Section outline

  • Lecture: Person-time and Bias (In-Person Lecture)

    Fixed vs. open cohorts; the dynamic allocation of person-time in longitudinal cohorts; patient or survivor cohorts; particular bias issues discussed in the setting of patient cohorts (including selection bias, immortal-person time bias, measurement error bias, confounding by indication, and residual confounding); and how emulation of a target trial may help avoid some of these biases.

    Faculty: June Chan

    View Parts 1-3 of Person-time and Bias lecture BEFORE coming to class on Feb 18, 2021.


    • Required Reading (please read PRIOR to watching the lectures):

      Chapter 7, Rothman, Greenland, & Lash 3rd Edition

    • Recommended Reading:

      • Hernán MA et al, Specifying a target trial prevents immortal time bias and other self-inflicted injuries in observational analyses J Clin Epid, 2016; mainly Parts 1-3.  https://www.ncbi.nlm.nih.gov/pubmed/27237061

      Optional Reading:

      Emilsson L, García-Albéniz X, Logan RW, Caniglia EC, Kalager M, Hernán MA. Examining Bias in Studies of Statin Treatment and Survival in Patients With Cancer. JAMA Oncol. 2018, PubMed PMID: 28822996. https://www.ncbi.nlm.nih.gov/pubmed/28822996 



    • SurvivalAnalysis LEC 2016_OPTIONAL primer on Survival Analysis File

      For those interested in a bit more background information on survival analysis, please see this chapter written by Dr. McCulloch for the UCSF medical students, in 2016. We are sharing this supplemental information with his permission. Please note there may be internal references in this chapter to other texts from that course, which are not relevant for EPI207. (citation: Ch. 65 of the UCSF SOM Mechanisms, Methods, and Malignancy syllabus, 2016, copyright UC Regents)

    • Recorded Lectures (please watch PRIOR to class):

      Access restricted to registered students

    • Session Slides:

    • PT Bias Part 1 OpenFix Coh and Calcs EPI207_slides_no audio File
    • PT Bias Part 2 PT EPI207_slides no audio File
    • PT Bias Part 3 SurvCoh Conf EPI207 no audio File
    • 210218 PT Bias Part 4 Sel Bias ImmPT W21 with InClass QUES ONLY File
      Uploaded 02/18/21, 12:23
    • W21 PT Bias combined powerpoint BEF class File
      Uploaded 02/18/21, 12:26
    • 200130 InClass Exercise Ques withANSWERS File
      Not available unless: You belong to Registered Students Only

    • Session Audio/Video Recording (Access restricted to registered students):

    • Class Recording - Week 7 Media Resource
      Not available unless: You belong to a group in Registered Students Only

    • Assignment:

      Due Thursday, February 25, 2021 at the beginning of lecture

    • HW PT Bias Ques to Post W21 File
      Not available unless: You belong to Registered Students Only
      Uploaded 02/18/21, 12:32

    • Choe, K.S., et al, Aspirin use and the risk of prostate cancer mortality in men treated with prostatectomy or radiotherapy. 2012, Journal of Clinical Oncology, 30(28), pp.3540-3544.


    • Homework #6 Submission Assignment

    • Assignment Answer Key (access restricted to registered students):

    • W21 PT Bias KEY to post File
      Not available unless: You belong to Registered Students Only