Medical statistics is a science that studies certain social processes related to hygiene and he alth care in general. This area examines the quantitative and qualitative characteristics of these phenomena, as well as their changes in time and space.
The second name of science is sanitary statistics. It is necessary to study many issues in the field of medicine, assess the current situation, make a possible forecast for the future, and so on.
There are a huge number of possible values in this area. In particular, when solving any problem, one cannot do without extensive indicators. They will be discussed below.
Classification of quantities in he alth statistics
In this area, absolute and relative values are distinguished. The first of these are often used in comparative and other analyses, but often do not give doctors complete information about some things (for example, disease statistics in the population).
Then relative values come to the rescue. They are a group of generalizingindicators that are used for in-depth analysis of the he alth of the population, the effectiveness of the functioning of medical institutions and even a particular employee. There are four types of such quantities:
- Ratio indicators - the ratio between several quantities that are not related to each other (for example, the number of abortions and childbirth, the number of doctors and nurses).
- Visibility indicators. They are needed when analyzing homogeneous numbers and their changes in dynamics.
- Intensive indicators show the frequency, the level of a particular process in the environment that creates it (for example, mortality, fertility, etc.).
- And finally, extensive indicators.
What is this?
Extensive is the distribution indicator, which is the ratio of one specific part to the general whole. It is usually expressed as a percentage. However, it is permissible, when necessary, to express the value in ppm.
If we talk about the formula, it will look like this:
Extensive indicator=part of the phenomenon × 100 / whole phenomenon.
Indicator functions
Extensive quantities are a necessary and useful thing in medical practice. Thanks to them, the epidemiologist can determine the structure of the entire set of the issue under study, give a comparative assessment between several groups and their quantitative ratio.
In this way, in medicine, for example, the ratio of leukocytes in the general blood test, the structure of morbidity, mortality is studiedby age or gender and more.
In addition, for a better understanding, it is worth saying that the sum of all indicators when solving a specific problem will eventually be equal to one hundred percent.
Let's put it into practice
In order to study the practical application of these values, a specific example should be analyzed.
Very often, calculations using extensive indicators in medical practice are resorted to during various epidemics. In such cases, it is required to calculate the number of people who fell ill with a certain disease, their percentage of the total number of people in the group, etc. In other words, without using these values, it is impossible to fully study any indicator of the incidence of the population.
For example, a school is quarantined because 60 cases of illness were detected in students during a medical examination.
Of which:
- 30 children fell ill with SARS,
- chickenpox - 10,
- hepatitis - 4,
- other diseases - 16 people.
The calculation of extensive quantities will look like this:
- In total, 60 sick children were identified. So we take 60 as 100%.
- Of these, symptoms of SARS occur in 30.
- So, 30 - x%. To find x, you need to use the formula above. X=30 × 100 / 60=50%.
- Thus, half of all cases are infected, according to statistics, SARS.
Similarly, we carry out calculations for all the restdiseases.
For hepatitis:
- 60 – 100%.
- 4 - x %.
- X=4 × 100 / 60=6.7%.
For chicken pox:
- 60 – 100%.
- 10 - x %.
- X=10 × 100 / 60=16.7%.
Other diseases (seasonal and other):
- 60 – 100%.
- 16 - x %.
- X=16 × 100 / 60=26.6%.
The last step in solving such a problem is to sum up the results:
50 + 6, 7 + 16, 7 + 26, 6=100%.
The use of extensive indicators is relevant in some other cases as well. For example, if you want to study:
- Sex ratio (men, women).
- Age categories (children under three, under 14, under 21 and so on).
- Social strata of society (homeless, unemployed, middle-income, etc.).
When not to use extensive measures?
- Their use is irrelevant when solving those problems when it is required to identify the dynamics of a certain phenomenon (increase or decrease in the number of cases, and so on).
- When comparing the severity of a certain trait in different population groups, it is also impossible to use these indicators.
Graphic
Since these indicators show only statistical data, it can be graphically depicted as a pie chart. Or the second option is an intra-bar chart.
Outwardly theyare geometric figures located in two dimensions, which contain any information data.
Example of building a pie chart
The distance describing the entire circle (360 degrees) is taken as 100%. Based on this, it turns out that one percent will be equal to 3.6 degrees.
Segments are drawn on the circle that correspond to the values of each group.
The resulting segments are connected to a point located in the center of the circle. Thus, as a result, sectors are obtained.
Each sector corresponds to its own group. For clarity, they are painted in different colors.
In sum, all these sectors, if connected together, will give a circle.
An example of such a chart is shown in the figure above. It clearly shows that most people are infected with a disease such as brucellosis. Its sector occupies the largest area of the circle. In second place is hepatitis, in third place is smallpox, and so on.
Example of building an intra-bar chart
The second option is an intra-bar chart. A rectangle of arbitrary height is taken. It will be taken as 100%. Place others inside this column, the height of which will show the extensive indicator of a particular group. The smallest column should be placed last.
This graph clearly shows that the largest percentage is occupied by diseases of the respiratory system, and the smallest - by other diseases not indicatedon the chart.
Requirements for charts
- Regardless of the chosen chart type, the chart should have a clear and understandable title. After reading it, it should be immediately clear what information is presented in the image.
- The scale and units of measurement of all quantities presented on the chart must be indicated.
- There should also be a brief explanation about the meaning of the received images.
Conclusion
Certainly, medical or sanitary statistics is a very useful and necessary science. Each value that is used in calculations in this area is necessary. After all, it carries certain information that is required to assess the he alth situation.
Extensive indicators are no exception. Without them, it would not be possible to fully study the data on the incidence of society, consider each group (a specific disease, age category or gender) separately and draw correct and timely conclusions.
