The Kaplan–Meier estimator is a product limit estimator that is used for estimating the survival function from lifetime data [24]. The aim of this estimator is to estimate a population of patients’ survival curve from a sample. This estimator is used in addition to the Receiver-operator characteristic ROC curve to evaluate the performance of the prediction model [25-27]. Of course, if every patient is followed until death, the curve may be estimated simply by computing the fraction surviving at each time. However, in most medical studies patients tend to drop out, become lost to follow up, move away, etc. The Kaplan-Meier analysis allows estimation of survival over time, even when patients drop out or are studied for different lengths of time. …show more content…
Patients who have died, dropped out, or not reached the time yet are not counted as “at risk.” On the other hand, patients who are lost are considered “censored” and are not counted in the denominator. The probability of surviving to any point is estimated from cumulative probability of surviving each of the preceding time intervals (calculated as the product of preceding probabilities). Although the probability calculated at any given interval isn’t very accurate because of the small number of events, the overall probability of surviving to each point is more accurate. Thus the plot of the Kaplan–Meier estimate of the survival function is a series of horizontal steps of declining magnitude which, when a large enough sample is taken, approaches the true survival function for that population. The value of the survival function between successive distinct sampled observations ("clicks") is assumed to be constant. If a patient withdraws from a study, i.e. is lost from the sample before the final outcome is observed then small vertical tick-marks on the plot indicate losses, where a patient's survival time has been right-censored. When no truncation or censoring occurs, the Kaplan–Meier curve is the complement of the empirical distribution
In the book The Examination by Malcolm Bosse two brothers travel across China in their journey to pass the Imperial Exam. The brother’s names are Chen and Hong. Chen is very intelligent and is taking the Civil Service Exams hoping to pass. Hong on the other hand, is a known cricket fighter and joins the White Lotus Society along with the army. The Examination takes place in Song Era and is very accurate about what Chinese life and society was like in that time. This book depicts ideas and technologies and religious structure of ancient China. In the book The Examination by Malcolm Bosse, the author depicts ideas and technologies such as the civil service exam, junk ships, and porcelain as well as the religious structure of
Flinker S., Ward D., Calabrese T., (2013). Accounting Fundamentals for Health Care Management, 2nd edition.
“Conducting a Biopsychosocial Assessment” by Kathleen McInnis-Dittrich is another interesting reading that I definitely enjoyed. It’s very interesting to know that there is an assessment that actually can tell professionals what are the strengths and challenges of an older person. Older people can be evaluated with the biopsychosocial assessment and how support or rehabilitative services can help older adults to maintain independent and satisfying lifestyles could be identify (McInnis-Dittritch, 2014).
Liem E, Lin C, Suleman M et al. Anesthetic requirement is increased in redheads. Anesthesiology. 2004;101(2):279-283.
The purpose of this lab was to determine how changes in human mortality and survivorship have influenced population growth.
Over recent years FEMA has increase their involvement in the community. After a catastrophic event FEMA is able to coordinate the efforts to build, rebuild and stabilize the region. The Mayor of New Jersey asked residents to send messages to his own Twitter account if they required help, and provide information the city’s snow cleanup effort back out to residents (Siegriest, 2010). The betterment of the technology and science underlying the biological aging process has the potential to not only extend the average lifespan, but also to simultaneously postpone many if not all of the disabling and costly conditions that individuals experience in later life, thereby creating a longevity dividend that will be social, medical and economical
The Diagnostic and Statistical Manual of Mental Disorders (DSM) has been used for decades as a guidebook for the diagnosis of mental disorders in clinical settings. As disorders and diagnoses evolve, new versions of the manual are published. This tends to happen every 10 years or so with the first manual (DSM-I) having been published in 1952. For the purpose of this discussion, we will look at the DSM-IV, which was published originally in 1994, and the latest version, DSM-5, that was published in May of 2013. Each version of the DSM contains “three major components: the diagnostic classification, the diagnostic criteria sets, and the descriptive text” (American Psychiatric Association, 2012). Within the diagnostic classification you will find a list of disorders and codes which professionals in the health care field use when a diagnosis is made. The diagnostic criteria will list symptoms of disorders and inform practitioners how long a patient should display those symptoms in order to meet the criteria for diagnosis of a disorder. Lastly, the descriptive text will describe disorders in detail, including topics such as “Prevalence” and “Differential Diagnosis” (APA, 2012). The recent update of the DSM from version IV-TR to 5 has been controversial for many reasons. Some of these reasons include the overall structure of the DSM to the removal of certain disorders from the manual.
Despite the whole blood sample that was used for this experiment being delivered many days before being used, the viability of the lymphocytes was still very high for most of the group data. This data could be inaccurate due to the device used to count the cell viability, the hemocytometer, because subjectivity of the individuals counting the cells or misuse of the technology itself (Cell Counting 2018). Possible errors that could have led to a lower percent viability could be not pipetting the leukocytes gently enough, causing them to
Assessing and determining a mental health diagnosis can be difficult because many of the disorders have similar presenting symptoms. In addition, a client may not outwardly present symptoms, therefore, the only way to detect them involves using a scale. Finding a reliable and valid scale that determines whether an individual meets the diagnostic criteria can be very useful. The DSM-5 is important in the diagnosis of dissociative disorder. The application of the tool has advantages and disadvantages depending on the specific individual and environment.
In my own experience and visits to different kinds of doctors from my normal doctor, to my dermatologist and my gynecologist most of my health care experiences have been biopsychosocial.
Figure 2. The values of dx, the proportion of the cohort that died in each age class. There is a very high proportion that died from both sexes in age class 0-9, indicating high infant mortality. Thereafter, the proportions steadily decreased for the females as there were fewer individuals that remained alive. The proportion of males
In today’s highly competitive job market it is extremely challenging and important for businesses to fill a vacancy with the right candidate (Cann, 2013). Due to high demand of potential candidates, developing a portfolio of employability skills which include psychometric testing is considered important in every workplace (Mills et al., 2011). Thus, I recently took three practice psychometric tests on verbal, numerical and inductive/logical reasoning. This essay is a reflection of my personal experience of psychometric testing. First, I will talk about what the literature comments on in relation to the strengths and weaknesses of psychometric testing. Then, I will assess whether literature reflects
Ravi, Sreenivasan. "Statistical And Probabilistic Methods In Actuarial Science." Journal Of The Royal Statistical Society: Series A (Statistics In Society) 172.2 (2009): 530. Business Source Premier. Web. 25 Oct. 2013.
Centenarian longevity is very much based on the internal physiological functioning and health input and output of these individuals. Physiological functioning including the immune system functioning has seen to be maintained and even increased for these longevous human beings. Neutrophilic functioning for fighting infection, and gluthathione and catalyst activity are also maintained through the century years. These results show high correlations between the levels of centenarians, and those of young adults. Genetic-wise, the longer the telomere, the longer the lifespan, due to cell division. Polymorphic genes regulate the immune system and other surrounding structures, maintaining its functions. Furthermore, health-conscious individuals are more likely to maintain a longer life, and reach the century age. This is due to maintenance of functioning by adapting healthy routines throughout their lifetime, even through old age. In conclusion, maintenance of the body and physiological aspects similar to young adults at old ages show a great increase in surviving and living beyond 100 years.
Aging, as exhibited within the immunity theory, was described as a pre-programmed accumulation of damage, decay and decline within the function of the immune system caused by oxidative stress as a result of the Hayflick limit or biological clock (Touhy and Jett, 2012). This limit refers to the idea that aging is the result of cell and organisms containing a genetically predetermined life span (Touhy and Jett, 2012). This suggested that in relation to a cell’s proliferative instinct, aging becomes more relevant within an individual when the cells reach the limit, introducing cellular errors of imperfect proliferations that result into further damage. Furthermore, no cell within the body has seemed to be above this concept, including the B lymphocytes and T lymphocytes of the immune system. In fact, cellular errors within the immune system have been found to cultivate an autoregressive phenomenon in which normal cells are misidentified as foreign and are consequently destroyed by the body’s own immune system (Touhy and Jett, 2012). The dest...