1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Tresset [83]
3 years ago
14

How to put survival in study when subjects are added in 10 months period?

Social Studies
1 answer:
Evgen [1.6K]3 years ago
8 0
Learning Objectives

After completing this module, the student will be able to:

<span>Identify applications with time to event outcomesConstruct a life table using the actuarial approachConstruct a life table using the Kaplan-Meier approachPerform and interpret the log rank testCompute and interpret a hazard ratioInterpret coefficients in Cox proportional hazards regression analysis</span>

Time to Event Variables

There are unique features of time to event variables. First, times to event are always positive and their distributions are often skewed. For example, in a study assessing time to relapse in high risk patients, the majority of events (relapses) may occur early in the follow up with very few occurring later. On the other hand, in a study of time to death in a community based sample, the majority of events (deaths) may occur later in the follow up. Standard statistical procedures that assume normality of distributions do not apply. Nonparametric procedures could be invoked except for the fact that there are additional issues. Specifically, complete data (actual time to event data) is not always available on each participant in a study. In many studies, participants are enrolled over a period of time (months or years) and the study ends on a specific calendar date. Thus, participants who enroll later are followed for a shorter period than participants who enroll early. Some participants may drop out of the study before the end of the follow-up period (e.g., move away, become disinterested) and others may die during the follow-up period (assuming the outcome of interest is not death).

In each of these instances, we have incomplete follow-up information. True survival time (sometimes called failure time) is not known because the study ends or because a participant drops out of the study before experiencing the event. What we know is that the participants survival time is greater than their last observed follow-up time. These times are called censored times.

Censoring

There are several different types of censoring. The most common is called right censoring and occurs when a participant does not have the event of interest during the study and thus their last observed follow-up time is less than their time to event. This can occur when a participant drops out before the study ends or when a participant is event free at the end of the observation period.

In the first instance, the participants observed time is less than the length of the follow-up and in the second, the participant's observed time is equal to the length of the follow-up period. These issues are illustrated in the following examples.

 

Example:

A small prospective study is run and follows ten participants for the development of myocardial infarction (MI, or heart attack) over a period of 10 years. Participants are recruited into the study over a period of two years and are followed for up to 10 years. The graphic below indicates when they enrolled and what subsequently happened to them during the observation period.

During the study period, three participants suffer myocardial infarction (MI), one dies, two drop out of the study (for unknown reasons), and four complete the 10-year follow-up without suffering MI. The figure below shows the same data, but shows survival time starting at a common time zero (i.e., as if all participants enrolled in the study at the same time).


You might be interested in
"A testator wrote a will under circumstances in which a person the testator trusted took advantage of the testator's weak physic
Arisa [49]

Answer:

the will made with undue influence

Explanation:

A testator is simply an anyone who writes a will and also anyone who executes a valid will or  a given legacy.

In this scenario called undue influence where a person influences or persuades the testator to alter or  make some changes his or her will  due to the fact that  the testator vulnerable state(emotionally and physically unstable).

Anyone can influences a testator. the people who can easily persuade a testator to make changes in his/her will are those who are close to the testator and also recognizes that the testator is not emotionally and physically stable and so they persuades the testator to agree to their demand and make the changes in the will.

3 0
2 years ago
The __________ ________ suggests that keys to understanding development are observable actions and outside stimuli in the enviro
irakobra [83]

Answer: Behavioral perspective.

Explanation: Behavioral perspective is a theoretical perspective which entails learning and behaviour that are described and explained in terms stimuli response in the environment.

8 0
3 years ago
A temporary license permits the holder to drive for up to ___ days while the application is reviewed
jolli1 [7]
<span>A temporary license permits the holder to drive for up to 60 days while the application is reviewed.
After you pass a driving test, the government of the state need some time to register all your data and produce your driver license. During this time, temporary license permits act as a legal substitute for the driver license</span>
4 0
3 years ago
whether each of the following is a final​ good, an intermediate​ good, or neither. Coffee beans purchased by a coffee shop ▼ One
Liono4ka [1.6K]

Answer:

Explanation:

▼ Coffee beans purchased by a coffee shop   (intermediate good)

▼ One share of Google stock  (neither)

▼  A new​ pick-up truck purchased by a consumer (final good)

▼ A new home purchased by a family  (final good)

4 0
3 years ago
Which conflict theory of deviance could be criticized for blaming the people labeled as deviant, rather than those who label oth
viva [34]

The theory of conflict of deviance from retreatism is one whose scope is related to the individual's rejection of the goals of society and the legitimate means to achieve them, being considered as the true deviants, being a theory subject to criticism.

<h3 /><h3>What is deviance?</h3>

It is any socially constructed behavior that violates a group's rules, laws, or moral code. It is an integral part of every society, being a relative and not absolute practice.

Therefore, as it is a social construction, there is stigma on deviants, but it is essential to understand the motivations for committing such acts, establishing measures to combat and generate opportunities for all.

Find out more information about deviance here:

brainly.com/question/7582033

5 0
2 years ago
Other questions:
  • According to the online article about the Great Wall of China, one reason the wall was built was to protect merchants who were t
    14·1 answer
  • Where did the portuguese create their trading empire? Who did they replace as the dominant power?
    6·1 answer
  • In the context of reconstructing past attitudes, researchers had students write essays opposing student control over university
    15·1 answer
  • Proper logic states all valid arguments are sound arguments. all sound arguments are valid arguments. a sound argument may have
    8·1 answer
  • Identify the characteristics of the city-state of Sparta. Check all that apply.
    9·1 answer
  • Stereotype is defined as: A preconceived evaluative attitude based on a person's social group membership. An overgeneralized bel
    9·1 answer
  • What percentage of Americans is christen
    6·1 answer
  • Imagine that you were a roman christian traveller in the eurasian world of 500 ce writing home about your encounter with other r
    6·1 answer
  • Automatic stabilizers are defined as A. policy that has no multiplier effects. B. actions taken by the President without Congres
    9·1 answer
  • How old was geroge washington when he become president?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!