Repeated measures in clinical trials: Analysis using mean summary statistics and its implications for design
Abstract
This paper explores the use of simple summary statistics for analysing repeated measurements in randomized clinical trials with two treatments. Quite often the data for each patient may be effectively summarized by a pre‐treatment mean and a post‐treatment mean. Analysis of covariance is the method of choice and its superiority over analysis of post‐treatment means or analysis of mean changes is quantified, as regards both reduced variance and avoidance of bias, using a simple model for the covariance structure between time points. Quantitative consideration is also given to practical issues in the design of repeated measures studies: the merits of having more than one pre‐treatment measurement are demonstrated, and methods for determining sample sizes in repeated measures designs are provided. Several examples from clinical trials are presented, and broad practical recommendations are made. The examples support the value of the compound symmetry assumption as a realistic simplification in quantitative planning of repeated measures trials. The analysis using summary statistics makes no such assumption. However, allowance in design for alternative non‐equal correlation structures can and should be made when necessary.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
Hypothesis testing used ANCOVA adjusted for baseline differences for primary and secondary outcomes.
“Hypothesis testing was conducted via SPSS version 23 software (IBM Corp., Armonk, NY) using an analysis of covariance (ANCOVA) strategy 29 for primary (i.e., pain intensity and pain unpleasantness) and secondary outcomes (anxiety, relaxation, pleasant body sensations, desire for opioids), adjusted for baseline differences.”
From Randomized Controlled Trial of Brief Mindfulness Training and Hypnotic Suggestion for Acute Pain Relief in the Hospital Setting. (2017) · cites this paper as [29]
Cites
The Design and Analysis of Clinical Experiments.
Hills, M., & Fleiss, J. L. (1987) · Journal of the Royal Statistical Society Series A (General) · doi:10.2307/2982050 · Cited by 3,261 · see citing works
Analysis of serial measurements in medical research.
Matthews, J. N. S., Altman, D. G., Campbell, M. J., & Royston, P. J. (1990) · BMJ · doi:10.1136/bmj.300.6719.230 · Cited by 3,137 · see citing works
Procedures for Comparing Samples with Multiple Endpoints
O’Brien, P. C. (1984) · Biometrics · doi:10.2307/2531158 · Cited by 1,163 · see citing works
Analysis of Repeated Measures.
ELASHOFF, J. D., Crowder, M. J., & Hand, D. J. (1991) · Journal of the American Statistical Association · doi:10.2307/2290432 · Cited by 940 · see citing works
Statistical Problems in the Reporting of Clinical Trials
Pocock, S., Hughes, M. D., & Lee, R. J. (1987) · New England Journal of Medicine · doi:10.1056/nejm198708133170706 · Cited by 660 · see citing works
Self-citationThe Analysis of Multiple Endpoints in Clinical Trials
Pocock, S. J., Geller, N. L., & Tsiatis, A. A. (1987) · Biometrics · doi:10.2307/2531989 · Cited by 524 · see citing works
Self-citationWu, M. C., & Bailey, K. R. (1989) · Biometrics · doi:10.2307/2531694 · Cited by 372 · see citing works
COMPARISON BETWEEN TREATMENTS IN A REPEATED‐MEASUREMENT DESIGN: ANOVA AND MULTIVARIATE METHODS
Rouanet, H., & Lépine, D. (1970) · British Journal of Mathematical and Statistical Psychology · doi:10.1111/j.2044-8317.1970.tb00440.x · Cited by 198 · see citing works
On the Relation between Change and Initial Value
Blomqvist, N. (1977) · Journal of the American Statistical Association · doi:10.1080/01621459.1977.10479950 · Cited by 165 · see citing works
On the Relation Between Change and Initial Value
Blomqvist, N. (1977) · Journal of the American Statistical Association · doi:10.2307/2286454 · Cited by 92 · see citing works
Statistical Methodology in the Pharmaceutical Sciences
Ziegel, E. R. (1991) · Technometrics · doi:10.1080/00401706.1991.10484820 · Cited by 81 · see citing works
The variability of serum cholesterol measurements: Implications for screening and monitoring
Thompson, S. G., & Pocock, S. J. (1990) · Journal of Clinical Epidemiology · doi:10.1016/0895-4356(90)90238-k · Cited by 64 · see citing works
Self-citationEstimating rates of change in randomized clinical trials
Laird, N. M., & Wang, F. (1990) · Controlled Clinical Trials · doi:10.1016/0197-2456(90)90018-w · Cited by 48 · see citing works
Analyzing laboratory marker changes in AIDS clinical trials.
Dawson, J. D., & Lagakos, S. W. (1991) · PubMed · Cited by 45 · see citing works
Repeated measurements: What is measured and what repeats?
Finney, D. J. (1990) · Statistics in Medicine · doi:10.1002/sim.4780090610 · Cited by 31 · see citing works
The Optimal Spacing of Repeated Measurements
Morrison, D. F. (1970) · Biometrics · doi:10.2307/2529075 · Cited by 23 · see citing works
REPEATED WARNINGS RE REPEATED MEASURES
de Klerk, N. H. (1986) · Australian and New Zealand Journal of Medicine · doi:10.1111/j.1445-5994.1986.tb00001.x · Cited by 16 · see citing works
Development of statistical analysis for single dose bronchodilators
Salsburg, D. S. (1981) · Controlled Clinical Trials · doi:10.1016/0197-2456(81)90020-9 · Cited by 7 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Multilevel linear modelling for FMRI group analysis using Bayesian inference
Woolrich, M. W., Behrens, T. E. J., Beckmann, C. F., Jenkinson, M., & Smith, S. M. (2004) · NeuroImage · doi:10.1016/j.neuroimage.2003.12.023 · Cited by 1,719 · see citing works
General multilevel linear modeling for group analysis in FMRI
Beckmann, C. F., Jenkinson, M., & Smith, S. M. (2003) · NeuroImage · doi:10.1016/s1053-8119(03)00435-x · Cited by 1,464 · see citing works
Listening to Action-related Sentences Activates Fronto-parietal Motor Circuits
Tettamanti, M., Buccino, G., Saccuman, M. C., Gallese, V., Danna, M., Scifo, P., Fazio, F., Rizzolatti, G., Cappa, S. F., & Perani, D. (2005) · Journal of Cognitive Neuroscience · doi:10.1162/0898929053124965 · Cited by 1,239 · see citing works
Dias, S., Sutton, A. J., Ades, A. E., & Welton, N. J. (2013) · Medical Decision Making · doi:10.1177/0272989x12458724 · Cited by 1,207 · see citing works
Subgroup analysis and other (mis)uses of baseline data in clinical trials
Assmann, S. F., Pocock, S. J., Enos, L. E., & Kasten, L. E. (2000) · The Lancet · doi:10.1016/s0140-6736(00)02039-0 · Cited by 1,167 · see citing works
Self-citationLowering blood homocysteine with folic acid based supplements: meta-analysis of randomised trials
Homocysteine Lowering Trialists' Collaboration (1998) · BMJ · doi:10.1136/bmj.316.7135.894 · Cited by 1,085 · see citing works
Pocock, S. J., Assmann, S. E., Enos, L. E., & Kasten, L. E. (2002) · Statistics in Medicine · doi:10.1002/sim.1296 · Cited by 1,077 · see citing works
Self-citationBeyond baseline and follow-up: The case for more T in experiments
McKenzie, D. (2012) · Journal of Development Economics · doi:10.1016/j.jdeveco.2012.01.002 · Cited by 871 · see citing works
Sample Size Estimation: How Many Individuals Should Be Studied?
Eng, J. (2003) · Radiology · doi:10.1148/radiol.2272012051 · Cited by 811 · see citing works
Event‐related beta desynchronization in human subthalamic nucleus correlates with motor performance
Kühn, A. A., Williams, D., Kupsch, A. R., Limousin, P. D., Hariz, M. I., Schneider, G., Yarrow, K., & Brown, P. (2004) · Brain · doi:10.1093/brain/awh106 · Cited by 743 · see citing works
Sample sizes for clinical trials with normal data.
Julious, S. A. (2004) · Statistics in Medicine · doi:10.1002/sim.1783 · Cited by 605 · see citing works
A cultural effect on brain function
Paulesu, E., McCrory, E., Fazio, F., Menoncello, L., Brunswick, N., Cappa, S. F., Cotelli, M., Cossu, G., Corte, F., Lorusso, M., et al. (2000) · Nature Neuroscience · doi:10.1038/71163 · Cited by 602 · see citing works
Vickers, A. J. (2001) · BMC Medical Research Methodology · doi:10.1186/1471-2288-1-6 · Cited by 564 · see citing works
Transdermal oestrogen for treatment of severe postnatal depression
Grégoire, A., Kumar, R., Everitt, B. J., & Studd, J. W. W. (1996) · The Lancet · doi:10.1016/s0140-6736(96)91414-2 · Cited by 559 · see citing works
EEG-Neurofeedback as a Tool to Modulate Cognition and Behavior: A Review Tutorial
Enriquez‐Geppert, S., Huster, R. J., & Herrmann, C. S. (2017) · Frontiers in Human Neuroscience · doi:10.3389/fnhum.2017.00051 · Cited by 526 · see citing works
Chaturvedi, N. (1997) · The Lancet · doi:10.1016/s0140-6736(96)10244-0 · Cited by 526 · see citing works
Chataway, J., Schuerer, N., Alsanousi, A., Chan, D., MacManus, D. G., Hunter, K., Anderson, V. M., Bangham, C. R. M., Clegg, S., Nielsen, C. F., et al. (2014) · The Lancet · doi:10.1016/s0140-6736(13)62242-4 · Cited by 444 · see citing works
Garland, E. L., Manusov, E. G., Froeliger, B., Kelly, A., Williams, J. M., & Howard, M. O. (2014) · Journal of Consulting and Clinical Psychology · doi:10.1037/a0035798 · Cited by 431 · see citing works
RATCLIFFE, J. H., TANIGUCHI, T., GROFF, E. R., & WOOD, J. D. (2011) · Criminology · doi:10.1111/j.1745-9125.2011.00240.x · Cited by 436 · see citing works
Treatment of pseudobulbar affect in ALS with dextromethorphan/quinidine
Brooks, B. R., Thisted, R. A., Appel, S. H., Bradley, W. G., Olney, R. K., Berg, J. E., Pope, L. E., & Smith, R. A. (2004) · Neurology · doi:10.1212/01.wnl.0000142042.50528.2f · Cited by 434 · see citing works
Real versus imagined locomotion: A [18F]-FDG PET-fMRI comparison
la Fougère, C., Zwergal, A., Rominger, A., Förster, S., Fesl, G., Dieterich, M., Brandt, T., Strupp, M. L., Bartenstein, P., & Jahn, K. (2009) · NeuroImage · doi:10.1016/j.neuroimage.2009.12.060 · Cited by 402 · see citing works
Jahn, K., Deutschlander, A. B., Stephan, T., Strupp, M. L., Wiesmann, M., & Brandt, T. (2004) · NeuroImage · doi:10.1016/j.neuroimage.2004.05.017 · Cited by 403 · see citing works
Randomized double-blind study of cyclosporin in chronic ‘idiopathic’ urticaria
Grattan, C. E. H., O’Donnell, B. F., Francis, D. M., Niimi, N., Barlow, R., Seed, P. T., Black, A. K., & Greaves, M. W. (2000) · British Journal of Dermatology · doi:10.1046/j.1365-2133.2000.03664.x · Cited by 409 · see citing works
Penny, W. D., & Holmes, A. J. (2007) · Elsevier eBooks · doi:10.1016/b978-012372560-8/50012-7 · Cited by 406 · see citing works
Vickers, A. J. (2005) · BMC Medical Research Methodology · doi:10.1186/1471-2288-5-35 · Cited by 400 · see citing works
Change from baseline and analysis of covariance revisited
Senn, S. J. (2006) · Statistics in Medicine · doi:10.1002/sim.2682 · Cited by 392 · see citing works
Adjusting for partially missing baseline measurements in randomized trials
White, I. R., & Thompson, S. G. (2005) · Statistics in Medicine · doi:10.1002/sim.1981 · Cited by 378 · see citing works
Dextromethorphan Plus Ultra Low‐Dose Quinidine Reduces Pseudobulbar Affect
Pioro, E. P., Brooks, B. R., Cummings, J. L., Schiffer, R. B., Thisted, R. A., Wynn, D. R., Hepner, A., & Kaye, R. E. (2010) · Annals of Neurology · doi:10.1002/ana.22093 · Cited by 371 · see citing works
Henson, R. N., Price, C. J., Rugg, M. D., Turner, R., & Friston, K. J. (2002) · NeuroImage · doi:10.1006/nimg.2001.0940 · Cited by 356 · see citing works
Variability in fMRI: An Examination of Intersession Differences
McGonigle, D. J., Howseman, A., Athwal, B. S., Friston, K. J., Frackowiak, R. S. J., & Holmes, A. P. (2000) · NeuroImage · doi:10.1006/nimg.2000.0562 · Cited by 351 · see citing works
Henson, R. N. A., Rugg, M., Shallice, T., & Dolan, R. J. (2000) · Journal of Cognitive Neuroscience · doi:10.1162/08989290051137468 · Cited by 365 · see citing works
Functional connectivity networks are disrupted in left temporal lobe epilepsy
Waites, A. B., Briellmann, R. S., Saling, M. M., Abbott, D. F., & Jackson, G. D. (2006) · Annals of Neurology · doi:10.1002/ana.20733 · Cited by 329 · see citing works
Caraceni, A. T., Zecca, E., Bonezzi, C., Arcuri, E., Yayá, R., Maltoni, M. C., Visentin, M., Gorni, G., Martini, C., Tirelli, W., et al. (2004) · Journal of Clinical Oncology · doi:10.1200/jco.2004.08.141 · Cited by 319 · see citing works
Stepped wedge designs could reduce the required sample size in cluster randomized trials
Woertman, W. H., Hoop, E. O., Moerbeek, M., Zuidema, S. U., Gerritsen, D. L., & Teerenstra, S. (2013) · Journal of Clinical Epidemiology · doi:10.1016/j.jclinepi.2013.01.009 · Cited by 300 · see citing works
TONGE, B., BRERETON, A., KIOMALL, M., MACKINNON, A., KING, N., & RINEHART, N. (2006) · Journal of the American Academy of Child & Adolescent Psychiatry · doi:10.1097/01.chi.0000205701.48324.26 · Cited by 298 · see citing works
Solomon, M., Ono, M. Y., Timmer, S. G., & Goodlin‐Jones, B. L. (2008) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-008-0567-5 · Cited by 275 · see citing works
Sample size calculation for stepped wedge and other longitudinal cluster randomised trials
Hooper, R., Teerenstra, S., Hoop, E. O., & Eldridge, S. M. (2016) · Statistics in Medicine · doi:10.1002/sim.7028 · Cited by 261 · see citing works
Aging of human supraspinal locomotor and postural control in fMRI
Zwergal, A., Linn, J., Xiong, G., Brandt, T., Strupp, M. L., & Jahn, K. (2010) · Neurobiology of Aging · doi:10.1016/j.neurobiolaging.2010.09.022 · Cited by 249 · see citing works
Liu, G. F., Lu, K., Mogg, R., Mallick, M., & Mehrotra, D. V. (2009) · Statistics in Medicine · doi:10.1002/sim.3639 · Cited by 254 · see citing works
Functional MRI of galvanic vestibular stimulation with alternating currents at different frequencies
Stephan, T., Deutschlander, A. B., Nolte, A., Schneider, E., Wiesmann, M., Brandt, T., & Dieterich, M. (2005) · NeuroImage · doi:10.1016/j.neuroimage.2005.02.049 · Cited by 244 · see citing works
Mano, Y., Iddrisu, A., Yoshino, Y., & Sonobe, T. (2011) · World Development · doi:10.1016/j.worlddev.2011.09.013 · Cited by 238 · see citing works
Bloom, H. S., Richburg-Hayes, L., & Black, A. R. (2007) · Educational Evaluation and Policy Analysis · doi:10.3102/0162373707299550 · Cited by 237 · see citing works
Egbewale, B. E., Lewis, M., & Sim, J. (2014) · BMC Medical Research Methodology · doi:10.1186/1471-2288-14-49 · Cited by 238 · see citing works
Music therapy for mood disturbance during hospitalization for autologous stem cell transplantation
Cassileth, B. R., Vickers, A. J., & Magill, L. (2003) · Cancer · doi:10.1002/cncr.11842 · Cited by 230 · see citing works
Garrod, R., Mikelsons, C., Paul, E. A., & Wedzicha, J. A. (2000) · American Journal of Respiratory and Critical Care Medicine · doi:10.1164/ajrccm.162.4.9912029 · Cited by 216 · see citing works
To condition or not condition? Analysing ‘change’ in longitudinal randomised controlled trials
Coffman, C. J., Edelman, D. E., & Woolson, R. F. (2016) · BMJ Open · doi:10.1136/bmjopen-2016-013096 · Cited by 212 · see citing works
Stinson, J., McGrath, P. J., HODNETT, E. D., Feldman, B. M., Duffy, C. M., Huber, A. M., Tucker, L. B., Hetherington, C. R., Tse, S. M. L., Spiegel, L. R., et al. (2010) · The Journal of Rheumatology · doi:10.3899/jrheum.091327 · Cited by 209 · see citing works
Chappell, L. C., Seed, P. T., CStat, Kelly, F. J., Briley, A. L., Hunt, B. J., Jones, D. S., Mallet, A. I., & Poston, L. (2002) · American Journal of Obstetrics and Gynecology · doi:10.1067/mob.2002.125735 · Cited by 209 · see citing works
A Primer in Longitudinal Data Analysis
Fitzmaurice, G. M., & Ravichandran, C. T. (2008) · Circulation · doi:10.1161/circulationaha.107.714618 · Cited by 203 · see citing works
Arbane, G., Tropman, D., Jackson, D., & Garrod, R. (2010) · Lung Cancer · doi:10.1016/j.lungcan.2010.04.025 · Cited by 200 · see citing works
Team Incentives and Performance: Evidence from a Retail Chain
Friebel, G., Heinz, M., Krueger, M., & Zubanov, N. (2017) · American Economic Review · doi:10.1257/aer.20160788 · Cited by 199 · see citing works
ANCOVA Versus CHANGE From Baseline in Nonrandomized Studies: The Difference
van Breukelen, G. (2013) · Multivariate Behavioral Research · doi:10.1080/00273171.2013.831743 · Cited by 196 · see citing works
Kurwa, H. A., Yong‐Gee, S. A., Seed, P. T., Markey, A. C., & Barlow, R. (1999) · Journal of the American Academy of Dermatology · doi:10.1016/s0190-9622(99)70114-3 · Cited by 191 · see citing works
Paulesu, E., Sambugaro, E., Torti, T., Danelli, L., Ferri, F., Scialfa, G., Sberna, M., Ruggiero, G. M., Bottini, G., & Sassaroli, S. (2009) · Psychological Medicine · doi:10.1017/s0033291709005649 · Cited by 193 · see citing works
Darlow, B. J. S., Coleman, K., McKinlay, E. M., Donovan, S. J., Beckingsale, L., Gray, B. V., Neser, H., Perry, M., Stanley, J., & Pullon, S. (2015) · BMC Medical Education · doi:10.1186/s12909-015-0385-3 · Cited by 194 · see citing works
El-Nezami, H. S., Polychronaki, N. N., Ma, J., Zhu, H., Ling, W., Salminen, E. K., Juvonen, R. O., Salminen, S. J., Poussa, T., & Mykkänen, H. M. (2006) · The American Journal of Clinical Nutrition · doi:10.1093/ajcn/83.5.1199 · Cited by 184 · see citing works
Acupuncture for Pain and Dysfunction After Neck Dissection: Results of a Randomized Controlled Trial
Pfister, D. G., Cassileth, B. R., Deng, G. E., Yeung, K. S., Lee, J. S., Garrity, D., Cronin, A. M., Lee, N. Y., Kraus, D. H., Shaha, A. R., et al. (2010) · Journal of Clinical Oncology · doi:10.1200/jco.2009.26.9860 · Cited by 184 · see citing works
Chappell, L. C., Gurung, V., Seed, P. T., Chambers, J., Williamson, C., & Thornton, J. (2012) · BMJ · doi:10.1136/bmj.e3799 · Cited by 181 · see citing works
Self‐monitoring in Type 2 diabetes mellitus: a meta‐analysis
Coster, S., Gulliford, M. C., Seed, P. T., Powrie, J., & Swaminathan, R. (2000) · Diabetic Medicine · doi:10.1046/j.1464-5491.2000.00390.x · Cited by 177 · see citing works
Combination of Insulin and Metformin in the Treatment of Type 2 Diabetes
Wulffelé, M. G., Kooy, A., Lehert, P., Bets, D., Ogterop, J. C., van der Burg, B. B., Donker, A. J. M., & Stehouwer, C. D. A. (2002) · Diabetes Care · doi:10.2337/diacare.25.12.2133 · Cited by 174 · see citing works
PANITCH, H. S., Thisted, R. A., Smith, R. A., Wynn, D. R., Wymer, J. P., Achiron, A., Vollmer, T. L., Mandler, R. N., Dietrich, D. W., Fletcher, M., et al. (2006) · Annals of Neurology · doi:10.1002/ana.20828 · Cited by 174 · see citing works
Evaluation of a 12-week home-based walking intervention for breast cancer survivors
Matthews, C. E., Wilcox, S., Hanby, C. L., Ananian, C. D., Heiney, S. P., Gebretsadik, T. S., & Shintani, A. (2006) · Supportive Care in Cancer · doi:10.1007/s00520-006-0122-x · Cited by 172 · see citing works
Striatum forever, despite sequence learning variability: A random effect analysis of PET data
Peigneux, P., Maquet, P., Meulemans, T., Destrebecqz, A., Laureys, S., Degueldre, C., Delfiore, G., Aerts, J. J., Luxen, A., Franck, G., et al. (2000) · Human Brain Mapping · doi:10.1002/1097-0193(200008)10:4 · Cited by 172 · see citing works
Maguire, R., Fox, P. A., McCann, L., Miaskowski, C. A., Kotronoulas, G., Miller, M., Furlong, E., Ream, E., Armes, J., Patiraki, E. I., et al. (2017) · BMJ Open · doi:10.1136/bmjopen-2016-015016 · Cited by 172 · see citing works
Morton, R., Elphick, H., Rigby, A. S., Daw, W., King, D. A., Smith, L., & Everard, M. L. (2016) · Thorax · doi:10.1136/thoraxjnl-2015-208171 · Cited by 169 · see citing works
Ekeberg, O. M., Bautz‐Holter, E., Tveitå, E. K., Juel, N. G., Kvalheim, S., & Brox, J. I. (2009) · BMJ · doi:10.1136/bmj.a3112 · Cited by 163 · see citing works
Interhemispheric Transmission of Visuomotor Information in Humans: fMRI Evidence
Tettamanti, M., Paulesu, E., Scifo, P., Maravita, A., Fazio, F., Perani, D., & Marzi, C. A. (2002) · Journal of Neurophysiology · doi:10.1152/jn.2002.88.2.1051 · Cited by 159 · see citing works
The Functional Anatomy of Inhibition Processes Investigated with the Hayling Task
Collette, F., der Linden, M. V., Delfiore, G., Degueldre, C., Luxen, A., & Salmon, É. (2001) · NeuroImage · doi:10.1006/nimg.2001.0846 · Cited by 162 · see citing works
Tonge, B. J., Brereton, A. V., Kiomall, M. C., Mackinnon, A. J., & Rinehart, N. (2012) · Autism · doi:10.1177/1362361312458186 · Cited by 155 · see citing works
Reconciling after civil conflict increases social capital but decreases individual well-being
Cilliers, J., Dube, O., & Siddiqi, B. (2016) · Science · doi:10.1126/science.aad9682 · Cited by 152 · see citing works
Carayol, M., Ninot, G., Sénesse, P., Bleuse, J., Gourgou, S., Sancho-Garnier, H., Sari, C., Romieu, I., Romieu, G., & Jacot, W. (2019) · BMC Cancer · doi:10.1186/s12885-019-5896-6 · Cited by 150 · see citing works
Murayama, K., Usami, S., & Sakaki, M. (2022) · Psychological Methods · doi:10.1037/met0000330 · Cited by 165 · see citing works
Mhurchú, C. N., Poppitt, S. D., McGill, A., Leahy, F. E., Bennett, D., Lin, R., Ormrod, D. J., Ward, L. C., Strik, C., & Rodgers, A. (2004) · International Journal of Obesity · doi:10.1038/sj.ijo.0802693 · Cited by 149 · see citing works
Brunner, E. J., White, I. R., Thorogood, M., Bristow, A., Curle, D., & Marmot, M. G. (1997) · American Journal of Public Health · doi:10.2105/ajph.87.9.1415 · Cited by 147 · see citing works
Sensory system interactions during simultaneous vestibular and visual stimulation in PET
Deutschlander, A. B., Bense, S., Stephan, T., Schwaiger, M., Brandt, T., & Dieterich, M. (2002) · Human Brain Mapping · doi:10.1002/hbm.10030 · Cited by 141 · see citing works
White, I. R., & Thomas, J. (2005) · Clinical Trials · doi:10.1191/1740774505cn081oa · Cited by 143 · see citing works
Support vector machine learning-based fMRI data group analysis
Wang, Z., Childress, A. R., Wang, J., & Detre, J. A. (2007) · NeuroImage · doi:10.1016/j.neuroimage.2007.03.072 · Cited by 138 · see citing works
Measurement in clinical trials: A neglected issue for statisticians?
Senn, S., & Julious, S. (2009) · Statistics in Medicine · doi:10.1002/sim.3603 · Cited by 136 · see citing works
How many repeated measures in repeated measures designs? Statistical issues for comparative trials
Vickers, A. J. (2003) · BMC Medical Research Methodology · doi:10.1186/1471-2288-3-22 · Cited by 137 · see citing works
Ex ante and ex post effects of hybrid index insurance in Bangladesh
Hill, R. V., Kumar, N., Magnan, N., Makhija, S., de Nicola, F., Spielman, D. J., & Ward, P. S. (2018) · Journal of Development Economics · doi:10.1016/j.jdeveco.2018.09.003 · Cited by 136 · see citing works
A Randomized Controlled Trial of Two Semi-Occluded Vocal Tract Voice Therapy Protocols
Kapsner-Smith, M. R., Hunter, E. J., Kirkham, K., Cox, K. T., & Titze, I. R. (2015) · Journal of Speech Language and Hearing Research · doi:10.1044/2015_jslhr-s-13-0231 · Cited by 135 · see citing works
Neural Correlates for the Acquisition of Natural Language Syntax
Tettamanti, M., Alkadhi, H., Moro, A., Perani, D., Kollias, S., & Weniger, D. (2002) · NeuroImage · doi:10.1006/nimg.2002.1201 · Cited by 136 · see citing works
Hoerger, M. P., Epstein, R. M., Winters, P., Fiscella, K. A., Duberstein, P. R., Gramling, R. E., Butow, P. N., Mohile, S. G., Kaesberg, P. R., Tang, W., et al. (2013) · BMC Cancer · doi:10.1186/1471-2407-13-188 · Cited by 127 · see citing works
van Stuijvenberg, M., Derksen‐Lubsen, G., Steyerberg, E. W., Habbema, J. D. F., & Moll, H. A. (1998) · PEDIATRICS · doi:10.1542/peds.102.5.e51 · Cited by 126 · see citing works
Eating in labour. A randomised controlled trial assessing the risks and benefits
Scrutton, M., Metcalfe, G. A., Lowy, C., Seed, P. T., & O’Sullivan, G. (1999) · Anaesthesia · doi:10.1046/j.1365-2044.1999.00750.x · Cited by 123 · see citing works
Evaluation of Outpatient Geriatric Assessment: A Randomized Multi‐site Trial
Silverman, M., Musa, D., Martin, D. C., Lave, J. R., Adams, J., & Ricci, E. M. (1995) · Journal of the American Geriatrics Society · doi:10.1111/j.1532-5415.1995.tb07041.x · Cited by 122 · see citing works
Postural imbalance and falls in PSP correlate with functional pathology of the thalamus
Zwergal, A., la Fougère, C. J., Lorenzl, S., Rominger, A., Xiong, G., Deutschenbaur, L., Linn, J., KRAFCZYK, S., Dieterich, M., Brandt, T. H., et al. (2011) · Neurology · doi:10.1212/wnl.0b013e318223c79d · Cited by 121 · see citing works
An Evaluation of Isotonic “Sport Drinks” During Labor
Kubli, M., Scrutton, M., Seed, P. T., & Sullivan, G. O. (2002) · Anesthesia & Analgesia · doi:10.1097/00000539-200202000-00033 · Cited by 120 · see citing works
Statistical Power for Nonequivalent Pretest-Posttest Designs
Oakes, J. M., & Feldman, H. A. (2001) · Evaluation Review · doi:10.1177/0193841x0102500101 · Cited by 119 · see citing works
Listing, M., Reißhauer, A., Krohn, M., Voigt, B., Tjahono, G., Becker, J., Klapp, B. F., & Rauchfuß, M. (2009) · Psycho-Oncology · doi:10.1002/pon.1508 · Cited by 119 · see citing works
IL-1β Receptor Antagonist Reduces Inflammation in Hemodialysis Patients
Hung, A. M., Ellis, C. D., Shintani, A., Booker, C., & Ikizler, T. A. (2011) · Journal of the American Society of Nephrology · doi:10.1681/asn.2010070760 · Cited by 117 · see citing works
Alpha calculus in clinical trials: considerations and commentary for the new millennium
Moy�, L. A. (2000) · Statistics in Medicine · doi:10.1002/(sici)1097-0258(20000330)19:6 · Cited by 69 · see citing works
Factors Contributing to Positive Mood during the Menopausal Transition
Dennerstein, L., Lehert, P., Dudley, E., & Guthrie, J. R. (2001) · The Journal of Nervous and Mental Disease · doi:10.1097/00005053-200102000-00003 · Cited by 112 · see citing works
Garland, E. L., Baker, A. K., Larsen, P., Riquino, M. R., Priddy, S. E., Thomas, E., Hanley, A. W., Galbraith, P., Wanner, N., & Nakamura, Y. (2017) · Journal of General Internal Medicine · doi:10.1007/s11606-017-4116-9 · Cited by 109 · see citing works
Risberg, M. A., & Holm, I. (2009) · The American Journal of Sports Medicine · doi:10.1177/0363546509335196 · Cited by 108 · see citing works
Friedlr, K., King, M., Lloyd, M., & Horder, J. (1997) · The Lancet · doi:10.1016/s0140-6736(97)05298-7 · Cited by 108 · see citing works
Hirabayashi, T., & Miyashita, Y. (2005) · Journal of Neuroscience · doi:10.1523/jneurosci.3036-05.2005 · Cited by 107 · see citing works
Standeven, K. F., Ariëns, R. A. S., Whitaker, P., Ashcroft, A. E., Weisel, J. W., & Grant, P. J. (2002) · Diabetes · doi:10.2337/diabetes.51.1.189 · Cited by 106 · see citing works
Nakamura, Y., Lipschitz, D. L., Kuhn, R., Kinney, A. Y., & Donaldson, G. W. (2013) · Journal of Cancer Survivorship · doi:10.1007/s11764-012-0252-8 · Cited by 102 · see citing works
Tice, J. A., Ross, E., Coxson, P. G., Rosenberg, I. H., Weinstein, M. C., Hunink, M. G. M., Goldman, P. A., Williams, L. E., & Goldman, L. (2001) · JAMA · doi:10.1001/jama.286.8.936 · Cited by 101 · see citing works
- Authors
- Frison, L., & Pocock, S. J.
- Affiliations
- London School of Hygiene & Tropical Medicine (GB)
- Venue
- Statistics in Medicine
- Publisher
- Wiley
- Published
- 1992-01
- Volume
- 11
- Issue
- 13
- Pages
- 1685-1704
- ISSN
- 0277-6715 (ISSN-L)
- 1097-0258
- OpenAlex
- W4235700900
- Cited by
- 593
- References
- 17
- Citations by year
- 2026: 14 · 2025: 22 · 2024: 23 · 2023: 18 · 2022: 21 · 2021: 29 · 2020: 24 · 2019: 21 · 2018: 18 · 2017: 22 · 2016: 29 · 2015: 23 · 2014: 21 · 2013: 16 · 2012: 20
- FWCI
- 8.02
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Statistics in Medicine (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods and Bayesian Inference
- Social Sciences › Decision Sciences › Management Science and Operations Research › Optimal Experimental Design Methods
- Keywords
- repeated measures, randomized controlled trials, covariance analysis, compound symmetry, covariance structure, sample size determination, trial design, correlation structure
- MeSH terms
- Analysis of Variance, Clinical Trials as Topic, Data Interpretation, Statistical, Humans, Research Design, Models, Statistical, Randomized Controlled Trials as Topic
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
