Cohort Study explained

00:03:08
https://www.youtube.com/watch?v=D7vk3zUmy1Q

Zusammenfassung

TLDRCohort studies are observational studies designed to link risk factors to diseases. Participants are selected based on their exposure status, forming groups of those exposed and not exposed to a risk factor. A prominent example is the British doctor study, which followed smokers and non-smokers for 50 years to evaluate lung cancer rates. Cohort studies can be either prospective or retrospective, with the former involving long-term follow-up and the latter allowing for quicker data evaluation. While cohort studies are powerful for establishing connections between characteristics and medical outcomes, they are time-consuming, expensive, and susceptible to biases such as participant dropout and behavior changes. The video also distinguishes cohort studies from case-control studies, emphasizing the difference in group selection criteria.

Mitbringsel

  • 📊 Cohort studies link risk factors to diseases.
  • 👥 Participants are selected based on exposure.
  • 🕰️ The British doctor study followed participants for 50 years.
  • 🔍 Cohort studies can be prospective or retrospective.
  • ⚖️ They are observational, meaning no intervention occurs.
  • 📉 Limitations include time consumption and potential biases.
  • 🚶‍♂️ Participant dropout can affect study results.
  • 🔄 Behavior changes may alter exposure over time.
  • 📈 Large cohort studies help establish risk factors.
  • ❓ Cohort studies differ from case-control studies in group selection.

Zeitleiste

  • 00:00:00 - 00:03:08

    Cohort studies are observational studies aimed at linking risk factors to diseases. Participants are selected based on exposure, with groups formed from those exposed and not exposed to a risk factor. A notable example is the British doctor study, which followed smokers and non-smokers over 50 years to assess lung cancer rates. Cohort studies can be prospective or retrospective, with the former requiring long-term follow-up and the latter allowing for quicker data evaluation. Unlike case control studies, which group participants based on outcomes, cohort studies group them based on exposure. While powerful for establishing connections between characteristics and medical outcomes, cohort studies are time-consuming, expensive, and susceptible to biases, including participant dropout and changing behaviors. Despite these limitations, they provide valuable insights into risk factors for diseases.

Mind Map

Video-Fragen und Antworten

  • What is the aim of a cohort study?

    To link risk factors and diseases.

  • How are participants selected in cohort studies?

    Based on their exposure to a risk factor.

  • What is a well-known example of a cohort study?

    The British doctor study.

  • What is the difference between cohort studies and case-control studies?

    Cohort studies allocate groups based on exposure, while case-control studies allocate based on outcomes.

  • What are the limitations of cohort studies?

    They are time-consuming, expensive, and may have biases due to participant dropout.

  • Can cohort studies be retrospective?

    Yes, cohort studies can also be retrospective.

  • What is a longitudinal study design?

    A study design where participants are followed over time.

  • What is the significance of the British doctor study?

    It assessed lung cancer frequency in smokers versus non-smokers over 50 years.

  • What are the risks associated with long-term cohort studies?

    Participant dropout and changing behaviors affecting exposure.

  • What type of studies are cohort studies classified as?

    Observational studies.

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Untertitel
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Automatisches Blättern:
  • 00:00:00
    cohort studies are observational studies
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    that are frequently used to answer
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    epidemiological questions before looking
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    at the typical features of a cohort
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    study make sure to subscribe to the
  • 00:00:12
    channel and activate the notification
  • 00:00:13
    Bell to stay
  • 00:00:17
    updated the aim of a cohort study is to
  • 00:00:20
    link risk factors and diseases
  • 00:00:23
    importantly the participants of a cohort
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    study do not have the disease of
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    interest at the start but instead the
  • 00:00:31
    cohorts are initially defined based on
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    some common characteristic the
  • 00:00:36
    participants are chosen based on their
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    exposure some participants have the
  • 00:00:41
    exposure at the time the study is
  • 00:00:43
    initiated others don't these two groups
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    form the cohorts a well-known example is
  • 00:00:50
    the British doctor study in which people
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    were divided into two groups with
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    different exposure smoking and
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    non-smoking as a longitudinal study
  • 00:01:00
    design participants are Then followed
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    over time sometimes many years until the
  • 00:01:05
    occurrence of the outcome of interest
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    can be statistically evaluated between
  • 00:01:10
    the different cohorts the prospective
  • 00:01:12
    British doctor study followed the
  • 00:01:14
    participants for 50 years and assessed
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    the frequency of lung cancer cases in
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    smokers versus non-smokers by the way
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    cohort studies do not necessarily have
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    to be prospective there are also
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    retrospective study designs the
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    selection is still based on the exposure
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    but instead of waiting multiple years
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    data evaluation can be accelerated both
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    cohort studies and case control studies
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    belong to the observational studies
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    meaning that researchers only observe
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    but don't intervene as both studies are
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    frequently mixed up it might help to
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    point out the difference the major
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    difference lies within the sample
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    selection in cohort studies the
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    allocation into groups is based on the
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    risk factor or exposure in contrast the
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    groups in case control studies are
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    defined based on the outcome or disease
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    cohort studies are a powerful way to
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    connect characteristics to Medical
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    outcomes however the study design also
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    Bears some limitations cohort studies as
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    longitudinal studies are time consuming
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    and thus expensive further cohort
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    studies have the risk for biases during
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    this long long-term study design it is
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    likely that participants are dropping
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    out over time also participants in one
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    cohort May alter their behavior so the
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    exposure may not be constant over the
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    study period despite the weaknesses
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    large cohort studies enable researchers
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    to draw conclusions regarding risk
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    factors for defined disease if you would
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    like to learn more about the study
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    design of a case control study or the
  • 00:02:56
    randomized control trial check out these
  • 00:02:59
    two videos videos here please subscribe
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    to the channel and leave a like if the
  • 00:03:03
    video was helpful to you thanks for
  • 00:03:07
    watching
Tags
  • cohort studies
  • observational studies
  • epidemiology
  • risk factors
  • British doctor study
  • longitudinal study
  • prospective study
  • retrospective study
  • case-control studies
  • medical outcomes