home
about the project
Medical news
For authors
Licensed books on medicine
<< Previous Next >>

MEASUREMENT OF COMMUNICATION BETWEEN PHENOMENA. METHODS FOR STUDYING CORRELATION RELATIONS IN THE EVALUATION OF HEALTH INDICATORS AND ENVIRONMENTAL FACTORS

LESSON PURPOSE: To master the principles of measuring correlation and master the technique of measuring the relationship between phenomena.

LESSON METHODOLOGY: Students independently prepare for a practical lesson in the recommended literature and complete their individual homework. The teacher within 10 minutes checks the correctness of homework and indicates the mistakes made, checks the degree of preparation using testing and an oral survey. Then students independently calculate the correlation coefficients by the method of squares (Pearson) and by the method of ranks (Spearman); assess the reliability of the correlation coefficient. Evaluate the data and formulate a conclusion. At the end of the lesson, the teacher checks the students' independent work.

TEST QUESTIONS:

1. What types of connections exist between phenomena or signs?

2. Is the functional relationship characteristic of biomedical phenomena?

3. What is a correlation?

4. Is it possible to consider that with a correlation, the value of one attribute corresponds to several values ​​of another, related to it attribute?

5. Is it possible to say that the correlation is manifested in the mass of observations, ie In total?

6. What is the criterion for assessing the nature and strength of correlation?

7. Can it be argued that the correlation coefficient gives an idea of ​​the presence and direction of the correlation?

8. With an increase in body temperature, the pulse rate in most patients increases. Can it be argued that such a relationship relates to direct correlation?

9. Is it possible to assert that the range of values ​​of the correlation coefficient is in the range from -1 to +1?

10. What are the methods for determining the correlation coefficient?

11. Is it possible to say that the method of squares (Pearson) gives more accurate results compared to the method of ranks (Spearman)?

12. What is the procedure for determining the correlation coefficient by the rank method?

13. How is the nature and strength of communication determined by the correlation coefficient?

14. How is the reliability of the correlation coefficient estimated?

15. Can it be argued that if the correlation coefficient is more than three times its error, is it reliable?

SUMMARY OF TOPIC:

The task of each science is to open and study the most significant connections between phenomena and processes. Two types of connection between phenomena (signs) are known: functional and correlation. A functional relationship reflects a strict dependence of processes or phenomena, and a change in any one phenomenon is necessarily associated with a change in the numerical values ​​of another phenomenon by a strictly defined value. Functional relationship, as a rule, manifests itself in physical and chemical phenomena, where it can be represented in the form of equations, formulas. Examples of functional communication may be an increase in the volume of the ball in strict dependence on an increase in its radius, expansion of the body as the heating temperature increases, etc. Correlation is a concept that also means the relationship between attributes. In correlation relationships characteristic of biomedical phenomena, the value of one sign corresponds to different values ​​of other signs. Correlation is necessary, for example, when assessing the relationship between work experience and the incidence of workers; between different levels of physical environmental factors and health status; between different levels of load intensity and the frequency (level) of physiological reactions of the body; between periods of hospitalization and the frequency of complications. Statistics allow the researcher to measure connections, substantiate conclusions and clearly illustrate them. The correlation is positive - direct (when increasing one attribute increases the other) and negative - inverse (when increasing one indicator, the other decreases). The correlation coefficient indicates not only the direction of communication, but also the level of this connection. Strong connection is expressed by a coefficient from 0.7 to 0.99, average - from 0.3 to 0.69, weak - up to 0.29. At a zero value of the coupling coefficient are absent.

The magnitude of the coefficient sets the direction and strength of the connection. The reliability of the coefficient is determined by the tables of critical values ​​(Kaminsky tables) with n '= n-2 (Appendix, Table 4), as well as when calculating the average error and reliability criterion t. The correlation coefficient should exceed its error by at least 3 times.

The values ​​of t are estimated from the table of critical values ​​of the criterion t (for n <30, Appendix, Table 2).

TASK FOR INDEPENDENT WORK:

TASK 1: Calculate the coefficient of rank correlation, determine the direction and strength of the correlation, evaluate the reliability of the data

Task 1

Is there a connection between work experience at a machine-building enterprise and the incidence rate of workers?

Task 2

Is there a relationship between the age of people with influenza and the mortality rate from this disease?

Task 3.

Is there a relationship between male age and mortality

Task 4.

Is there a relationship between the proportion of the frequently ill (BW) contingent and the age of children

Task 5.

Is there a relationship between age and frequency of visual impairment in children

Task 6.

Is there a relationship between the serial number of the month of the year and the frequency of the population seeking emergency and emergency medical care for cardiovascular diseases

Task 7.

Is there a connection between the distance from the place of residence to the enterprise and the incidence of workers

Task 8.

Is there a connection between the time elapsed from the occurrence of an acute attack of cholecystitis before the operation and the frequency of postoperative complications

Task 9.

Is there a connection between the age group and the frequency of suicides in men

Task 10.

Is there a relationship between the age group of men and the prevalence of mental illness

Task 11.

Is there a relationship between the age of the child and the number of patients with equinovarus deformity of the feet due to spastic paresis in the lower extremities

Task 12.

Is there a connection between the age group and the level of injury in men

Task 13.

Is there a relationship between the age and mortality rate of women in the Russian Federation

Task 14.

Is there a relationship between the age group of patients and the percentage of patients who are completely satisfied with the quality of treatment in a hospital?

TASK 2: Calculate the correlation coefficient by the square method (Pearson), determine the direction and strength of the correlation, evaluate the reliability of the data

Task 1

Is there a relationship between the proportion of children reached with measles vaccines and the incidence of measles?

Task 2

Is there a connection between height and body weight in medical students under the age of 19

Task 3.

Is there a connection between work experience in workshops with harmful working conditions and the incidence rate with temporary disability

Task 4.

Is there a relationship between length and body weight in newborns

Task 5.

Is there a relationship between the number of bacteria that grow when sowing 0.1 ml. disinfected water and a dose of residual chlorine in 1 ml. water

Task 6.

Is there a relationship between the puerperal age and the amount of breast milk

Task 7.

Is there a relationship between the duration of cooling the body and the level of lactic acid (mg%)

Task 8.

Is there a relationship between the age of patients and their need for medical care (equivalent units per 1 person)

Task 9.

Is there a connection between air temperature in autumn and the frequency of acute respiratory viral infections

Task 10.

Is there a connection between the age and incidence of medical students

Recommended Reading.

• Yu.P. Lisitsyn. Public health and healthcare. Textbook for high schools. M., 2002. –s. 303-304.

• Yu.P. Lisitsyn. Social hygiene (medicine) and healthcare organization. Kazan, 1999. - p. 306-307.

• VK. Yuriev, G.I. Kutsenko. Public health and healthcare. S.-P., 2000.- p. 1999-201.

• A.F. Serenko, V.V. Ermakov. Social hygiene and healthcare organization. M., 1984. — pp. 149-158.

• Public health and healthcare. Ed. V.A. Minyaeva, N.I. Vishnyakova. M. "MEDpress-inform", 2002. –s. 110-112.
<< Previous Next >>
= Skip to textbook content =

MEASUREMENT OF COMMUNICATION BETWEEN PHENOMENA. METHODS FOR STUDYING CORRELATION RELATIONS IN THE EVALUATION OF HEALTH INDICATORS AND ENVIRONMENTAL FACTORS

  1. Methodological foundations of the study of the relationship of the incidence of parasitosis with contamination of their pathogens
    The health status of the population is the main forming factor in the system of human sciences and the main criterion for assessing the quality of the environment. Assessment of the environmental impact on the spread of intestinal parasitoses is one of the essential components of a comprehensive analysis of the relationship of environmental factors and living conditions of the population with their state of health. Based on own results
  2. USE OF THE STANDARDIZATION METHOD IN ASSESSING POPULATION HEALTH AND PERFORMANCE INDICATORS OF HEALTH INSTITUTIONS
    LESSON OBJECTIVE: To master the direct method of standardization. To be able to calculate intensive, expected (conditional) and standardized indicators, analyze and compare intensive and standardized indicators, draw a conclusion. LESSON METHODOLOGY: Students independently prepare for a practical lesson in the recommended literature and complete their individual homework.
  3. Public health as an integral criterion for assessing the state of the environment
    In May 1998, the World Health Assembly approved the World Health Declaration for countries belonging to WHO, which noted that improving the health and material condition of the population is the ultimate goal of social and economic development. The importance of the health problem has especially increased recently, as the health status of the population has changed significantly,
  4. Investigation of the relationship between indicators of general and special chemical abilities in adolescents and students
    The study included 2 stages: at the first stage, the process of forming conceptual chemistry structures in adolescents aged 14–15 years was studied, and at the second stage, features of the conceptual chemistry structures among second-year students (19 years old) in the Faculty of Chemistry were studied. 1. A correlation analysis of the relationships between intelligence indicators and the time of differentiation of chemical concepts shows that in the process of formation
  5. ASSESSMENT OF INDICATORS OF CORRELATION RHYTHMOGRAPHY
    When screening, scatterogram values ​​are not evaluated. Typically, a scattergram is displayed in the range of 0.4 to 1.4 seconds. When you change the range visually, the dimensions of the scatterogram change. This circumstance is used when a detailed review of the elements of the graph is necessary. {foto161} {foto162} Scattergram of the patient in the range of 0.4-1.4 sec. That
  6. Resuscitation and intensive care with adverse environmental factors.
    Lecture 7 (for paramedics) Hyperthermia. Overheating of the body is a condition that occurs under the influence of high ambient temperature and factors that impede heat transfer. Such situations arise due to a prolonged stay in a room with a high temperature and the simultaneous performance of hard work, with
  7. PATHOLOGY CAUSED BY ENVIRONMENTAL FACTORS
    The words of the famous physician of antiquity Paracelsus (1493-1541), who believed that "Everything is poison and nothing is without poison" can be put as an epigraph to this lecture. In fact, the problem of pathology caused by environmental factors covers almost all human diseases. Some diseases, of which there are a great many, are caused by direct exposure to unfavorable factors.
  8. LUNG DISEASES DUE TO ENVIRONMENTAL FACTORS
    Frank E. Speizer This chapter focuses on the perspectives of environmental assessment of lung disease. This assessment is very important, since the elimination of harmful factors from the environment can often be the only way to prevent further deterioration of the patient's condition. In addition, the identification of these diseases in one patient may
  9. The nature of adverse environmental factors.
    Xenobiotics. The nature of adverse environmental factors leading to the development of pathological processes in humans can be different - chemical and physical. Chemical alien factors are called xenobiotics. Xenobiotics (gr. Xenos alien + bios life) - compounds alien to the body (pesticides, household chemicals, medicines, etc.), which, getting into
  10. Health effects of the environment
    At present, extensive scientific material has been accumulated proving the direct impact of a number of environmental factors (climate, weather, ecological situation) on human health. Based on extensive material, biometrics (a science that studies the dependence of well-being on the weather) has developed a kind of “calendar” of diseases that are characteristic of medium geographical
  11. Quantitative epidemiological significance of indicators of pollution by pathogens of parasitoses of environmental objects
    In this section, an attempt is made to analyze literature data and the results of our own studies to determine the levels of pollution of various environmental objects (soil, surface water, drinking water, sewage, vegetables, etc.), in which the development of the epidemic process with parasitosis is suspended and distribution is excluded
  12. DISEASES CAUSED BY ENVIRONMENTAL FACTORS
    DISEASES CAUSED BY ENVIRONMENTAL FACTORS
  13. EMF as a factor in the environment and production environment
    Every person encounters EMF every day, both in domestic and in production conditions. Therefore, the question of creating the so-called electromagnetic population comfort, i.e. optimization of electromagnetic living conditions and human activities. According to the International Classification, anthropogenic sources of EMF are divided into 2 groups: 1 group — generating
Medical portal "MedguideBook" © 2014-2019
info@medicine-guidebook.com