio analysis of inflammatory markers: implications for the study of inflammation in chronic disease. Metabolism 2004; 53:899-903. [PMID: 15254884 DOI: 10.1016/j.metabol.2004.01.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
To understand the role of inflammation in chronic disease it is important to have a reliable measure of habitual inflammatory status. A number of acute-phase response markers have been used as measures of inflammatory status, but the ability of a single measure to appropriately reflect habitual inflammatory status has not been assessed. This study compares the ability of different inflammatory markers to characterize habitual inflammatory status in overweight women. A single fasting blood sample was taken from 86 overweight women (mean body mass index [BMI], 35.2 kg/m2; range, 26.2 to 47.6 kg/m2) and a number of inflammatory markers (both acute-phase response markers and cytokines) were measured. A randomly selected subpopulation of 15 women attended on 2 further occasions for further blood samples. Using the subpopulation, discrimination ratios (DRs) were calculated for each inflammatory marker to assess the within-subject variability. The DRs were then used to determine the relationship between these markers, adjusted for within-subject variability, in the whole population. In this highly controlled experimental environment, interleukin-6 (IL-6), with a DR of 3.71, was the cytokine with the greatest ability to discriminate between subjects, suggesting that it is best able to characterize habitual inflammatory status. Sialic acid was the acute-phase response marker with the highest DR (3.16), and showed stronger correlations with other inflammatory markers, including C-reactive protein (CRP), than IL-6. This study suggests that use of some inflammatory markers, such as CRP, with large within-individual variability, will underestimate the relationship between inflammation and disease, and thus relationships between inflammation and chronic disease may be stronger than previously appreciated. Future studies should consider IL-6 or sialic acid to provide a more robust measure of inflammatory status.
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Affiliation(s)
- L M Browning
- The Medical Research Council Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, UK
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Cunningham MT, Brandt JT, Laposata M, Olson JD. Laboratory diagnosis of dysfibrinogenemia. Arch Pathol Lab Med 2002; 126:499-505. [PMID: 11900586 DOI: 10.5858/2002-126-0499-ldod] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Dysfibrinogenemia is a coagulation disorder caused by a variety of structural abnormalities in the fibrinogen molecule that result in abnormal fibrinogen function. It can be inherited or acquired. The inherited form is associated with increased risk of bleeding, thrombosis, or both in the same patient or family. Traditionally, dysfibrinogenemia is diagnosed by abnormal tests of fibrin clot formation; the thrombin time and reptilase time are the screening tests, and the fibrinogen clotting activity-antigen ratio is the confirmatory test. The inherited form is diagnosed by demonstrating similar laboratory test abnormalities in family members, and if necessary by analysis of the fibrinogen protein or fibrinogen genes in the patient. The acquired form is diagnosed by demonstrating abnormal liver function tests and by ruling out dysfibrinogenemia in family members. This article reviews the laboratory testing of dysfibrinogenemia and presents an algorithm for sequential test selection that can be used for diagnosis.
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Affiliation(s)
- Mark T Cunningham
- Department of Pathology, University of Kansas Medical Center, Kansas City, 66160, USA.
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Rosenson RS, Mosca L, Staffileno BA, Tangney CC. Variability in fibrinogen measurements: an obstacle to cardiovascular risk stratification. Atherosclerosis 2001; 159:225-30. [PMID: 11689225 DOI: 10.1016/s0021-9150(01)00503-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The clinical utility of fibrinogen measurement has been limited by large intraindividual variability. Several approaches that have been shown to improve the repeatability of fibrinogen include acquisition of samples at the same time of day, standardized sample procurement techniques, and multiple replicate sampling. This study employed established pre-analytical and analytical techniques known to reduce fibrinogen variability, including the acquisition of three replicate samples, each analyzed in duplicate, to evaluate the impact of intraindividual variability in fibrinogen measurement at baseline and 3 months on cardiovascular risk in 60 healthy subjects. Classification accuracy was evaluated by the ability to categorize subjects into tertiles of fibrinogen. Only 55% (33/60) of the subjects were correctly assigned to the appropriate fibrinogen tertile. Fibrinogen measurements varied by more than 10% in 45% of subjects and by 5% in 80% of subjects. Intraindividual variability in fibrinogen measurement with a functional assay limits cardiovascular risk assessment even when three replicates are averaged.
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Affiliation(s)
- R S Rosenson
- Department of Medicine and Pathology, Lipoprotein and Hemorheology Research Facility, Preventive Cardiology Center, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60611, USA.
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Carroll S, Cooke CB, Butterly RJ. Leisure time physical activity, cardiorespiratory fitness, and plasma fibrinogen concentrations in nonsmoking middle-aged men. Med Sci Sports Exerc 2000; 32:620-6. [PMID: 10731004 DOI: 10.1097/00005768-200003000-00011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE The relationship of both leisure time physical activity and predicted maximum oxygen consumption (VO2max) with plasma fibrinogen concentration was examined within a cohort of employed middle-aged men. METHODS Analyses were performed on a subsample of 635 nonsmoking men (46.7 +/- 7.7 yr) who completed a preventive medical assessment between 1992 and 1996. RESULTS Among nonsmokers, mean age-adjusted fibrinogen concentration decreased significantly with higher physical activity index (PAL) categories and quartiles of predicted VO2max (mL x kg(-1) x min(-1)) (both P = 0.001). Mean age-adjusted plasma fibrinogen concentrations were significantly different (P < 0.05) between inactive and vigorous PAI groups and extreme quartiles of predicted VO2max (mL x kg(-1) x min(-1)). These relationships were no longer significant after adjustment for the confounding effect of other ischemic heart disease risk factors. Stepwise multiple regression analyses showed that age, sum of skinfolds, and blood leukocyte count were the strongest predictors of plasma fibrinogen concentration. CONCLUSION These data do not confirm a significant independent association of both physical activity and predicted VO2max (mL x kg(-1) x min(-1)) with fibrinogen concentrations among nonsmoking middle-aged men of similar high social class.
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Affiliation(s)
- S Carroll
- School of Leisure and Sports Studies, Leeds Metropolitan University, United Kingdom
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Ravaud P, Giraudeau B, Auleley GR, Edouard-Noël R, Dougados M, Chastang C. Assessing smallest detectable change over time in continuous structural outcome measures: application to radiological change in knee osteoarthritis. J Clin Epidemiol 1999; 52:1225-30. [PMID: 10580786 DOI: 10.1016/s0895-4356(99)00109-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Interpreting changes in continuous structural outcome measures is a common problem in clinical research and in daily practice. We propose a method for estimating whether difference observed between two successive measures in an individual constitutes a statistically relevant change or a change induced by variability. This statistically relevant change is based on an analysis of reproducibility. The continuous structural outcome measure investigated as an example was joint space width (JSW) measurement on standard X-rays, which is known to be the primary end-point for assessing structural osteoarthritis progression. The results of the present study demonstrate that cutoffs are closely dependent on all sources of variabilities in JSW measurement such as joint positioning, radiographic procedure, and the measurement process itself. Therefore, we suggest to determine cutoffs for each study using a representative sample of the population studied and using the procedures and methods of measurement of the specific study. This approach may easily be extended to other continuous structural outcome measures.
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Affiliation(s)
- P Ravaud
- Clinique de Rhumatologie, Hôpital Cochin et Université René Descartes, Paris, France
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Affiliation(s)
- H H Vorster
- Department of Nutrition, Potchefstroom Universiteit, Republic of South Africa.
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