Selection Bias In Research – Definition, Types & Examples


The research work is becoming complex because of the advancement in technology. So, you have to be careful about all of its aspects. One of the main problems which keep researchers struggling is the bias in research. There are several types of bias, and each type affects the credibility of writer to a great extent. The purpose of knowing about bias and its different forms is to make your research effective and free from flaws. Ending up with reliable research work is the aim of every researcher, but the lack of information makes it difficult. Biasness in research is something that ruins all of the efforts of the researcher. From several forms, one of the most commonly observed types of research bias is selection bias. This article aims to discuss selection bias in detail, and you will not end up with any confusion while working on the research task

What is Meant by Selection Bias? 

In research work, researchers have to put in a lot of effort to find the best end results. The inconstancy in research outcomes is mostly observed because of selection bias, which occurs when there is an improper sample size and method. In every research work, researchers are supposed to be very conscious about the sample size. A small mistake in sample size leads to the failure of research.

While making samples, intervals can be made for the collection of research data. A proper formula is used to determine the interval and then production of the designed product for standard quality check. For calculating the sample interval, you are supposed to divide population units by the total sample size. That is how, sampling finds significant use in research related to industrial and other projects. At an industrial level, it may be challenging to test each product, so data sampling in intervals works well to save time and effort. Here, each product after a particular interval is tested to present all units of sampling.

When you fail to make accurate samples, it becomes stimulating to find the best results. In order to avoid selection bias, you are supposed to target the right audience and collect accurate data. With improper samples, you cannot reflect the potential audience in your research. Also, the risk ratio is neglected up to a great extent. There can be two reasons behind this ignorance. The first one is the lack of information, while the second one is the negligence of researcher. Other than these reasons, there can be an inappropriate contribution from the targeted audience. 

What Are The Different Types Of Selection Bias?

There are three main types of selection bias. These types are mentioned below, and their description is also present:

Survivorship Bias 

This is one of the types of selection bias which occur when there is a lack of proper screening context. In this way, it becomes difficult to define the right variables for research. With the wrong variables, it is obvious that the research outcomes would not be accurate. With survivorship bias, you start laying the wrong foundation. First of all, their selection of the wrong variable is there, and secondly, the collection of data for each variable is inaccurate. So, you can see that the whole process gets affected by it, and real-life problems cannot be solved through it. 

For example, when you target teenagers for a research study of civilians, there will be a survivorship bias. Hiring the best Dissertation writers UK can be a good option to consider for having proper guidelines of survivorship bias. 

Exclusion Bias 

Another type of selection bias is exclusion one which occurs when all targeted audiences do not get a chance to participate in research. In this type of bias, the researcher is responsible because the negligence of the researcher cause extraction of a group of people from targeted audience. 

In research work, the area of discussion matters a lot. When you go for generalization of research, you do not find clear boundaries to define. In this context, there are chances that you may be biased in your research, and you may ignore a particular group of populationIn order to avoid exclusion bias, you have to evade generalization in research. You should prefer a defined area where it would become easy to discuss things in the right direction.

Volunteer or Self-Selection Bias 

Volunteer bias is also known as self-selection bias, which is observed when there is no clear difference between the targeted and untargeted audience for research work. The chances of volunteer bias in research increase up to a great extent when the topic of discussion is controversial. Whatever the research topic is, you do not have to be critical of a particular side of the discussed problem. In this case, the standard style and tone can also help you. Both the style and tone should be formal with the right choice of words. 

Also, you need to plan things beforehand. When you start making a research plan, you have to keep the point of volunteer bias in your mind. When you highlight this aspect while planning, it keeps you conscious about audience type. For example, at the time of making the questionnaire, you will be careful about the nature of question and audience accordingly. Similarly, at interview time, you can follow a better course of action. While working on this selection bias, you can contact with professionals to buy dissertation online.

Final Thoughts 

By reading and understanding the above-mentioned pointers, you can learn all about selection bias. While working on your research, you have to be vigilant and identify what type of selection bias is present in your work. After that, you need to work on strategies accordingly. Many researchers do not care about different types of bias and follow general tips to avoid it, but the right approach is to learn about different types and aspects as per the demand of research. Based on the need of hour, you are supposed to work on tips to avoid it. Similarly, when working on the selected type of bias, you must see further details that which of its type is present in your work and accordingly make amendments to the research approach.