S D Walter

Summary

Affiliation: McMaster University
Country: Canada

Publications

  1. doi request reprint Clinical experience may affect clinician compliance with assigned treatment in randomized trials
    Stephen D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, CRL233 Hamilton, Ontario L8N 3Z5, Canada
    J Clin Epidemiol 66:768-74. 2013
  2. pmc Accuracy of p53 codon 72 polymorphism status determined by multiple laboratory methods: a latent class model analysis
    Stephen D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    PLoS ONE 8:e56430. 2013
  3. doi request reprint Treatment effects on patient-important outcomes can be small, even with large effects on surrogate markers
    Stephen D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, HSC 2C16, Hamilton, Ontario L8N 3Z5, Canada
    J Clin Epidemiol 65:940-5. 2012
  4. pmc The impact of clinical data on the evaluation of tibial fracture healing
    Bernadette G Dijkman
    Division of Orthopaedic Surgery, McMaster University, Hamilton, Ontario, Canada
    Trials 12:237. 2011
  5. doi request reprint Optimal allocation of participants for the estimation of selection, preference and treatment effects in the two-stage randomised trial design
    S D Walter
    Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Stat Med 31:1307-22. 2012
  6. doi request reprint Effect of dependent errors in the assessment of diagnostic or screening test accuracy when the reference standard is imperfect
    S D Walter
    Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Stat Med 31:1129-38. 2012
  7. pmc LOST to follow-up Information in Trials (LOST-IT): a protocol on the potential impact
    Elie A Akl
    Department of Medicine, State University of New York at Buffalo, Buffalo, USA
    Trials 10:40. 2009
  8. pmc Subgroup Analysis of Trials Is Rarely Easy (SATIRE): a study protocol for a systematic review to characterize the analysis, reporting, and claim of subgroup effects in randomized trials
    Xin Sun
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada
    Trials 10:101. 2009
  9. pmc Stopping randomized trials early for benefit: a protocol of the Study Of Trial Policy Of Interim Truncation-2 (STOPIT-2)
    Matthias Briel
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada
    Trials 10:49. 2009
  10. pmc Using knowledge brokers to facilitate the uptake of pediatric measurement tools into clinical practice: a before-after intervention study
    Dianne J Russell
    CanChild Centre for Childhood Disability Research, McMaster University, Hamilton, Ontario, Canada
    Implement Sci 5:92. 2010

Detail Information

Publications110 found, 100 shown here

  1. doi request reprint Clinical experience may affect clinician compliance with assigned treatment in randomized trials
    Stephen D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, CRL233 Hamilton, Ontario L8N 3Z5, Canada
    J Clin Epidemiol 66:768-74. 2013
    ..To examine the relationship between clinical experience and clinician compliance with the study protocol in randomized clinical trials...
  2. pmc Accuracy of p53 codon 72 polymorphism status determined by multiple laboratory methods: a latent class model analysis
    Stephen D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    PLoS ONE 8:e56430. 2013
    ..While several methods for genotyping p53 exist, they vary in accuracy and are often discrepant...
  3. doi request reprint Treatment effects on patient-important outcomes can be small, even with large effects on surrogate markers
    Stephen D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, HSC 2C16, Hamilton, Ontario L8N 3Z5, Canada
    J Clin Epidemiol 65:940-5. 2012
    ..We wished to estimate the ultimate effects of treatment when randomized trials have addressed only a surrogate marker, and additional, independent studies evaluate the association between the surrogate and the final outcome...
  4. pmc The impact of clinical data on the evaluation of tibial fracture healing
    Bernadette G Dijkman
    Division of Orthopaedic Surgery, McMaster University, Hamilton, Ontario, Canada
    Trials 12:237. 2011
    ..We explored the effect of adding clinical notes to radiographs in the adjudication process of a feasibility trial of tibial shaft fractures...
  5. doi request reprint Optimal allocation of participants for the estimation of selection, preference and treatment effects in the two-stage randomised trial design
    S D Walter
    Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Stat Med 31:1307-22. 2012
    ..We illustrate the results with trial data comparing alternative clinical management strategies for women with abnormal results on cervical screening...
  6. doi request reprint Effect of dependent errors in the assessment of diagnostic or screening test accuracy when the reference standard is imperfect
    S D Walter
    Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Stat Med 31:1129-38. 2012
    ..We illustrate these ideas through general numerical calculations and an empirical example of screening for breast cancer with magnetic resonance imaging and mammography...
  7. pmc LOST to follow-up Information in Trials (LOST-IT): a protocol on the potential impact
    Elie A Akl
    Department of Medicine, State University of New York at Buffalo, Buffalo, USA
    Trials 10:40. 2009
    ..The secondary objectives are to describe, for published RCTs, (1) the reporting of loss to follow-up information, (2) the analytic methods used for handling loss to follow-up information, and (3) the extent of reported loss to follow-up...
  8. pmc Subgroup Analysis of Trials Is Rarely Easy (SATIRE): a study protocol for a systematic review to characterize the analysis, reporting, and claim of subgroup effects in randomized trials
    Xin Sun
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada
    Trials 10:101. 2009
    ....
  9. pmc Stopping randomized trials early for benefit: a protocol of the Study Of Trial Policy Of Interim Truncation-2 (STOPIT-2)
    Matthias Briel
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada
    Trials 10:49. 2009
    ..The aim of STOPIT-2 is to determine the magnitude and determinants of possible bias introduced by stopping RCTs early for benefit...
  10. pmc Using knowledge brokers to facilitate the uptake of pediatric measurement tools into clinical practice: a before-after intervention study
    Dianne J Russell
    CanChild Centre for Childhood Disability Research, McMaster University, Hamilton, Ontario, Canada
    Implement Sci 5:92. 2010
    ..The KB model evaluated in this study was designed to overcome many of the barriers to research transfer identified in the literature...
  11. pmc Comparing estimates of influenza-associated hospitalization and death among adults with congestive heart failure based on how influenza season is defined
    Carolyn Sandoval
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    BMC Public Health 8:59. 2008
    ..The objective of this study was to compare estimates of influenza-associated risk in a defined clinical population using four different methods of defining the influenza season...
  12. pmc Caregiving process and caregiver burden: conceptual models to guide research and practice
    Parminder Raina
    McMaster University, Department of Clinical Epidemiology and Biostatistics, Hamilton, Ontario, Canada
    BMC Pediatr 4:1. 2004
    ..To understand parents' adaptations to their children's disabilities, the complex nature of stress processes must be accounted for and the constructs and factors that play a role in the caregiving must be considered...
  13. pmc Focus on Function - a randomized controlled trial comparing two rehabilitation interventions for young children with cerebral palsy
    Mary Law
    CanChild Centre for Childhood Disability Research, McMaster University, IAHS Bldg 1400 Main St W, Hamilton, Ontario, L8S 1C7, Canada
    BMC Pediatr 7:31. 2007
    ....
  14. pmc Interval estimation and optimal design for the within-subject coefficient of variation for continuous and binary variables
    Mohamed M Shoukri
    Department of Biostatistics, Epidemiology and Scientific Computing King Faisal Specialist Hospital and Research Centre, P O Box 3354, Riyadh 11211, Saudi Arabia
    BMC Med Res Methodol 6:24. 2006
    ..We investigate sample size requirements for the within-subject coefficient of variation for continuous and binary variables...
  15. pmc Structural equation and log-linear modeling: a comparison of methods in the analysis of a study on caregivers' health
    Bin Zhu
    Centre for Clinical Epidemiology and Community Studies, Sir Mortimer B, Davis Jewish General Hospital, Montreal, Quebec, Canada
    BMC Med Res Methodol 6:49. 2006
    ..In this paper we compare the results in an analysis of determinants of caregivers' health derived from two approaches, a structural equation model and a log-linear model, using the same data set...
  16. pmc Sample size determination for bibliographic retrieval studies
    Xiaomei Yao
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    BMC Med Inform Decis Mak 8:43. 2008
    ....
  17. pmc Optimizing antibiotics in residents of nursing homes: protocol of a randomized trial
    Mark Loeb
    Department of Pathology and Molecular Medicine, McMaster University Hamilton, ON, Canada
    BMC Health Serv Res 2:17. 2002
    ..This proposal describes a randomized trial of diagnostic and therapeutic algorithms to reduce the use of antibiotics in residents of long-term care facilities...
  18. pmc Predictors of inhospital mortality and re-hospitalization in older adults with community-acquired pneumonia: a prospective cohort study
    Binod Neupane
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    BMC Geriatr 10:22. 2010
    ..We aimed to assess the associations of potentially modifiable factors with mortality and re-hospitalization in older adults hospitalized with community-acquired pneumonia...
  19. ncbi request reprint A new preference-based analysis for randomized trials can estimate treatment acceptability and effect in compliant patients
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, HSC 2C16, 1200 Main St West, Hamilton, Ontario L8N 3Z5, Canada
    J Clin Epidemiol 59:685-96. 2006
    ..Development of a new method of analysis to evaluate the acceptability of (or preferences for) the treatments in a randomized trial, and the benefit of treatment among compliers...
  20. doi request reprint A geometric confidence ellipse approach to the estimation of the ratio of two variables
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ont, Canada
    Stat Med 27:5956-74. 2008
    ..The probability of no real solution existing was also evaluated. These ideas are illustrated by a practical example...
  21. pmc Use of latent class models to accommodate inter-laboratory variation in assessing genetic polymorphisms associated with disease risk
    Stephen D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    BMC Genet 9:51. 2008
    ..Possible LCMs are characterised in terms of the number of laboratory measurements available, and if their error rates are assumed to be differential or non-differential by disease status and/or laboratory...
  22. ncbi request reprint Variation in baseline risk as an explanation of heterogeneity in meta-analysis
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Stat Med 16:2883-900. 1997
    ..The methods are illustrated with data from meta-analyses on pre-term delivery and on therapies to lower serum cholesterol...
  23. ncbi request reprint Mammographic screening: case-control studies
    S D Walter
    Clinical Epidemiology and Biostatistics, McMaster University, Health Sciences Centre, Hamilton, Ontario, Canada
    Ann Oncol 14:1190-2. 2003
    ..The case-control design can be used to evaluate the benefit of cancer screening programmes...
  24. ncbi request reprint Effect of exposure misclassification on the mean squared error of population attributable risk and prevented fraction estimates
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ont, Canada
    Stat Med 26:4833-42. 2007
    ..Loss of precision in the AR and PF estimates can be safely ignored only when the exposure measure is very accurate...
  25. ncbi request reprint Effect sizes can be calculated for studies reporting ranges for outcome variables in systematic reviews
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    J Clin Epidemiol 60:849-52. 2007
    ..To develop a method by which studies reporting the ranges (or maxima and minima) of observed outcomes can be included in systematic reviews, along with other studies reporting in the more usual way by using standard deviations (SDs)...
  26. ncbi request reprint The partial area under the summary ROC curve
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Health Sciences Center 2C16, 1200 Main Street West, Hamilton, Ontario, Canada L8N 3Z5
    Stat Med 24:2025-40. 2005
    ..Finally, the partial area lacks a useful symmetry property enjoyed by the full AUC. Although the partial AUC may sometimes have clinical appeal, on balance the use of the full AUC is preferred...
  27. ncbi request reprint Estimation, power and sample size calculations for stochastic cost and effectiveness analysis
    S D Walter
    Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Pharmacoeconomics 25:455-66. 2007
    ..These ideas are illustrated using numerical examples...
  28. ncbi request reprint Studies reporting ROC curves of diagnostic and prediction data can be incorporated into meta-analyses using corresponding odds ratios
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, 1200 Main Street West, HSC 2C16, Hamilton, Ontario, Canada L8N 3Z5
    J Clin Epidemiol 60:530-4. 2007
    ..To develop an approach by which studies describing the accuracy of diagnostic tests or clinical predictions can be combined in a meta-analysis, even though studies may report their results using different summary measures...
  29. ncbi request reprint Pre-trial evaluation of the potential for unblinding in drug trials: a prototype example
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, HSC 2C16, Hamilton, Ontario, Canada L8N 3Z5
    Contemp Clin Trials 26:459-68. 2005
    ..The methods proposed here could easily be adapted to evaluate the results of such experiments...
  30. pmc Statistical issues in the design and analysis of expertise-based randomized clinical trials
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ont, Canada L8N 3Z5
    Stat Med 27:6583-96. 2008
    ..These concepts are illustrated with data taken from a randomized trial of two alternative surgical techniques for tibial fractures...
  31. doi request reprint Uncertainty in the minimum event risk to justify treatment was evaluated
    Stephen D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, HSC 2C16, Hamilton, Ontario, Canada
    J Clin Epidemiol 62:816-24. 2009
    ..To derive expressions for the standard errors (SEs) and coefficients of variation (CV) of the threshold number needed to treat (NNT(t)) and the minimum target event risk for treatment (MERT)...
  32. ncbi request reprint The problem of imperfect reference standards
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
    J Clin Epidemiol 58:649-50. 2005
  33. ncbi request reprint Number needed to treat (NNT): estimation of a measure of clinical benefit
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, Health Sciences Centre 2C16, McMaster University, 1200 Main Street West, Hamilton, Ontario, Canada, L8N 3Z5
    Stat Med 20:3947-62. 2001
    ..Estimators and their variances are obtained for these measures in cross-over or parallel group designs. The ideas are illustrated with data on quality of life in asthma patients...
  34. ncbi request reprint Properties of the summary receiver operating characteristic (SROC) curve for diagnostic test data
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Stat Med 21:1237-56. 2002
    ..The methods are illustrated using data for the Pap smear screening test for cervical cancer, and for three tests for the diagnosis of metastases in cervical cancer patients...
  35. ncbi request reprint Estimating the number needed to treat (NNT) index when the data are subject to error
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Stat Med 20:893-906. 2001
    ..General expressions for the bias are derived, and enumerated for typical scenarios. For many situations, reliability of 80 per cent or more in the observations is required to restrict the bias to tolerable levels...
  36. ncbi request reprint Do larger people have more naevi? Naevus frequency versus naevus density
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada
    Int J Epidemiol 29:1025-30. 2000
    ..In this study, we explored the relationship between the number and the density of naevi in a sample of adolescents...
  37. doi request reprint When should one adjust for measurement error in baseline variables in observational studies?
    Stephen D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, 1200 Main St W, Hamilton, Ontario, Canada
    Biom J 53:28-39. 2011
    ..2-0.3 standard deviation units. These results are illustrated with data from a cohort study of atherosclerosis...
  38. ncbi request reprint Choice of effect measure for epidemiological data
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada L8N 3Z5
    J Clin Epidemiol 53:931-9. 2000
    ..A clear distinction should be maintained between the objectives of data analysis and subsequent risk communication, and different effect measures may be needed for each...
  39. doi request reprint Local estimates of population attributable risk
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, HSC 2C16, Hamilton, Ontario L8N 3Z5, Canada
    J Clin Epidemiol 63:85-93. 2010
    ..Examples include situations where one requires local estimates of PAR for a study subset (e.g., in states or counties within a national study) or if one wishes to apply the findings of an epidemiologic study to another population...
  40. ncbi request reprint Meta-analysis of screening data: a survey of the literature
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada L8N 3Z5
    Stat Med 18:3409-24. 1999
    ..There is considerable potential for meta-analyses of this kind, but improvement in methodological standards will be required to obtain valid conclusions...
  41. ncbi request reprint Meta-analysis of diagnostic tests with imperfect reference standards
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    J Clin Epidemiol 52:943-51. 1999
    ....
  42. ncbi request reprint Association of cutaneous malignant melanoma with intermittent exposure to ultraviolet radiation: results of a case-control study in Ontario, Canada
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Int J Epidemiol 28:418-27. 1999
    ....
  43. ncbi request reprint An analysis of the geographic variation in cancer incidence and its determinants in Ontario
    S D Walter
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario
    Can J Public Health 90:104-8. 1999
    ..A few cancer sites provide limited evidence of regional effects that may warrant further investigation...
  44. ncbi request reprint Incidence of and risk factors for ventilator-associated pneumonia in critically ill patients
    D J Cook
    McMaster University, Hamilton, Ontario, Canada
    Ann Intern Med 129:433-40. 1998
    ..Understanding the risk factors for ventilator-associated pneumonia can help to assess prognosis and devise and test preventive strategies...
  45. ncbi request reprint Rasch analysis of the Gross Motor Function Measure: validating the assumptions of the Rasch model to create an interval-level measure
    Lisa M Avery
    CanChild Centre for Childhood Disability Research, Institute for Applied Health Sciences, McMaster University, Hamilton, ON, Canada
    Arch Phys Med Rehabil 84:697-705. 2003
    ..To describe the Rasch analysis of the Gross Motor Function Measure (GMFM-88) and to demonstrate how the assumptions of unidimensionality, sample-free measurement, and test-free measurement were validated to create an interval level measure...
  46. ncbi request reprint A comparison of model-building strategies for lower respiratory tract infection in long-term care
    M Loeb
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    J Clin Epidemiol 52:1239-48. 1999
    ..The data-derived and consensus models showed the highest discriminative ability while the linear judgment model showed inferior performance...
  47. pmc Nursing home residents and Enterobacteriaceae resistant to third-generation cephalosporins
    Carolyn Sandoval
    McMaster University, Hamilton, Ontario, Canada
    Emerg Infect Dis 10:1050-5. 2004
    ..2 to 13.6) and log percentage of residents using gastrostomy tubes within the nursing home (adjusted OR 3.9, 95% CI 1.3 to 12.0) were associated with having a clinical isolate resistant to third-generation cephalosporins...
  48. ncbi request reprint Pneumonia and lower respiratory infections in nursing home residents: predictors of hospitalization and mortality
    Soo B Chan Carusone
    Departments of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    J Am Geriatr Soc 55:414-9. 2007
    ..To compare predictors of hospitalization and death in nursing home residents with pneumonia and other lower respiratory infections (LRIs)...
  49. pmc Need for expertise based randomised controlled trials
    P J Devereaux
    Department of Clinical Epidemiology and Biostatistics, McMaster University, 1200 Main Street, West Hamilton ON, Canada L8N 3Z5
    BMJ 330:88. 2005
  50. doi request reprint Longitudinal measurements of oxygen consumption in growing infants during the first weeks after birth: old data revisited
    J C Sinclair
    Department of Pediatrics, McMaster University, Hamilton, Ont, Canada
    Neonatology 103:224-32. 2013
    ..In a study conducted in 1966-1969, longitudinal measurements were made of the metabolic rate in growing infants. Statistical methods for analyzing longitudinal data weren't readily accessible at that time...
  51. ncbi request reprint Relation of distribution- and anchor-based approaches in interpretation of changes in health-related quality of life
    G R Norman
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Med Care 39:1039-47. 2001
    ....
  52. pmc The attributable mortality and length of intensive care unit stay of clinically important gastrointestinal bleeding in critically ill patients
    D J Cook
    Department of Medicine, McMaster University, Hamilton, Ontario, Canada
    Crit Care 5:368-75. 2001
    ..To estimate the mortality and length of stay in the intensive care unit (ICU) attributable to clinically important gastrointestinal bleeding in mechanically ventilated critically ill patients...
  53. pmc Use of both Short Musculoskeletal Function Assessment questionnaire and Short Form-36 among tibial-fracture patients was redundant
    Jason W Busse
    Institute for Work and Health, 481 University Avenue, Toronto, Ontario, Canada
    J Clin Epidemiol 62:1210-7. 2009
    ..To compare the Short Musculoskeletal Function Assessment Dysfunction Index (SMFA DI) and the Short Form-36 Physical Component Summary (SF-36 PCS) scores among patients undergoing operative management of tibial fractures...
  54. ncbi request reprint An opportunity cost approach to sample size calculation in cost-effectiveness analysis
    A Gafni
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Health Econ 17:99-107. 2008
    ..We believe that the additional data requirements represent a small price to pay for being able to perform an analysis consistent with both concept of opportunity cost and the problem faced by decision makers...
  55. ncbi request reprint Development and testing of formal protocols for oxygen prescribing
    G H Guyatt
    Department of Clinical Epidemiology and Biostatistics and Department of Medicine, McMaster University, Hamilton, Ontario, Canada
    Am J Respir Crit Care Med 163:942-6. 2001
    ..27 (95% CI -0.18 to 0.72). In conclusion, standardizing tests for the assessment of LTOT is important. We describe simple hospital and simulated home tests that are reproducible, easy to carry out, and correlate well with each other...
  56. ncbi request reprint Operation Everest II: oxygen transport during exercise at extreme simulated altitude
    J R Sutton
    Department of Medicine, McMaster University, Hamilton, Ontario, Canada
    J Appl Physiol 64:1309-21. 1988
    ..These findings suggest that although glycogenolysis may be accentuated at low work loads, it may not be maximally activated at exhaustion...
  57. ncbi request reprint The health and well-being of caregivers of children with cerebral palsy
    Parminder Raina
    Department of Clinical Epidemiology and Biostatistics, McMaster Evidence based Practice Centre, Hamilton, ON, Canada
    Pediatrics 115:e626-36. 2005
    ..The primary objective of the current study was to examine, within a single theory-based multidimensional model, the determinants of physical and psychological health of adult caregivers of children with CP...
  58. doi request reprint Development and validation of item sets to improve efficiency of administration of the 66-item Gross Motor Function Measure in children with cerebral palsy
    Dianne J Russell
    School of Rehabilitation Science, McMaster University, Hamilton, ON, Canada
    Dev Med Child Neurol 52:e48-54. 2010
    ....
  59. doi request reprint Surgical mask vs N95 respirator for preventing influenza among health care workers: a randomized trial
    Mark Loeb
    Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
    JAMA 302:1865-71. 2009
    ..Given the likelihood that N95 respirators will be in short supply during a pandemic and not available in many countries, knowing the effectiveness of the surgical mask is of public health importance...
  60. pmc Resolving controversies in hip fracture care: the need for large collaborative trials in hip fractures
    Mohit Bhandari
    Division of Orthopaedic Surgery, Department of Surgery, McMaster University, Hamilton, Ontario, Canada
    J Orthop Trauma 23:479-84. 2009
    ..This manuscript will describe the need, the information, the organization, and the accomplishments to date of the International Hip Fracture Research Collaborative...
  61. doi request reprint Radiographs of hip fractures were digitally altered to mask surgeons to the type of implant without compromising the reliability of quality ratings or making the rating process more difficult
    Paul J Karanicolas
    Department of Surgery, The University of Western Ontario, University Hospital, Room C8 114, 339 Windermere Rd, London, Ontario N6A 5A5, Canada
    J Clin Epidemiol 62:214-223.e1. 2009
    ..To devise and test techniques to blind outcome assessors in trials of hip fracture fixation...
  62. pmc Stop orders to reduce inappropriate urinary catheterization in hospitalized patients: a randomized controlled trial
    Mark Loeb
    Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
    J Gen Intern Med 23:816-20. 2008
    ..Hospitalized patients frequently have urinary catheters inserted for inappropriate reasons. This can lead to urinary tract infections and other complications...
  63. doi request reprint Environmental risk factors for community-acquired pneumonia hospitalization in older adults
    Mark Loeb
    Departments of Pathology and Molecular Medicine, McMaster University, MDCL 3200, 1200 Main St W, Hamilton, ON L8N 3Z5, Canada
    J Am Geriatr Soc 57:1036-40. 2009
    ..To investigate the risk of hospitalization for pneumonia in older adults in relation to biophysical environmental factors...
  64. doi request reprint Blinding of outcomes in trials of orthopaedic trauma: an opportunity to enhance the validity of clinical trials
    Paul J Karanicolas
    Department of Clinical Epidemiology and Biostatistics, McMaster University, 1200 Main Street West, Hamilton, ON L8N 3Z5, Canada
    J Bone Joint Surg Am 90:1026-33. 2008
    ..Trials of surgical interventions present blinding challenges not seen in drug trials. How often orthopaedic trauma investigators undertake blinding, and the frequency with which they could potentially utilize blinding, remains uncertain...
  65. pmc Study to prospectively evaluate reamed intramedually nails in patients with tibial fractures (S.P.R.I.N.T.): study rationale and design
    Mohit Bhandari
    SPRINT Methods Center, Department of Clinical Epidemiology and Biostatistics, 1200 Main Street West, Room 2C9 Hamilton, Ontario, Canada
    BMC Musculoskelet Disord 9:91. 2008
    ....
  66. ncbi request reprint Stability and decline in gross motor function among children and youth with cerebral palsy aged 2 to 21 years
    Steven E Hanna
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Dev Med Child Neurol 51:295-302. 2009
    ..7, 7.8, and 6.4 GMFM-66 points, in Levels III, IV, and V respectively, as these adolescents became young adults. We show that these declines are clinically significant...
  67. pmc Optimal search strategies for retrieving scientifically strong studies of treatment from Medline: analytical survey
    R Brian Haynes
    Health Information Research Unit, McMaster University, Hamilton, ON, Canada L8N 3Z5
    BMJ 330:1179. 2005
    ..To develop and test optimal Medline search strategies for retrieving sound clinical studies on prevention or treatment of health disorders...
  68. ncbi request reprint Development of hand function among children with cerebral palsy: growth curve analysis for ages 16 to 70 months
    Steven E Hanna
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Dev Med Child Neurol 45:448-55. 2003
    ..However, there is substantial interindividual variation. Distribution of CP and severity of impairments were significant predictors of development. Results are discussed in terms of their clinical implications...
  69. pmc Randomized trial of reamed and unreamed intramedullary nailing of tibial shaft fractures
    Mohit Bhandari
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada
    J Bone Joint Surg Am 90:2567-78. 2008
    ..Previous small trials have left the evidence for either approach inconclusive. We compared reamed and unreamed intramedullary nailing with regard to the rates of reoperations and complications in patients with tibial shaft fractures...
  70. ncbi request reprint Effect of a clinical pathway to reduce hospitalizations in nursing home residents with pneumonia: a randomized controlled trial
    Mark Loeb
    Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
    JAMA 295:2503-10. 2006
    ..Nursing home residents with pneumonia are frequently hospitalized. Such transfers may be associated with multiple hazards of hospitalization as well as economic costs...
  71. pmc McMaster PLUS: a cluster randomized clinical trial of an intervention to accelerate clinical use of evidence-based information from digital libraries
    R Brian Haynes
    McMaster University, Epidemiology and Biostatistics, McMaster Health Sciences Centre, 1200 Main St West, Rm 2C10b, Hamilton, Ontario, Canada
    J Am Med Inform Assoc 13:593-600. 2006
    ..Physicians have difficulty keeping up with new evidence from medical research...
  72. ncbi request reprint Prognosis for gross motor function in cerebral palsy: creation of motor development curves
    Peter L Rosenbaum
    Department of Pediatrics, School of Rehabilitation Science, CanChild Centre for Childhood Disability Research, McMaster University, Hamilton, Ontario, Canada, L8S 1C7
    JAMA 288:1357-63. 2002
    ..Lack of a valid classification of severity of cerebral palsy and the absence of longitudinal data on which to base an opinion have made it difficult to consider prognostic issues accurately...
  73. ncbi request reprint Interobserver reliability of radiologists' interpretations of mobile chest radiographs for nursing home-acquired pneumonia
    Mark B Loeb
    Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
    J Am Med Dir Assoc 7:416-9. 2006
    ..To determine the interobserver reliability of radiologists' interpretations of mobile chest radiographs for nursing home-acquired pneumonia...
  74. pmc A systematic review and meta-analysis of studies comparing mortality rates of private for-profit and private not-for-profit hospitals
    P J Devereaux
    Department of Medicine, McMaster University, Hamilton, Ont
    CMAJ 166:1399-406. 2002
    ..To inform this debate, we undertook a systematic review and meta-analysis of studies comparing the mortality rates of private for-profit hospitals and those of private not-for-profit hospitals...
  75. pmc Effect of a multifaceted intervention on number of antimicrobial prescriptions for suspected urinary tract infections in residents of nursing homes: cluster randomised controlled trial
    Mark Loeb
    Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
    BMJ 331:669. 2005
    ..To assess whether a multifaceted intervention can reduce the number of prescriptions for antimicrobials for suspected urinary tract infections in residents of nursing homes...
  76. doi request reprint Effect of influenza vaccination of children on infection rates in Hutterite communities: a randomized trial
    Mark Loeb
    Department of Pathology and Molecular Medicine, McMaster University, 1200 Main St W, Hamilton, ON, L8N 3Z5 Canada
    JAMA 303:943-50. 2010
    ..Children and adolescents appear to play an important role in the transmission of influenza. Selectively vaccinating youngsters against influenza may interrupt virus transmission and protect those not immunized...
  77. pmc SARS among critical care nurses, Toronto
    Mark Loeb
    Department of Pathology and Molecualr Medicine, McMaster University, Hamilton, Ontario, Canada
    Emerg Infect Dis 10:251-5. 2004
    ..Risk was lower with consistent use of a N95 mask than with consistent use of a surgical mask. We conclude that activities related to intubation increase SARS risk and use of a mask (particularly a N95 mask) is protective...
  78. doi request reprint Community controls were preferred to hospital controls in a case-control study where the cases are derived from the hospital
    Binod Neupane
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    J Clin Epidemiol 63:926-31. 2010
    ..For hospital cases, we examined how inferences drawn from a case-control study can differ by choice of hospital- vs. community-based controls...
  79. ncbi request reprint Risk factors for resistance to antimicrobial agents among nursing home residents
    Mark B Loeb
    Department of Pathology and Molecular Medicine, McMaster University and Hamilton Regional Laboratory Program, Hamilton, Ontario, Canada
    Am J Epidemiol 157:40-7. 2003
    ..08, 95% CI: 1.04, 1.11), respectively. These findings suggest that increased staffing, more hand-washing sinks, and use of antimicrobial soap may reduce resistance to antimicrobial agents in long-term care facilities...
  80. pmc Payments for care at private for-profit and private not-for-profit hospitals: a systematic review and meta-analysis
    P J Devereaux
    Department of Medicine, McMaster University, Hamilton
    CMAJ 170:1817-24. 2004
    ....
  81. ncbi request reprint A geometric confidence ellipse approach to the estimation of the ratio of two variables. Statistics in Medicine 2008; 27:5956-5974
    S D Walter
    McMaster University, Hamilton, Ont, Canada
    Stat Med 28:2723. 2009
    ..Dr Kaelin has offered to make available an Excel spreadsheet that will carry out the calculations for the method described in this paper. It is available to interested readers by contacting him at Etienne.Kaelin@pmintl.com...
  82. ncbi request reprint Improved scaling of the gross motor function measure for children with cerebral palsy: evidence of reliability and validity
    D J Russell
    CanChild, Centre for Childhood Disability Research, Room 408, Institute for Applied Health Sciences, McMaster University, 1400 Main St W, Hamilton, Ontario, Canada
    Phys Ther 80:873-85. 2000
    ..This study examined the reliability, validity, and responsiveness to change of measurements obtained with a 66-item version of the Gross Motor Function Measure (GMFM-66) developed using Rasch analysis...
  83. doi request reprint Evaluating agreement: conducting a reliability study
    Paul J Karanicolas
    Department of Clinical Epidemiology and Biostatistics, McMaster University, 293 Wellington Street North, Suite 110, Hamilton, ON L8L 2X2, Canada
    J Bone Joint Surg Am 91:99-106. 2009
    ..Readers interested in critically appraising reliability studies or in developing their own reliability studies may find this review helpful...
  84. ncbi request reprint The health of primary caregivers of children with cerebral palsy: how does it compare with that of other Canadian caregivers?
    Jamie C Brehaut
    Clinical Epidemiology Unit, Ottawa Health Research Institute, Ottawa Hospital, Ottawa, Ontario, Canada
    Pediatrics 114:e182-91. 2004
    ..The goal of this study was to compare the physical and psychologic health of CGs of children with cerebral palsy (CP) with that of the general population of CGs...
  85. pmc Risk of hospitalization during influenza season among a cohort of patients with congestive heart failure
    C Sandoval
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada
    Epidemiol Infect 135:574-82. 2007
    ..98-1.24, P=0.11). Patients with CHF have a greater risk of hospitalization during the influenza season than in the non-influenza season, supporting the current belief that patients with CHF should be regarded as a high-risk group...
  86. ncbi request reprint Developing common metrics of mechanical exposures across aetiological studies of low back pain in working populations for use in meta-analysis
    L E Griffith
    Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada
    Occup Environ Med 65:467-81. 2008
    ..We aimed to develop common metrics to apply in the translation of literature-based workplace mechanical exposures for use in meta-analyses, and to test the metrics' measurement properties...
  87. ncbi request reprint Mortality predictions in the intensive care unit: comparing physicians with scoring systems
    Tasnim Sinuff
    Department of Critical Care Medicine, Sunnybrook and Women s College Health Sciences Centre, Toronto, Ontario, Canada
    Crit Care Med 34:878-85. 2006
    ..Our systematic review compared the accuracy of ICU physicians' and scoring system predictions of ICU or hospital mortality of critically ill adults...
  88. ncbi request reprint Stability of the gross motor function classification system
    Robert J Palisano
    Program in Policy Decision making, McMaster University, Hamilton, Ontario, Canada
    Dev Med Child Neurol 48:424-8. 2006
    ..There was a tendency for children younger than 6 years who were reclassified to be done so to a lower level of ability. The results provide evidence of stability of the GMFCS...
  89. ncbi request reprint Facility-level correlates of antimicrobial use in nursing homes
    Mark Loeb
    Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
    Infect Control Hosp Epidemiol 25:173-6. 2004
    ....
  90. ncbi request reprint Low-back pain definitions in occupational studies were categorized for a meta-analysis using Delphi consensus methods
    Lauren E Griffith
    Program in Occupational Health and Environmental Medicine, McMaster University, HSC 3H57, Hamilton, Ontario, Canada L8N 3A5
    J Clin Epidemiol 60:625-33. 2007
    ..To determine which literature-based definitions of low back pain (LBP) could be combined to produce sufficiently similar sets for use in a meta-analysis...
  91. ncbi request reprint DNR directives are established early in mechanically ventilated intensive care unit patients
    Tasnim Sinuff
    Department of Medicine, McMaster University Health Sciences Center, Room 2C11, 1200 Main Street West, Hamilton, Ontario L8N 3Z5, Canada
    Can J Anaesth 51:1034-41. 2004
    ..Our objective was to study the rate of establishing do-not-resuscitate (DNR) directives, determinants, and outcomes of those directives for mechanically ventilated patients...
  92. doi request reprint Evaluating the benefit of event adjudication of cardiovascular outcomes in large simple RCTs
    Janice Pogue
    Department of Medicine, McMaster University and Population Health Research Institute of McMaster University, Hamilton, ON, Canada
    Clin Trials 6:239-51. 2009
    ..We conducted a meta-analysis of a series of cardiovascular outcomes trials and estimated the effect of adjudication on treatment estimates and on the number of outcomes included the trials...
  93. ncbi request reprint Effect of environmental setting on mobility methods of children with cerebral palsy
    Robert J Palisano
    Drexel University, Programs in Rehabilitation Sciences, Philadelphia, PA 19102 1192, USA
    Dev Med Child Neurol 45:113-20. 2003
    ..For children who do not walk, attention should be given to the needs of caregivers and factors that are important for successful powered mobility...
  94. ncbi request reprint Is NNT now the number needed to traumatize?
    Stephen D Walter
    J Clin Epidemiol 58:1075-6. 2005
  95. ncbi request reprint Vasopressin or epinephrine for out-of-hospital cardiac arrest
    Peter C Wyer
    Emergency Medicine Residency Program, New York Presbyterian Hospital, New York, NY, USA
    Ann Emerg Med 48:86-97. 2006
    ..We performed an evidence-based emergency medicine review of evidence comparing vasopressin to epinephrine in structured cardiac arrest protocols...
  96. ncbi request reprint New methods give better estimates of changes in diagnostic accuracy when prior information is provided
    Les Irwig
    Screening and Test Evaluation Program, School of Public Health, Building A 27, University of Sydney, New South Wales 2006, Australia
    J Clin Epidemiol 59:299-307. 2006
    ..We propose comparing the combined accuracy of prior information and a test read (i) with or (ii) without knowledge of prior information. Analysis methods include simple decision rules and logistic regression...
  97. ncbi request reprint Randomized controlled trial of human papillomavirus testing versus Pap cytology in the primary screening for cervical cancer precursors: design, methods and preliminary accrual results of the Canadian cervical cancer screening trial (CCCaST)
    Marie Helene Mayrand
    Division of Cancer Epidemiology, Department of Oncology, McGill University, and Département de Microbiologie Infectiologie, Hôpital Notre Dame du Centre Hospitalier Universitaire de l Université de Montréal, QC, Canada
    Int J Cancer 119:615-23. 2006
    ..Because of its design, CCCaST will provide sound evidence for formulating cervical cancer screening strategies...
  98. pmc Three day versus five day treatment with amoxicillin for non-severe pneumonia in young children: a multicentre randomised controlled trial
    Girdhar Agarwal
    BMJ 328:791. 2004
    ..To assess the efficacy of three days versus five days of treatment with oral amoxicillin for curing non-severe pneumonia in children...
  99. ncbi request reprint Intra-class correlation estimates for assessment of vitamin A intake in children
    Girdhar G Agarwal
    Department of Statistics, Lucknow University, Lucknow, India
    J Health Popul Nutr 23:66-73. 2005
    ..014 to 0.45. These estimates may provide useful information for the design of epidemiological studies in which the sampled (or allocated) units range in size from households to large administrative zones...
  100. ncbi request reprint Limb distribution, motor impairment, and functional classification of cerebral palsy
    Jan Willem Gorter
    Rehabilitation Centre De Hoogstraat, Utrecht, The Netherlands
    Dev Med Child Neurol 46:461-7. 2004
    ..Although classification of CP by impairment level is useful for clinical and epidemiological purposes, the value of these subgroups as an indicator of mobility is limited in comparison with the classification of severity with the GMFCS...
  101. ncbi request reprint Adjustment for baseline measurement error in randomized controlled trials induces bias
    Siew F Chan
    Screening and Test Evaluation Program STEP, School of Public Health, The University of Sydney, Edward Ford Building, A27, Sydney, NSW 2006, Australia
    Control Clin Trials 25:408-16. 2004
    ..It is underestimated when the control group has a smaller baseline mean...