Statistics Notes: Measurement error

BMJ 1996;313:744 (21 September)

Education and debate

Statistics Notes: Measurement error

J Martin Bland, professor of medical statistics,^a Douglas G Altman, head ^b

^a Department of Public Health Sciences, St George's Hospital Medical School, London SW17 0RE, ^b IRCF Medical Statistics Group, Centre for Statistics in Medicine, Institute of Health Sciences, PO Box 777, Oxford OX3 7LF

Correspondence to: Professor Bland.

Several measurements of the same quantity on the same subjectwill not in general be the same. This may be because of naturalvariation in the subject, variation in the measurement process,or both. For example, table 1 shows four measurements of lungfunction in each of 20 schoolchildren (taken from a larger study¹).The first child shows typical variation, having peak expiratoryflow rates of 190, 220, 200, and 200 1/min.

Table 1--Repeated peak expiratory flow rate (PEFR) measurements for 20 schoolchildren --------------------------------------------------- Child No PEFR (l/min) Mean SD --------------------------------------------------- 1 190 220 200 200 202.50 12.58 2 220 200 240 230 222.50 17.08 3 260 260 240 280 260.00 16.33 4 210 300 280 265 263.75 38.60 5 270 265 280 270 271.25 6.29 6 280 280 270 275 276.25 4.79 7 260 280 280 300 280.00 . . . [Full text of this article]

Add to CiteULike CiteULike Add to Complore Complore Add to Connotea Connotea Add to Del.icio.us Del.icio.us Add to Digg Digg Add to Reddit Reddit Add to StumbleUpon StumbleUpon Add to Technorati Technorati What's this?

Relevant Article

Value of routine monitoring of bone mineral density after starting bisphosphonate treatment: secondary analysis of trial data: Katy J L Bell, Andrew Hayen, Petra Macaskill, Les Irwig, Jonathan C Craig, Kristine Ensrud, and Douglas C Bauer
BMJ 2009 338: b2266. [Abstract] [Full Text] [PDF]

This article has been cited by other articles:

Graff, C., Matz, J., Christensen, E. B., Andersen, M. P., Kanters, J. K., Toft, E., Pehrson, S., Hardahl, T. B., Nielsen, J., Struijk, J. J. (2009). Quantitative Analysis of T-wave Morphology Increases Confidence in Drug-Induced Cardiac Repolarization Abnormalities: Evidence From the Investigational IKr Inhibitor Lu 35-138. J Clin Pharmacol 49: 1331-1342 [Abstract] [Full text]
Maldonado, M. J., Lopez-Miguel, A., Nieto, J. C., Cano-Parra, J., Calvo, B., Alio, J. L. (2009). Reliability of Noncontact Pachymetry after Laser In Situ Keratomileusis. IOVS 50: 4135-4141 [Abstract] [Full text]
Iriart, X., Montaudon, M., Lafitte, S., Chabaneix, J., Reant, P., Balbach, T., Houle, H., Laurent, F., Thambo, J.-B. (2009). Right ventricle three-dimensional echography in corrected tetralogy of fallot: accuracy and variability. Eur J Echocardiogr 10: 784-792 [Abstract] [Full text]
van Dalen, B. M., Soliman, O. I.I., Vletter, W. B., Kauer, F., van der Zwaan, H. B., ten Cate, F. J., Geleijnse, M. L. (2009). Feasibility and reproducibility of left ventricular rotation parameters measured by speckle tracking echocardiography. Eur J Echocardiogr 10: 669-676 [Abstract] [Full text]
Meyer, T., Gaya, A. M., Dancey, G., Stratford, M. R.L., Othman, S., Sharma, S. K., Wellsted, D., Taylor, N. J., Stirling, J. J., Poupard, L., Folkes, L. K., Chan, P.-s., Pedley, R. B., Chester, K. A., Owen, K., Violet, J. A., Malaroda, A., Green, A. J., Buscombe, J., Padhani, A. R., Rustin, G. J., Begent, R. H. (2009). A Phase I Trial of Radioimmunotherapy with 131I-A5B7 Anti-CEA Antibody in Combination with Combretastatin-A4-Phosphate in Advanced Gastrointestinal Carcinomas. Clin. Cancer Res. 15: 4484-4492 [Abstract] [Full text]
Bell, K. J L, Hayen, A., Macaskill, P., Irwig, L., Craig, J. C, Ensrud, K., Bauer, D. C (2009). Value of routine monitoring of bone mineral density after starting bisphosphonate treatment: secondary analysis of trial data. BMJ 338: b2266-b2266 [Abstract] [Full text]
Patel, P. J., Chen, F. K., Rubin, G. S., Tufail, A. (2009). Intersession Repeatability of Contrast Sensitivity Scores in Age-Related Macular Degeneration. IOVS 50: 2621-2625 [Abstract] [Full text]
Gevers, S., Majoie, C.B.L.M., van den Tweel, X.W., Lavini, C., Nederveen, A.J. (2009). Acquisition Time and Reproducibility of Continuous Arterial Spin-Labeling Perfusion Imaging at 3T. Am. J. Neuroradiol. 30: 968-971 [Abstract] [Full text]
Wong, A L, Leung, C K-S, Weinreb, R N, Cheng, A K C, Cheung, C Y L, Lam, P T-H, Pang, C P, Lam, D S C (2009). Quantitative assessment of lens opacities with anterior segment optical coherence tomography. Br J Ophthalmol 93: 61-65 [Abstract] [Full text]
Nevarez, L., Vasseur, V., Le Drean, G., Tanguy, A., Guisle-Marsollier, I., Houlgatte, R., Barbier, G. (2008). Isolation and analysis of differentially expressed genes in Penicillium glabrum subjected to thermal stress. Microbiology 154: 3752-3765 [Abstract] [Full text]
Leung, C. K.-s., Cheung, C. Y.-l., Weinreb, R. N., Lee, G., Lin, D., Pang, C. P., Lam, D. S. C. (2008). Comparison of Macular Thickness Measurements between Time Domain and Spectral Domain Optical Coherence Tomography. IOVS 49: 4893-4897 [Abstract] [Full text]
Leung, C. K.-s., Cheung, C. Y.-l., Lin, D., Pang, C. P., Lam, D. S. C., Weinreb, R. N. (2008). Longitudinal Variability of Optic Disc and Retinal Nerve Fiber Layer Measurements. IOVS 49: 4886-4892 [Abstract] [Full text]
Ah-See, M.-L. W., Makris, A., Taylor, N. J., Harrison, M., Richman, P. I., Burcombe, R. J., Stirling, J. J., d'Arcy, J. A., Collins, D. J., Pittam, M. R., Ravichandran, D., Padhani, A. R. (2008). Early Changes in Functional Dynamic Magnetic Resonance Imaging Predict for Pathologic Response to Neoadjuvant Chemotherapy in Primary Breast Cancer. Clin. Cancer Res. 14: 6580-6589 [Abstract] [Full text]
Patel, P. J., Chen, F. K., Rubin, G. S., Tufail, A. (2008). Intersession Repeatability of Visual Acuity Scores in Age-Related Macular Degeneration. IOVS 49: 4347-4352 [Abstract] [Full text]
Moursi, M. M, Martin-Prevel, Y., Eymard-Duvernay, S., Capon, G., Treche, S., Maire, B., Delpeuch, F. (2008). Assessment of child feeding practices using a summary index: stability over time and association with child growth in urban Madagascar. Am. J. Clin. Nutr. 87: 1472-1479 [Abstract] [Full text]
Borg, A N, Harrison, J L, Argyle, R A, Ray, S G (2008). Left ventricular torsion in primary chronic mitral regurgitation. Heart 94: 597-603 [Abstract] [Full text]
Moreno-Montanes, J., Maldonado, M. J., Garcia, N., Mendiluce, L., Garcia-Gomez, P. J., Segui-Gomez, M. (2008). Reproducibility and Clinical Relevance of the Ocular Response Analyzer in Nonoperated Eyes: Corneal Biomechanical and Tonometric Implications. IOVS 49: 968-974 [Abstract] [Full text]
Kimberger, O., Cohen, D., Illievich, U., Lenhardt, R. (2007). Temporal Artery Versus Bladder Thermometry During Perioperative and Intensive Care Unit Monitoring. Anesth. Analg. 105: 1042-1047 [Abstract] [Full text]
Conradsson, M., Lundin-Olsson, L., Lindelof, N., Littbrand, H., Malmqvist, L., Gustafson, Y., Rosendahl, E. (2007). Berg Balance Scale: Intrarater Test-Retest Reliability Among Older People Dependent in Activities of Daily Living and Living in Residential Care Facilities. ptjournal 87: 1155-1163 [Abstract] [Full text]
Nicholson, P J (2007). How to undertake a systematic review in an occupational setting. Occup. Environ. Med. 64: 353-358 [Full text]
Zulian, F., Meneghesso, D., Grisan, E., Vittadello, F., Belloni Fortina, A., Pigozzi, B., Frigo, A. C., Martini, G., Ruggeri, A. (2007). A new computerized method for the assessment of skin lesions in localized scleroderma. Rheumatology (Oxford) 46: 856-860 [Abstract] [Full text]
Noble, D. D., McCafferty, J. B., Greening, A. P., Innes, J. A. (2007). Respiratory heat and moisture loss is associated with eosinophilic inflammation in asthma. Eur Respir J 29: 676-681 [Abstract] [Full text]
Montaudon, M., Berger, P., de Dietrich, G., Braquelaire, A., Marthan, R., Tunon-de-Lara, J. M., Laurent, F. (2006). Assessment of Airways with Three-dimensional Quantitative Thin-Section CT: In Vitro and in Vivo Validation. Radiology 0: 2422060029-0 [Abstract] [Full text]
Dame Carroll, J. R., Chandra, A., Jones, A. S., Berend, N., Magnussen, J. S., King, G. G. (2006). Airway dimensions measured from micro-computed tomography and high-resolution computed tomography. Eur Respir J 28: 712-720 [Abstract] [Full text]
Brown, L N, Metz, L M, Eliasziw, M (2006). Identifying reliable change in tactile temporal thresholds in multiple sclerosis: test-retest reliability. Mult Scler 12: 573-577 [Abstract]
Andersson, C., Asztalos, L., Mattsson, E. (2006). Six-minute walk test in adults with cerebral palsy. A study of reliability. Clin Rehabil 20: 488-495 [Abstract]
Zavorsky, G. S., Murias, J. M. (2006). A small amount of inhaled nitric oxide does not increase lung diffusing capacity. Eur Respir J 27: 1251-1257 [Abstract] [Full text]
Maruff, P, Snyder, P, McStephen, M, Collie, A, Darby, D (2006). Cognitive deterioration associated with an expedition in an extreme desert environment. Br. J. Sports. Med. 40: 556-560 [Abstract] [Full text]
Muller, M.J., Mazanek, M., Weibrich, C., Dellani, P.R., Stoeter, P., Fellgiebel, A. (2006). Distribution characteristics, reproducibility, and precision of region of interest-based hippocampal diffusion tensor imaging measures.. Am. J. Neuroradiol. 27: 440-446 [Abstract] [Full text]
Marcus, G. M., Rose, E., Viloria, E. M., Schafer, J., De Marco, T., Saxon, L. A., Foster, E., for the VENTAK CHF/CONTAK-CD Biventricular Pacing, (2005). Septal to Posterior Wall Motion Delay Fails to Predict Reverse Remodeling or Clinical Improvement in Patients Undergoing Cardiac Resynchronization Therapy. J Am Coll Cardiol 46: 2208-2214 [Abstract] [Full text]
Annet, L., Peeters, F., Horsmans, Y., Hermoye, L., Starkel, P., Van Beers, B. E. (2005). Esophageal Varices: Evaluation with Transesophageal MR Imaging--Initial Experience. Radiology 238: 167-175 [Abstract] [Full text]
Kotecha, A, White, E T, Shewry, J M, Garway-Heath, D F (2005). The relative effects of corneal thickness and age on Goldmann applanation tonometry and dynamic contour tonometry. Br J Ophthalmol 89: 1572-1575 [Abstract] [Full text]
Moreno-Montanes, J., Alvarez, A., Maldonado, M. J. (2005). Objective Quantification of Posterior Capsule Opacification after Cataract Surgery, with Optical Coherence Tomography. IOVS 46: 3999-4006 [Abstract] [Full text]
Carpagnano, G. E., Foschino Barbaro, M P., Cagnazzo, M., Di Gioia, G, Giliberti, T, Di Matteo, C, Resta, O (2005). Use of Exhaled Breath Condensate in the Study of Airway Inflammation After Hypertonic Saline Solution Challenge. Chest 128: 3159-3166 [Abstract] [Full text]
Berger, P., Perot, V., Desbarats, P., Tunon-de-Lara, J. M., Marthan, R., Laurent, F. (2005). Airway Wall Thickness in Cigarette Smokers: Quantitative Thin-Section CT Assessment. Radiology 235: 1055-1064 [Abstract] [Full text]
Hickman, S. J., Wheeler-Kingshott, C. A. M., Jones, S. J., Miszkiel, K. A., Barker, G. J., Plant, G. T., Miller, D. H. (2005). Optic Nerve Diffusion Measurement from Diffusion-Weighted Imaging in Optic Neuritis. Am. J. Neuroradiol. 26: 951-956 [Abstract] [Full text]
Hermoye, L., Laamari-Azjal, I., Cao, Z., Annet, L., Lerut, J., Dawant, B. M., Van Beers, B. E. (2005). Liver Segmentation in Living Liver Transplant Donors: Comparison of Semiautomatic and Manual Methods. Radiology 234: 171-178 [Abstract] [Full text]
Kournetas, N., Jaeger, B., Axmann, D., Groten, M., Lachmann, S., Weber, H., Geis-Gerstorfer, J. (2004). Assessing the Reliability of a Digital Preparation Assistant System Used in Dental Education. J Dent Educ 68: 1228-1234 [Abstract] [Full text]
Haugen, H., Magnusson, B., Svensson, M., Mercke, C. (2004). Preradiotherapy Hemoglobin Level but not Microvessel Density Predicts Locoregional Control and Survival in Laryngeal Cancer Treated with Primary Radical Radiotherapy. Clin. Cancer Res. 10: 7941-7949 [Abstract] [Full text]
Nirmalan, M., Niranjan, M., Willard, T., Edwards, J. D., Little, R. A., Dark, P. M. (2004). Estimation of errors in determining intrathoracic blood volume using thermal dilution in pigs with acute lung injury and haemorrhage. Br J Anaesth 93: 546-551 [Abstract] [Full text]
Lam, D. S. C., Leung, D. Y. L., Chiu, T. Y. H., Fan, D. S. P., Cheung, E. Y. Y., Wong, T.-Y., Lai, J. S. M., Tham, C. C. Y. (2004). Pressure Phosphene Self-Tonometry: A Comparison with Goldmann Tonometry in Glaucoma Patients. IOVS 45: 3131-3136 [Abstract] [Full text]
Lequesne, M, Malghem, J, Dion, E (2004). The normal hip joint space: variations in width, shape, and architecture on 223 pelvic radiographs. Ann Rheum Dis 63: 1145-1151 [Abstract] [Full text]
King, G.G., Carroll, J.D., Muller, N.L., Whittall, K.P., Gao, M., Nakano, Y., Pare, P.D. (2004). Heterogeneity of narrowing in normal and asthmatic airways measured by HRCT. Eur Respir J 24: 211-218 [Abstract] [Full text]
Wei, X., Guttmann, C. R., Warfield, S. K, Eliasziw, M., Mitchell, J R. (2004). Has your patient's multiple sclerosis lesion burden or brain atrophy actually changed?. Mult Scler 10: 402-406 [Abstract]
Carpagnano, G. E., Barnes, P. J., Francis, J., Wilson, N., Bush, A., Kharitonov, S. A. (2004). Breath Condensate pH in Children With Cystic Fibrosis and Asthma: A New Noninvasive Marker of Airway Inflammation?. Chest 125: 2005-2010 [Abstract] [Full text]
Zavorsky, G. S., Quiron, K. B., Massarelli, P. S., Lands, L. C. (2004). The Relationship Between Single-Breath Diffusion Capacity of the Lung for Nitric Oxide and Carbon Monoxide During Various Exercise Intensities. Chest 125: 1019-1027 [Abstract] [Full text]
Fiorella, D., Heiserman, J., Prenger, E., Partovi, S. (2004). Assessment of the Reproducibility of Postprocessing Dynamic CT Perfusion Data. Am. J. Neuroradiol. 25: 97-107 [Abstract] [Full text]
Padhani, A R (2003). MRI for assessing antivascular cancer treatments. Br. J. Radiol. 76: S60-S80 [Abstract] [Full text]
EREL, E., DILLEY, A., GREENING, J., MORRIS, V., COHEN, B., LYNN, B. (2003). Longitudinal Sliding of the Median Nerve in Patients with Carpal Tunnel Syndrome. J Hand Surg Eur Vol 28: 439-443 [Abstract] [Full text]
Carpagnano, G. E., Kharitonov, S. A., Resta, O., Foschino-Barbaro, M. P., Gramiccioni, E., Barnes, P. J. (2003). 8-Isoprostane, a Marker of Oxidative Stress, Is Increased in Exhaled Breath Condensate of Patients With Obstructive Sleep Apnea After Night and Is Reduced by Continuous Positive Airway Pressure Therapy. Chest 124: 1386-1392 [Abstract] [Full text]
Carpagnano, G. E., Barnes, P. J., Geddes, D. M., Hodson, M. E., Kharitonov, S. A. (2003). Increased Leukotriene B4 and Interleukin-6 in Exhaled Breath Condensate in Cystic Fibrosis. Am. J. Respir. Crit. Care Med. 167: 1109-1112 [Abstract] [Full text]
Cummings, P., Rivara, F. P. (2003). Reporting Statistical Information in Medical Journal Articles. Arch Pediatr Adolesc Med 157: 321-324 [Full text]
Valentine, J., Simpson, J. M (2002). Deciding whether a change in a patient's performance is a genuine change. Clin Rehabil 16: 837-842 [Abstract]
Halligan, S (2002). Reproducibility, repeatability, correlation and measurement error. Br. J. Radiol. 75: 193-194 [Full text]
Spenkelink, C D, Hutten, M M., Hermens, H J, Greitemann, B O. (2002). Assessment of activities of daily living with an ambulatory monitoring system: a comparative study in patients with chronic low back pain and nonsymptomatic controls. Clin Rehabil 16: 16-26 [Abstract]
Dyer, C A E, Singh, S J, Stockley, R A, Sinclair, A J, Hill, S L (2002). The incremental shuttle walking test in elderly people with chronic airflow limitation. Thorax 57: 34-38 [Abstract] [Full text]
Warke, T.J., Kamath, S., Fitch, P.S., Brown, V., Shields, M.D., Ennis, M. (2001). The repeatability of nonbronchoscopic bronchoalveolar lavage differential cell counts. Eur Respir J 18: 1009-1012 [Abstract] [Full text]
Silvestri, M, Sabatini, F, Spallarossa, D, Fregonese, L, Battistini, E, Biraghi, M G, Rossi, G A (2001). Exhaled nitric oxide levels in non-allergic and allergic mono- or polysensitised children with asthma. Thorax 56: 857-862 [Abstract] [Full text]
Auleley, G.-R., Duche, A., Drape, J.-L., Dougados, M., Ravaud, P. (2001). Measurement of joint space width in hip osteoarthritis: influence of joint positioning and radiographic procedure. Rheumatology (Oxford) 40: 414-419 [Abstract] [Full text]
Silvestri, M., Spallarossa, D., Battistini, E., Brusasco, V., Rossi, G. A (2000). Dissociation between exhaled nitric oxide and hyperresponsiveness in children with mild intermittent asthma. Thorax 55: 484-488 [Abstract] [Full text]
Walsh, T. S., McLellan, S., Mackenzie, S. J., Lee, A. (1999). Hyperlactatemia and Pulmonary Lactate Production in Patients With Fulminant Hepatic Failure. Chest 116: 471-476 [Abstract] [Full text]
Watt, V, Pickering, M, Wales, J K H (1998). A comparison of ultrasonic and mechanical stadiometry. Arch. Dis. Child. 78: 269-270 [Abstract] [Full text]
Masse, J., Bland, J M, Doyle, J R, Doyle, J M (1997). Measurement error. BMJ 314: 147-147 [Full text]