Internal Validity in Research
Internal validity can be referred to as a technique that you could apply for measuring the effectiveness of research. Ph.D. scholars often have issues in measuring the internal validity of the research. In this article, the professional team of Ireland’s assignment help is providing a detailed explanation of internal validity in research.
Internal validity in research is basically a level of confidence that the test which you have performed for judging the causal relationship between variables is reliable. It is considered to be one of the important measures, particularly in Quantitative research. An internal validity helps in making sure that the experiment design which the researcher has to choose properly follows the principle of cause and effect. It is very crucial for you to consider internal validity, particularly in scientific and social science research.
One of the best ways of describing internal validity is to demonstrate confidence in relation to the relationship between cause and effect. For example, an experiment in the field of physics has been conducted to analyze the influence of heat on the conductivity of metal which is considered to be as high internal validity.
An investigator can eliminate almost all of the potential confusing variables and could establish strong control to isolate other variables.
Internal validity: Examples
Example 1: An investigation performs for analyzing the relationship between income level and the likelihood of smoking has lower internal validity. It has been found from research that there is a relationship between smoking and low-income group. For example the different types of variables are profession, ethnicity, education, social status, etc. You can not eliminate such variables from the study. It is internal validity which helps in demonstrating that you have evidence that proves that findings have a significant influence on results.
Example 2: An investigator performs research for analyzing the influence of computer programs specially designed for teaching on traditional classroom teaching techniques. The finding of the study reveals that children who are taught using computer program learn quickly. Another thing which has been discovered from the research is that due to computerized teaching there has been great improvement in grades of children. However, research that other investigators perform reveals that children who are taught using the computer program feels that they are not gaining attention. An experiment still represents high internal validity, as study manipulation has influence. But investigations perform for research paper has low construct validity, as the cause is not clearly stated. A researcher mainly emphasizes attention rather than the benefit of computer programs.
How to maintain the internal validity of the study?
You can’t have confidence in experimental design, as there are high chances of error. There are a number of tools which researcher can utilize for confirming the internal validity of the study and establishing causality. These tools are:
- Temporal precedence: It is considered as one of the crucial tools which help you in determining the relationship between cause and effect. It is the procedure that includes the establishment of the cause which takes place before effect.
- Covariation of cause and effect: Covariation of cause and effect is basically a procedure that mainly includes the establishment of the fact that there is a relationship between different variables. It is the element that helps you in demonstrating that findings of research on the specific topic have some kind of influence that you can measure.
For example: An investigator has performed an investigation for analyzing the learning capability of Greek students. The findings of study represent that students who were taught using computer programs learn in better manner. It means that if you utilize the computer outcome it will help you in generating positive outcomes. In case, a computer program is not utilized by the researcher that means there will no outcome.
- Establishing causality through a procedure of elimination: It is considered to be s one of the best techniques to demonstrate the internal validity of your study. As in the above example, you can give many explanations for proving the relationship between student learning and computer program. Strong experimental research design can help you in finding the missing variable. Some of the techniques which you can use for eliminating the confounding variables are randomization, repeat experiments and control groups. These tools or techniques you can use for maintaining high validity.
What factors can affect the internal validity of the study?
The 7 factors which can threat to the internal validity of research are:
|Confounding factors||An unexpected variable that influences the causal relationship is tested in the study.||The company can appoint a new manager during the duration of research which will help them in improving the job satisfaction level.|
|Maturation||The change in time has a significant influence on the dependent variable.||At the time of investigation which the researcher has performed, employees have gained more experience and have been able to perform well at the workplace which has lead to an increase in job satisfaction level.|
|Testing||The pre-test which you perform has a significant influence on outcomes of the post-tests.||You need to make sure that workers maintain consistency in answering Questions during both pre and post-test.|
|Selection of participants||There can be substantial differences between participants in experimental research.||You can select participants voluntarily and influence them to participate in experiments.|
|Mortality||In case you perform a longer investigation for writing the research paper, there are high chances that participants will quit in between. If the experimental treatment is the main cause it can create a threat to the internal validity of the study.||Employees who are highly dissatisfied will leave the job. It will result in an improvement in an average job satisfaction level. Unsatisfied workers are not selected for the post-test.|
|Regression towards mean||The acute score is considering close to the average of the second measurement.||Research performs for analyzing the influence of low scores on employees’ satisfaction levels. Findings of research reveal that workers those who got low score has a low satisfaction level as compared to employees with a high score.|
|Instrumentation||The modification takes place in such a manner how you measure dependent variables during the study.||The questionnaire consists of extra questions that are then compared to one main question that has been utilized for the pre-test.|