Medical statistics is a science that studies certain processes occurring in society that are related to hygiene and public health in general. This area considers the quantitative and qualitative characteristics of these phenomena, as well as their changes in time and space.
The second name of science is health statistics. It is necessary for studying many issues in the field of medicine, assessing the current situation, making a possible forecast for the future, and so on.
In this area, a huge number of possible values are used. In particular, in solving any problem, extensive indicators are indispensable. About them and will be discussed below.
Classification of values in health statistics
In this area, absolute and relative values are distinguished. The first of them are often used in comparative and other analyzes, but they often do not give doctors complete information about some things (for example, statistics on morbidity among the population).
Then relative values come to the rescue. They are a group of general indicators that are used for a deep analysis of public health, the effectiveness of the functioning of medical institutions and even a specific employee. There are four types of such quantities:
- Ratios - the ratio between several values that are not related to each other (for example, the number of abortions and childbirth, the number of doctors and nurses).
- Indicators of visibility. They are needed when analyzing homogeneous numbers and their changes in dynamics.
- Intensive indicators demonstrate the frequency, level of a particular process in the environment that creates it (for example, mortality, fertility and the like).
- And finally, extensive indicators.
What it is?
Extensive is the distribution indicator, which is the ratio of one particular part to the 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 metric = part of a phenomenon × 100 / whole phenomenon.
Metric Functions
Extensive quantities are a necessary and useful thing in medical practice. Thanks to them, the epidemiologist can determine the structure of the entire population 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 a general blood test, the structure of morbidity, mortality by age or gender, and much more are studied.
In addition, for a better understanding, it is worth saying that the sum of all indicators in solving a specific problem in the end will necessarily be equal to one hundred percent.
We will analyze in practice
In order to study the practical application of these quantities, a specific example should be considered.
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 cases of 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 a single indicator of the incidence of the population.
For example, the school is quarantined for the reason that 60 cases of illness were detected in students during a medical examination.
Of them:
- SARS sick 30 children
- chickenpox - 10,
- hepatitis - 4,
- other diseases - 16 people.
The calculation of extensive quantities will look like this:
- A total of 60 sick children were identified. So, we take 60 for 100%.
- Of these, ARVI symptoms occur in 30.
- So, 30 - x%. To find x, you need to use the formula presented above. X = 30 × 100/60 = 50%.
- Thus, half of all cases are infected, according to statistics, SARS.
Similarly, we carry out calculations for all other diseases.
For hepatitis:
- 60 - 100%.
- 4 x%.
- X = 4 × 100/60 = 6.7%.
For chickenpox:
- 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 this problem will be the summation of the results:
50 + 6.7 + 16.7 + 26.6 = 100%.
The use of extensive indicators in some other cases is also relevant. For example, if you want to learn:
- The ratio of sex groups (men, women).
- Age categories (children under three, under 14, under 21, and so on).
- Social strata of the society (without a fixed place of residence, unemployed, with an average level of earnings, and so on).
When can I not use extensive indicators?
- Their use is irrelevant in solving those problems when it is necessary to identify the dynamics of a certain phenomenon (increase or decrease in the number of patients and so on).
- When comparing the severity of a particular trait in different population groups, it is also impossible to use these indicators.
Graphic image
Since these indicators show only statistical data, this can be graphically depicted in the form of a pie chart. Or the second option is the intra-column diagram.
Outwardly, they are geometric figures located in two dimensions, which comprise any informational data.
Pie chart example
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.
Pieces that correspond to the values of each group are applied to the circle.
The resulting segments are connected to a point located in the center of the circle. Thus, the result is a sector.
Each sector corresponds to its group. For clarity, they are painted in different colors.
In total, all these sectors, if combined together, will give a circle.
A sample of such a diagram is presented in the figure above. It clearly shows that most people are infected with a disease such as brucellosis. Its sector occupies the most extensive circumference. In second place is hepatitis, in third is smallpox, and so on.
An example of building an in-line chart
The second option is the intra-column diagram. A rectangle of arbitrary height is taken. It will be taken as 100%. To place others inside this column, the height of which will show the extensive indicator of a particular group. The last column should be the smallest column.
This graph clearly shows that the largest percentage is occupied by respiratory diseases, and the smallest is by other diseases not shown in the diagram.
Chart Requirements
- Regardless of the type of chart chosen, the chart should have a clear and understandable name. After reading it, it should be immediately clear what information is presented in the image.
- Be sure to indicate the scale and units of measurement of all quantities presented on the graph.
- There should also be a brief explanation of the meaning of the received images.
Conclusion
Of course, medical or sanitary statistics is a very useful and necessary science. Each value that is used in the calculations in this area is necessary. After all, it carries certain information that is required to assess the health situation.
Extensive metrics are no exception. Without them, it would not be possible to fully study the data on the incidence of society, to consider each group (a specific disease, age category or gender) separately and draw correct and timely conclusions.