What is epidemiology?

Epidemiology, (from the Greek “epi”, “about;” demos “,” people “; and” logos “,” science “) is the study of the accident and trading of events, conditions, and processes related to health in the population.

medical science that studies diseases and their evolution in the culture as a whole Epidemiologists study the distribution, frequency, and factors that influence and rule the progression of diseases in a group of people.

The position of epidemiology in the biomedical sciences is very important, as it covers the gap between the health sciences and the social sciences.

It blends both biomedical and social methods and ethics to study health, control diseases in the population, and study their socio-economic and biomedical effects.

Although epidemiology originally appeared to study epidemics of infectious diseases such as cholera, Spanish flu, or plague, today it includes diseases that are not necessarily due to bacteria and viruses, such as lung cancer.

The cause of smoking, addictions, in addition to the appearance of mental disorders such as bipolar, anorexia nervosa, or depression, among others.

Descriptive epidemiology

Study the frequency and distribution of diseases and health parameters in populations. Describes health events such as illness, causes of death, and the presence of risk factors such as tobacco smoke, air pollution, etc.

This is the branch that uses statistical tools such as frequency measurements (such as incidence or prevalence rate, reports) and the information-type population.

He aims to answer questions such as: “Who got sick? Where? When?”. Descriptive epidemiology contributes to analytical epidemiology. The investigative tools used by descriptive epidemiology are: ecological studies;

cross-sectional studies (these are observational, descriptive studies).

Analytical epidemiology

Study the cause-and-effect relationships between risk factors and disease. Taking the above example, analytical epidemiology looks for the link between the risk factor, for example.

“Cigarette smoke”, “air pollution”, “electromagnetic field”, etc., and the occurrence of possible pathologies related to it (such as lung cancer, emphysema, brain tumor, mortality complex, etc.).

As the main objective, we propose to answer two questions:

the type of “exposure” or “risk factor” (electromagnetic fields, air pollution, endocrine disruptors, etc.) what specific diseases can it cause?

those specific diseases/deaths (e.g., depression, hypertension, brain tumor, etc.) that can cause possible “exposure”?

The investigative tools used by analytical epidemiology are:

cohort studies: compare mortality and/or incidence rates of specific diseases in different exposed (and unexposed) populations;

case-control studies: compare the frequencies of possible exposures and/or risk factors in the group of “cases” (specific patients, eg multiple sclerosis) and “witnesses”, ie nebulous subjects (from the disease in question: eg sclerosis multiple).

Experimental epidemiology

Evaluate the effectiveness of health interventions following epidemiological investigations.

Experimental epidemiology studies can be both preventive (eg, assessing the success of awareness campaigns) and therapeutic (eg, drug studies and operating techniques).

Experimental epidemiology studies can be performed single-blind, double-blind, or triple-blind; respectively the studies for which:

only the volunteers do not know that they are in the control or experimental group;

even the researcher does not know who belongs to one group and who belongs to another (only the supervisor knows);

relies on an external researcher.

Sometimes, especially in recent years, there are distorted uses of epidemiological studies, of certain diseases with a high social impact, on pharmaceutical marketing practices.

What is taken into account when studying epidemiology?

Epidemiologists, when studying a disease, whether it is caused by a living pathogen, such as bacteria, or by population habits,

such as sedentary lifestyle and smoking, consider a number of models of the medical or psychiatric condition to be studied:

1 time

Over time, it refers to the time when it occurs, especially if it is a disease with a possible contagious cause, and may have the highest points at a certain time of year.

2 Sit down

It is the physical place, as a city, a country, the characteristics of the area where there have been several cases…

3 people

We refer to people who are more likely to have a certain biomedical condition, ie the risk group.

Usually, in contagious diseases, the groups most at risk are newborns and the elderly.

Epidemiological methodology

The epidemiological methodology uses the experimental scientific method because this discipline.

in order to increase its knowledge must use real cases that have appeared in the population.

That is, look at how many new cases of the disease there are,

what individual characteristics make these cases manifest the disease, what caused the fact that elsewhere there was no such incidence …

The epidemiological method mainly uses quantitative techniques. Epidemiological studies do not modify or manipulate the factors that act on humans, unlike a laboratory experiment,

in which the characteristics of the person, the type of stimuli, or environmental factors to which they are subjected are controlled, among others.

Determine the extent of the disease

It tends to measure what happens in the population, what are the rates of mortality, incidence, and prevalence of diseases, in addition to the prevalence of risk factors.

All this serves to know the specific characteristics of the health or diseases of a population,

in addition to the fact that they can monitor over time how changes in these characteristics take place.

For example, epidemiology would study why there is more mortality in one region than in another,

what genetic and indirect factors make a population more vulnerable,

or what eating habits or habits that involve risk would explain the incidence of the disease.

Identify the determinants of the disease

As we have seen, from its beginnings, epidemiology has tried to find out the reason for the appearance of a certain state of health and what are the causes that affect the pathological process.

In essence, it is responsible for identifying risk factors when it comes to the manifestation of a medical illness or a psychological disorder.

Complete clinical charts

In clinical medicine, epidemiology has a very useful function,

as it allows the specification, through epidemiological and statistical criteria, of what the patient suffers.

An example of this was the case of rapeseed oil infection. Through epidemiological research, it has been possible to discover that the disease manifested by thousands of people was caused by the respective consumption of oil.

Detect new diseases

The emergence of new cases of unknown diseases is studied by the epidemiological method.

This was the case with HIV / AIDS. It has been found that patients develop rare pneumonia, which only affects people who have symptoms of immunosuppression.

Contributes to health planning

Although previous applications already contribute to health planning,

epidemiology is also used specifically to know the specific needs of health services, for example, the design of health plans.

Contribute to training

Epidemiology is not just about finding out how disease occurs,

what its prevention is, what population is at risk, and other issues directly related to biomedical status.

 It also aims to train medical staff so that, in the event of the disease,

they know, by consulting the biomedical literature and knowing the symptoms of a health condition in question, what they should do and how to prepare.