What Is Reliability Psychology And How It Affects Mental Health Treatment

In psychology, there are many unique concepts that you should know if you want to understand the full picture of psychology. In this article, we will be looking at what reliability means in the psychological context. Officially, reliability in psychology refers to how trustworthy or consistent results are in a research study. If you are not a research scientist, you may not understand why this is important and how unreliable results in studies can affect someone. Let’s find out.

Why is reliability important?

In the context of psychology, reliability is used during a study to measure its consistency. You may wonder why this is important in the context of seeking therapy. However, mental health professionals, like therapists, use the trustworthiness of psychological studies to improve their ability to understand and treat their patients. Furthermore, therapists and psychologists will often use assessment tests that have been shown reliable to analyze and diagnose their patients.

Without reliability, there is no consistent details, and the results are not reproducible. In any scientific test, one must have consistency if they want the test to live up to scrutiny. Let’s compare it to measuring your height. The measuring tape that you use to measure your height will have inches measured in the same way each time. What if every time you took out the tape, the length of the inches was different? The tape would be unreliable. The same would happen if you weighed yourself on a scale that gave you radically different readings each time.

When you are conducting a study, like in the previous example of measuring height, contradictory results lead to confusion and invalidation of the research. For example, if you are studying the effects of medicine on someone, the effects it has should be mostly consistent each time you test or review the results. When there is no reliable pattern in the medicine’s activity, then there is no way to conclude that it works.  

Continuing with the medicine comparison, there are some cases where the results will be different, as people will react to the medicine differently in some cases. Consistency does not mean that it will happen every time, but it will happen reliably, and that’s the point.

The following section explores the different types of reliability and their application to real-life psychology. 

Types of reliability

Psychologists and psychiatrist use several psychological measures to assess their clients, including personality or cognitive tests and clinical interviews. These measures help to confirm that a test or questionnaire given to a patient is worthy of confirming an internal condition or behavior and must be reliable. 

When psychology researchers discuss the measures of reliability in a study or test, they typically refer to two types, internal and external. 

Internal reliability

Internal reliability will assess how consistent the results are within the test itself. By test, we mean those used to measure one’s psychology, such as questionnaires. It will look at the parts of a test and see which ones will contribute in an equal manner.

The way researchers assess this is by using the split-half method. By using this method, the test authors can confirm that each part of the study contributes equally to what is being measured. 

Split-half method

The split-half method is done by looking at the two halves of a test and comparing how they worked. You can split a test in two using different methods. You can number it, or just cut it in two. These two halves should give you similar results. This will prove the internal reliability of a test.

How reliable a test is can be improved by this split-half method. You can get rid of parts of the test that have a low level of correlation, or at least revise the factors until all parts of the test have the same amount of consistency.

One drawback of the split-half method is that the test needs to be large and have similar questions throughout the test. If different constructs are used to measure individual questions, this could mean the reliability of the test is lower.

Let’s look at the Minnesota Multiphasic Personality Inventory (MMPI) as an example. The MMPI is the most commonly used psychometric test used to measure both personality and psychopathology. There are 567 true or false questions in the test that are plotted on a graph. This is test is complex and includes unique scales to measure all the factors that may contribute to a mental health diagnosis (i.e., depression, schizophrenia, etc.). Because of the complexity of measures, the split-half method is unable to accurately break down the results and not applicable to testing reliability for this inventory test. 

External reliability

In external reliability, we measure the extent of the variables to see how they work. External reliability has its own method, and this is called the test-retest method.

Test-retest is used to measure the consistency of the external factors of a test. Like split half, this may deal with questionnaires and makes sure a test is measured consistently over time so that there is minimal room for errors.

When it comes to test-retest, let’s look at your typical assessment. You may give the subjects the same test but do it twice on different occasions. Then, you can compare both results. If the results are the same, then you will establish external reliability. Test-retest can verify if factors have revealed why the results may be similar or different. However, there is a disadvantage to the test-retest method, and that’s the fact that there is a time gap between obtaining results.

Test-retest is currently being used to determine the reliability of computerized test batteries - a series of tests that assess the efficacy of pharmacological interventions on cognitive function.  Thomas et al., determined that these electronic tests were reliable using the external test-retest method.

This helps us understand how necessary test-retest is in the world of diagnosis. If the reliability was not there, some people may not be diagnosed or misdiagnosed and pharmacological interventions cannot be measured accurately for efficacy.  This test assures that clients will have accurate and effective treatment available to them. 

Inter-rater reliability

Inter-rater reliability is another method that measures how externally reliable a test is by observing the people giving the test. This method measures the consistency of the raters conducting the test to determine if the same estimates of behaviors are similar. This is useful for interviews and other types of qualitative studies.

This can also be known as inter-observer reliability in the context of observational research. 

When there is no correlation in observer scores, you can improve reliability by operationalizing behavior categories and make sure they are quantifiable. In other words, you need to make sure these methods have been defined as objectively as possible. Then, you can train observers in the techniques used for observation. You need to look at the observers and see if everyone agrees to those terms. If not, you should reevaluate your testing criteria.

Let’s look at the concept of two researchers who are looking at children’s behavior that is aggressive. They are observing behavior at a nursery, and they may have their own opinions on aggression. This situation could lead to them not be recording the child’s aggressive behavior similarly. They can accomplish operationalizing the behavior of aggression by making it more objective. This is because it’s much easier to look for specific behaviors rather than a broad range of behaviors that are not defined.

The term “aggressive behavior” is quite vague and subjective. Is getting irritated aggressive? Is some horseplay aggressive? There is no right or wrong answer. However, if you categorize specific behaviors as aggressive, it’s much easier to find the results. For example, the behavior listed may be “pushing.” By listing the behavior like that, the researchers are now looking for when children push one another. This makes it much, much easier for the observer to find signs of pushing.

In any study, it is imperative to have clarity. Studies where the subject matter is vague, will yield results that may be all over the place, making the study less useful. 

Seeking professional advice

Are you interested in learning more about your own psychology? Therapy is an ideal place for you to discover why you are managing repetitive thoughts and behaviors that are affecting your daily life. You may also simply be interested in understanding your personality and thinking patterns. Before you decide on a therapist, be sure you choose one you trust and with whom you feel most comfortable. There are several options available to you and finding the right fit may take some trial and error. 

When it comes to formats, you can choose between in-person or virtual therapy. Both are equally effective in supporting mental health. For example, a recent study examined the efficacy of online therapy in comparison with in-person therapy – a vitally important study that occurred during the pandemic when people lost contact to mental health care. Through online cognitive behavioral therapy, over 6,000 people in the study reported their symptoms of anxiety and depression improved, with marked reduction in psychological distress. Without effective reliability measures in place, the study authors would not have been able to measure the effectiveness of their treatment. 

Mental health professionals are available through the online platform at MyTherapist.com to help get you started. Here counselors can be available via phone call, video call, and/or online chat. Whichever format you choose, know you will be able to get  treatment in the comfort of your own home and according to your own schedule. 

Takeaway

Those involved in the world of psychology know that its core is rooted in observing the intricated processes of the mind and brain in hopes of improving mental health. Because of this, there needs to be strict criteria in measuring how reliable studies and tests are before they are used in healthcare. Reliable measures in psychological research contribute to the expansion of knowledge in the field while improving the quality of care and effective treatment methods for those seeking excellent mental health care. If you are looking to learn more about yourself through therapy, consider reaching for an online mental health therapist. They are available to guide you in self-awareness and self-discovery and are trained in reliable methods in psychology.