Skip to main content

Main menu

  • Home
  • COVID-19
    • Articles & podcasts
    • Blog posts
    • Collection
    • News
  • Content
    • Current issue
    • Past issues
    • Early releases
    • Collections
    • Sections
    • Blog
    • Infographics & illustrations
    • Podcasts
    • Classified ads
  • Authors
    • Overview for authors
    • Submission guidelines
    • Submit a manuscript
    • Forms
    • Editorial process
    • Editorial policies
    • Peer review process
    • Publication fees
    • Reprint requests
  • CMA Members
    • Overview for members
    • Earn CPD Credits
    • Print copies of CMAJ
    • Career Ad Discount
  • Subscribers
    • General information
    • View prices
  • Alerts
    • Email alerts
    • RSS
  • JAMC
    • À propos
    • Numéro en cours
    • Archives
    • Sections
    • Abonnement
    • Alertes
  • CMAJ JOURNALS
    • CMAJ Open
    • CJS
    • JAMC
    • JPN

User menu

Search

  • Advanced search
CMAJ
  • CMAJ JOURNALS
    • CMAJ Open
    • CJS
    • JAMC
    • JPN
CMAJ

Advanced Search

  • Home
  • COVID-19
    • Articles & podcasts
    • Blog posts
    • Collection
    • News
  • Content
    • Current issue
    • Past issues
    • Early releases
    • Collections
    • Sections
    • Blog
    • Infographics & illustrations
    • Podcasts
    • Classified ads
  • Authors
    • Overview for authors
    • Submission guidelines
    • Submit a manuscript
    • Forms
    • Editorial process
    • Editorial policies
    • Peer review process
    • Publication fees
    • Reprint requests
  • CMA Members
    • Overview for members
    • Earn CPD Credits
    • Print copies of CMAJ
    • Career Ad Discount
  • Subscribers
    • General information
    • View prices
  • Alerts
    • Email alerts
    • RSS
  • JAMC
    • À propos
    • Numéro en cours
    • Archives
    • Sections
    • Abonnement
    • Alertes
  • Visit CMAJ on Facebook
  • Follow CMAJ on Twitter
  • Follow CMAJ on Pinterest
  • Follow CMAJ on Youtube
  • Follow CMAJ on Instagram
Research article

Impact of specialist follow-up in outpatients with congestive heart failure

Justin A. Ezekowitz, Carl van Walraven, Finlay A. McAlister, Paul W. Armstrong and Padma Kaul
CMAJ January 18, 2005 172 (2) 189-194; DOI: https://doi.org/10.1503/cmaj.1032017
Justin A. Ezekowitz
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Carl van Walraven
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Finlay A. McAlister
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Paul W. Armstrong
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Padma Kaul
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Figures & Tables
  • Responses
  • Metrics
  • PDF
Loading
Submit a Response to This Article
Compose Response

More information about text formats

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
References
Author Information
First or given name, e.g. 'Peter'.
Your last, or family, name, e.g. 'MacMoody'.
Your email address, e.g. higgs-boson@gmail.com
Your role and/or occupation, e.g. 'Orthopedic Surgeon'. Minimum 7 characters.
Your organization or institution (if applicable), e.g. 'Royal Free Hospital'. Minimum 12 characters.
Your organization, institution's or residential address.
Statement of Competing Interests

Vertical Tabs

Jump to comment:

  • Response
    Justin A Ezekowitz
    Posted on: 22 March 2005
  • Impact of Specialist Follow-up in outpatients with heart failure
    Murray M Finkelstein
    Posted on: 07 February 2005
  • Posted on: (22 March 2005)
    Response
    • Justin A Ezekowitz

    Dear CMAJ,

    We thank Dr. Finkelstein for his letter. Dr. Finkelstein is appropriately concerned about the inclusion of post-event outcomes in the regression model. Such an incident results in biased associations – namely, one being unable to determine if the predictive factor resulted in the event or if the event resulted in the predictive factor. This has been called “survivor-treatment selection bias”(1) or,...

    Show More

    Dear CMAJ,

    We thank Dr. Finkelstein for his letter. Dr. Finkelstein is appropriately concerned about the inclusion of post-event outcomes in the regression model. Such an incident results in biased associations – namely, one being unable to determine if the predictive factor resulted in the event or if the event resulted in the predictive factor. This has been called “survivor-treatment selection bias”(1) or, more generically, “time-dependent bias” and is relatively common even in highly cited medical journals. In a recent systematic review, we found that 18.6% (95% CI 15.8 to 21.8%) of studies with a survival analysis contained a time- dependent factor and that 40.9% [32.3 to 50.0%] of these studies were susceptible to time-dependent bias. (1)

    However, we strongly disagree that our Cox model is done incorrectly, as it corrects for this bias. As we state in the methods section, we adjust for the appropriate time-dependent variables and have a variable expressing ‘time spent in hospital up to that time’. (3) The results section summarizes the findings. The phrase ‘within 1 year after discharge’ stated in the results section refers to the censoring time that we used for all analyses in the study. We do not use ‘future information’ as stated by Dr. Finkelstein, and our methodology is robust.

    We state clearly in our Methods section that we performed a sensitivity analysis using all outpatient visits rather than cardiovascular visits to define our groups; however, this analysis was truncated by the journal due to space limitations. Using the same variables as in Table 3 but using all visits rather than cardiovascular visits, we found similar results: compared to those without any outpatient visits, patients seen by a family physician (OR 0.80 [95%CI 0.64 to 0.96]) or a specialist and family physician (OR 0.48 [95%CI 0.40 to 0.58]) had lower mortality rates. Furthermore, similar results were obtained with the Cox model using all visits instead of cardiovascular visits: seeing a specialist (HR 0.95 [95%CI 0.94 to 0.96]) was associated with lower mortality.

    Regards,

    Justin A. Ezekowitz, MBBCh MSc Carl Van Walraven, MD MSc Finlay A. McAlister, MD MSc Paul W. Armstrong, MD Padma Kaul, PhD

    1. Glesby MJ, Hoover DR. Survivor treatment selection bias in observational studies: examples from the AIDS literature Ann Intern Med 1996;124:999–1005.

    2. van Walraven C, Davis D, Forster AJ, Wells GA. Time-dependent bias was common in survival analyses published in leading clinical journals. Journal of Clinical Epidemiology 2004; 57: 672-680.

    3. Ezekowitz JA, van Walraven C, McAlister FA, Armstrong PA, Kaul P. Impact of specialist follow-up in outpatients with congestive heart failure. CMAJ 2005;172(2):189-94.

    Conflict of Interest:

    None declared

    Show Less
    Competing Interests: None declared.
  • Posted on: (7 February 2005)
    Impact of Specialist Follow-up in outpatients with heart failure
    • Murray M Finkelstein

    Ezekowitz and colleagues have concluded that patients with congestive heart failure followed by specialists and Family Physicians (FP) have better survival than patients followed by FPs alone. Their analysis is, however, not internally consistent. In the methods section they state, quite appropriately, that "a time dependent analysis is essential when examining the effect of physician follow-up because patients' outcomes...

    Show More

    Ezekowitz and colleagues have concluded that patients with congestive heart failure followed by specialists and Family Physicians (FP) have better survival than patients followed by FPs alone. Their analysis is, however, not internally consistent. In the methods section they state, quite appropriately, that "a time dependent analysis is essential when examining the effect of physician follow-up because patients' outcomes can determine their exposure". Nevertheless, apart from a brief paragraph at the end of the results section, all of their findings (Tables 2, 3, and Figure 1) are presented in terms of an inappropriate time-independent analysis which ignores any change in the provision of care during follow- up.

    All patients, at the moment of discharge, will have had no cardiovascular follow-up, and they will remain in that category until the first physician visit, at which time their status will change. Should that visit be to an FP, they will, at that time, move into the FP only category. Should they subsequently visit a specialist, they will move from the FP only to the FP and specialist category. From a methodological point of view, they will leave behind the days at risk they experienced while in each of the preceding categories. A time dependent Cox regression will assign them to the appropriate category in the risk set formed at the time of each death in the cohort. Neither the log-rank analysis of Figure 1, nor the multiple logistic regression analysis of Table 3, make this correct comparison.

    It is also not clear that the Time dependent Cox analysis mentioned in the last paragraph of the results section has been done correctly. The authors state that the model was adjusted for "cumulative days spent in hospital within 1 year after discharge". In a Cox analysis, one compares the characteristics of subjects who die with the characteristics of those subjects still alive at the time of death. The relevant variable, would then be time spent in hospital UP TO THAT TIME. Use of cumulative days within 1 year of discharge requires the use of FUTURE INFORMATION. This is logically untenable.

    I conclude that the authors results cannot be accepted at face value because their methodology was not appropriate for their study design. I would encourage them to compute the appropriate time dependent models to answer this important question about management of congestive heart failure.

    Sincerely,

    Murray Finkelstein PhD MDCM CCFP Family Medicine Centre Mt Sinai Hospital

    Conflict of Interest:

    None declared

    Show Less
    Competing Interests: None declared.
PreviousNext
Back to top

In this issue

Canadian Medical Association Journal: 172 (2)
CMAJ
Vol. 172, Issue 2
18 Jan 2005
  • Table of Contents
  • Index by author

Article tools

Respond to this article
Print
Download PDF
Article Alerts
To sign up for email alerts or to access your current email alerts, enter your email address below:
Email Article

Thank you for your interest in spreading the word on CMAJ.

NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

Enter multiple addresses on separate lines or separate them with commas.
Impact of specialist follow-up in outpatients with congestive heart failure
(Your Name) has sent you a message from CMAJ
(Your Name) thought you would like to see the CMAJ web site.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Impact of specialist follow-up in outpatients with congestive heart failure
Justin A. Ezekowitz, Carl van Walraven, Finlay A. McAlister, Paul W. Armstrong, Padma Kaul
CMAJ Jan 2005, 172 (2) 189-194; DOI: 10.1503/cmaj.1032017

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
‍ Request Permissions
Share
Impact of specialist follow-up in outpatients with congestive heart failure
Justin A. Ezekowitz, Carl van Walraven, Finlay A. McAlister, Paul W. Armstrong, Padma Kaul
CMAJ Jan 2005, 172 (2) 189-194; DOI: 10.1503/cmaj.1032017
Digg logo Reddit logo Twitter logo Facebook logo Google logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Jump to section

  • Article
    • Abstract
    • Methods
    • Results
    • Interpretation
    • Footnotes
    • References
  • Figures & Tables
  • Responses
  • Metrics
  • PDF

Related Articles

  • Highlights of this issue
  • Patients with treatable malignant diseases — including heart failure — are entitled to specialist care
  • PubMed
  • Google Scholar

Cited By...

  • Rates and predictors of general practitioner (GP) follow-up postdischarge from a tertiary hospital cardiology unit: a retrospective cohort study
  • Effect of early physician follow-up on mortality and subsequent hospital admissions after emergency care for heart failure: a retrospective cohort study
  • Effect of cardiologist care on 6-month outcomes in patients discharged with heart failure: results from an observational study based on administrative data
  • Team-based innovations in primary care delivery in Quebec and timely physician follow-up after hospital discharge: a population-based cohort study
  • Variation in hospital performance for heart failure management in the National Heart Failure Audit for England and Wales
  • Providing Cardiology Care in Rural Areas Through Visiting Consultant Clinics
  • Use of hospital services by age and comorbidity after an index heart failure admission in England: an observational study
  • Regional Hospital Collaboration and Outcomes in Medicare Heart Failure Patients: See You in 7
  • In-hospital treatment and outcomes of heart failure in specialist and non-specialist services: a retrospective cohort study in the elderly
  • Physician Continuity Improves Outcomes for Heart Failure Patients Treated and Released From the Emergency Department
  • Do Outcomes for Patients With Heart Failure Vary by Emergency Department Volume?
  • Impact of physician continuity on death or urgent readmission after discharge among patients with heart failure
  • Postdischarge Outcomes in Heart Failure Are Better for Teaching Hospitals and Weekday Discharges
  • The coming crisis: Obtaining care for the growing burden of neurodegenerative conditions
  • Changes in Heart Failure Outcomes After a Province-Wide Change in Health Service Provision A Natural Experiment in Alberta, Canada
  • A Population-Based Study to Evaluate the Effectiveness of Multidisciplinary Heart Failure Clinics and Identify Important Service Components
  • Patterns of Care and Outcomes Differ for Urban Versus Rural Patients With Newly Diagnosed Heart Failure, Even in a Universal Healthcare System
  • Improved Outcomes With Early Collaborative Care of Ambulatory Heart Failure Patients Discharged From the Emergency Department
  • Declining In-Hospital Mortality and Increasing Heart Failure Incidence in Elderly Patients With First Myocardial Infarction
  • Telemonitoring or structured telephone support programmes for patients with chronic heart failure: systematic review and meta-analysis
  • Association between Multidisciplinary Care and Survival for Elderly Patients with Chronic Kidney Disease
  • The effect of specialist care within the first year on subsequent outcomes in 24 232 adults with new-onset diabetes mellitus: population-based cohort study
  • Impact of anemia on hospitalization and mortality in older adults
  • Time-dependent analysis in CHF follow-up
  • Time-dependent analysis in CHF follow-up
  • Patients with treatable malignant diseases -- including heart failure -- are entitled to specialist care
  • Google Scholar

More in this TOC Section

  • Falsely elevated point-of-care lactate measurement after ingestion of ethylene glycol
  • Severe necrotizing pancreatitis following combined hepatitis A and B vaccination
  • Can hockey playoffs harm your hearing?
Show more Research article

Similar Articles

Collections

  • Topics
    • Cardiology: heart failure

Content

  • Current issue
  • Past issues
  • Collections
  • Sections
  • Blog
  • Podcasts
  • Alerts
  • RSS
  • Early releases

Information for

  • Advertisers
  • Authors
  • Reviewers
  • CMA Members
  • Media
  • Reprint requests
  • Subscribers

About

  • General Information
  • Journal staff
  • Editorial Board
  • Governance Council
  • Journal Oversight
  • Careers
  • Contact
  • Copyright and Permissions

Copyright 2021, Joule Inc. or its licensors. All rights reserved. ISSN 1488-2329 (e) 0820-3946 (p)

All editorial matter in CMAJ represents the opinions of the authors and not necessarily those of the Canadian Medical Association or its subsidiaries.

Powered by HighWire