Topics 1 & 2: Norms & Reliability {by 6/7}

Based on the text readings and lecture recording due this week consider the following three discussion points: (1) In your own words, provide a general description of the difference between criterion/domain-referenced instruments and norm-referenced instruments. Why is it important to understand this difference? (2) Correlation does not equal causation! Share your thoughts on why this assumption is still a common mistake, especially in the mental health field. (3) Share your thoughts on why reliability is so (wicked) important for psychological assessments (this is a bit of a deep question – give it your best shot).

Your original post should be posted by 6/7. Post your two replies no later than 6/8. *Please remember to click the “reply” button when posting a reply. This makes it easier for the reader to follow the blog postings.

19 Comments (+add yours?)

Kiera Mills
Jun 02, 2025 @ 16:57:48
1. When an instrument is ‘norm-referencing’ this means the test compares one taker’s score to the previous scores. The group of people who took the test in the past is known as the ‘norm’ and can be a large or small population. The individual’s score after taking the instrument is compared to the norm to see how their behaviors or skills match to what is typically expected based on past results. ‘Criterion-referencing’ instruments take an individual’s score and compare it to a preset expectation. This is typically a standard score that shows an ability to perform at a specific level. This does not compare the score to other test takers, only how high or low the score is compared to what is considered mastery of the subject.
2. Correlation is when there is a connection between two separate variables that occur together. Causation is when one variable causes or directly influences another variable to happen. Causation occurs with correlation, but just because variables have a correlation does not mean that one causes the other to happen. This misunderstanding comes from people assuming that if two variables have a relationship then one must cause another instead of just occurring in sync or coincidence. In the mental health field many disorders can be commorid, or occur together, but are still separate disorders. Because they are so common together, like Autism and ADHD, people assume one causes another instead of them just happening to be shown at the same time. Many mental health conditions also do not have a specific cause that can be pointed to as a reason why symptoms have started appearing, making people desperate to find a cause that can be blamed or removed for treatment.
3. The definition of reliability is how consistent the results of an instrument is, making the results expected and able to be repeated upon retesting. If a test is not reliable, the results have no meaning or trust in their accuracy. All instruments have some degree of error, due to external and internal factors, however, if the issues with the test create too many problems that the scores are unreliable then the results cannot be used. If results are completely random, misscored, or inconsistent after several retests then the data cannot tell us any accurate results – they are meaningless if not reliable.
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- Alexis Culver
  Jun 03, 2025 @ 12:19:10
  
  Hi Kiera.
  
  I agree with your answer to question number two that people will just assume one disorder will cause the other just because they are commonly seen together. Also, your answer for question three is very straightforward and I also wrote something similar. There are so many factors that can attribute to a test becoming unreliable.
  
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- Nick Cedeno
  Jun 05, 2025 @ 11:14:42
  
  Hi Kiera!
  
  I appreciated how you mentioned that all instruments have some degree of error. I didn’t even think about this while I was writing my post, but it is an important inclusion because we need to be accurate in what we intended to measure so that accurate results can be reliably replicated. We can replicate a study using the same measure under the same conditions, but if we aren’t measuring what we intended to measure, we lose validity and all we’ve done is replicate the same results using the same measure that inaccurately reflects what you’re trying to communicate. So, the initial choice of instrument that best reflects your goals of what you’re attempting to measure is important as well.
  
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Alexis Culver
Jun 03, 2025 @ 12:15:39
1. A norm referenced instrument is when someone’s scores are compared to other people who have also taken the same instrument. A norm group could be a national sample or it could be a group of your peers in your class. While, a criterion referenced instrument is when someone’s score is compared to a preexisting standard. This means that instead of worrying about how the scores compare to other individuals they are worried about how your score compares to the standard or criteria of the instrument. It is important to understand what the individuals scores are being tested against especially when you are going to report that information back to a client.
2. Correlation is a relationship between two variables where one variable is associated with changes in another variable. While, causation is when one variable directly causes change to another variable. I think since these two definitions are similar people just assume that they are equal. In reality just because something is correlated does not mean there is a direct cause. Two things can be correlated to each other without them being directly caused by one thing. Like in the mental health field a lot of disorders can be paired together so if you say you have one then people might assume you have the other one when that might not be the case.
3. After reading the chapters you begin to understand how important reliability is. When using an instrument to examine someone it is then important to pick the correct reliability instrument to analyze it. If you pick the wrong one then the data could become unreliable. Also, when thinking about how the data is presented if someone scores really high or really low that score could be unreliable just because it is outside the norm or their could be outside reasons for the instrument to be skewed that way.
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- Sydney Corfey
  Jun 03, 2025 @ 17:54:57
  
  Hi Alexis 🙂
  
  I had a similar answer to question 2. I paired eating disorders with anxiety and/or depression as an example. People may assume an individual has anxiety and/or depression if they have an eating disorder which is a misunderstanding and not the case. Your response to question 3 was straightforward and provided good insight. Mentioning using the correct assessment tools and correct reliable instrument for reliable results is a good thing to mention. Good job!
  
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- Kiera Mills
  Jun 03, 2025 @ 20:41:03
  
  Hi Alexis,
  
  I thought that your use of the word ‘association’ when describing correlation was a very good way to describe it. Most people think of relationships between variables as cause and effect, but they can also just be related to one another without causation. My response also mentioned that many mental disorders are paired together without necessarily causing one another, so I agree with you there too.
  
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- Olivia Ago
  Jun 09, 2025 @ 20:34:50
  
  Hi Alexis,
  
  I really enjoyed the example you used in your response to question 2. Co-occurring disorders are so often seen in the mental health field and unfortunately misunderstood for always directly causing one another. This doesn’t account for other factors that can be influencing the development of a disorder, and it also takes away from accurate and sufficient treatment.
  
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Madelyn Messier
Jun 03, 2025 @ 13:31:03
1. Criterion/domain-referenced instruments and norm-referenced instruments are assessment tools. Both of them are used for different purposes. Criterion-referenced instruments measure how well a person performs relative to a fixed criterion or learning standards. An important thing to know is that scores are not compared. For example, when a person takes their driver’s test, they have certain skills that make up the criteria that they have to pass. Norm-referenced instruments are used to compare an individual’s performance to that of a norm group, which is a representative sample of peers. For example, SAT scores are intended to evaluate a student’s performance in relation to a large representative group.
2. Correlation does not equal causation is so true and especially in the mental health field. People often assume that if two things are related, one must be causing the other. For example, someone might think that anxiety causes poor sleep. While that could be true, it’s also possible that both are caused by something else, like unresolved trauma or chronic stress. In mental health, it is important to look at the full picture rather than jumping to conclusions based on surface-level connections. Without considering other underlying factors, we risk misunderstanding what is really going on and potentially using the wrong approach to treatment.
3. Reliability is wickedly important in psychological assessments because it ensures that the results are consistent and dependable over time. Without reliability, we can’t trust the accuracy of the assessment, which can lead to serious consequences like misdiagnosis. An unreliable test might label someone with the wrong condition, causing clinicians to choose ineffective or even harmful treatments. This not only delays proper care but can also damage the client’s trust in therapy. In a field where decisions deeply affect people’s mental health and well-being, having consistent and trustworthy tools is important.
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- Sydney Corfey
  Jun 03, 2025 @ 17:49:30
  
  Hi Madelyn 🙂
  
  The misunderstanding with correlation and causation can cause many misdiagnosis and incorrect treatment plans. The risk of using the wrong approach and misdiagnosing is extreme with the misunderstanding. Also, reliability is extremely important because the results need to be dependable and consistent so we can properly diagnose the individual and provide the best treatment possible for them. With unreliable results, we risk misdiagnosing someone and giving improper treatment which can/will worsen their case. Everything you stated is important to know and keep in mind for the future. Good job!
  
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- Nick Cedeno
  Jun 05, 2025 @ 11:09:47
  
  Hi Maddy!
  
  The SAT example was a good one to provide further insight into the difference between norm referenced instruments vs. criterion/domain-referenced instruments. For me, these kinds of examples allow me to better understand the purpose of the instruments in a practical context. I also appreciated how you explained correlation vs. causation. It made me think about how we were talking about the DSM-5-TR as a supplemental guide to help make decisions, instead of the end-all-be-all of your decision making process. By that, I mean that the DSM-5-TR can be a helpful guide is understanding an individual by making some correlations with the presenting symptoms, but getting the individual’s full context is important for getting a complete picture of the individual’s history to make a better informed decision that allows us to be more confident in the relationship between the variables.
  
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Sydney Corfey
Jun 03, 2025 @ 17:45:23
1. A norm-referenced instrument is when an individual’s score is compared to other scores of other individuals who have taken the same instrument. A criterion-referenced instrument is when an individual’s score is compared to the criterion or the established standard. The norm-referenced instrument is considered the “normal” or “average outcome” of all the scores when compared. These are both assessment tools and the major difference between the two is the criterion-referenced instrument does not have the individual’s score compared to other’s, but rather compared it to the established standard score. This is important to understand because it helps establish the ability of the individual regarding the criterion of the instrument.
2. Correlation is when there is a relationship between two variables. Causation is when one variable causes change or influence in another variable. Throughout statistics in undergrad, my professor emphasized that correlation does not equal causation, but some individuals still make this mistake. There is a misunderstanding that two variables having a relationship together means one variable MUST be influenced by the other. In the mental field, many individuals think one disorder causes the other. For example, many individuals with eating disorders also have anxiety and/or depression. People may believe the eating disorder causes the anxiety and/or depression when in reality, that is not the cause and can cause possible wrong ways of treatment.
3. Reliability is so WICKED important for psychological assessment because it confirms that the results are dependable which helps with proper diagnosis. With unreliable results, it could lead to misdiagnosis and an incorrect treatment plan. With diagnosis, it’s important to have reliable results that emphasize dependence and consistency so the individual can be properly diagnosed and given the proper treatment plan for their diagnosis.
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- Kiera Mills
  Jun 03, 2025 @ 20:35:18
  
  Hi Sydney,
  
  I liked how you mentioned that patients can receive an inaccurate diagnosis when given unreliable assessments. My response had focused on the data itself being unreliable so it gave me a new perspective that the bigger issue is the results coming from that data being inaccurate can cause issues in treatment. I think I had thought of reliability in a research sense and you thought of it in a clinical context which I appreciate.
  
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- Alexis Culver
  Jun 04, 2025 @ 08:46:02
  
  Hi Sydney,
  
  I had a similar answer to question 2 I did not give a direct example but your example is a very good way of explaining it. It is hard for some to differentiate especially when they have not been exposed to those terms before. Your question 3 was very insightful but also very true if the individual used an unreliable result then their clients treatment would not be correct. Good Job!
  
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- Madelyn Messier
  Jun 06, 2025 @ 14:21:03
  
  Hi Sydney,
  
  I had a similar response to question 3. If an assessment isn’t reliable, we can’t trust it to give us consistent results. And without that consistency, it’s really hard to make an accurate diagnosis. That would be a big problem, because if the diagnosis is off, the treatment plan will be too, which could seriously affect someone’s care.
  
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Nick Cedeno
Jun 05, 2025 @ 10:04:51
1. A norm-referencing sample is when a particular individual’s score is directly compared to the scores of other individuals to obtain some information on the individual’s level of performance compared to the “normal” or “average” performance. We can gauge how well this person may be able to generally perform. The “norm” is represented by the average score of the other individuals who used the same measurement instrument. This is differentiated from criterion or domain referenced instruments in that criterion referenced instruments compare the individual’s performance to a predetermined standard or criterion. This can reflect a more specific performance in a particular skill or setting. This also has the ability to more accurately reflect mastery. This distinction is important to make because, depending on the context of the situation, one instrument may be more appropriate to use than the other.
2. Correlation is when two variables occur together, but it is not certain that one variable directly causes the other. Causation is when two variables occur together, and we are confident that one variable causes the other. Sometimes, the assumption that two variables occurring together means that they caused each other. This could be misleading in that the assumption could lead to someone to draw conclusions or causal relationships that don’t exist. This is important for the mental health field because when two variables present themselves in an instance, it is possible that hasty conclusions could be drawn. For example, if there is a situation where multiple diagnosis could be applied, there could be comorbidity taking place and any assumptions of once variable causing the other could be potentially misleading.
3. Reliability is important to reflect the consistency in your results. The more reliable your results are, the more confidence people have in them. If you ensure that you are measuring what you intended to measure (validity) and you produce results that are consistent under the same conditions, you can achieve reliability. This is important in psychological assessments because one result may be misleading in that the instrument used wasn’t valid so when we go to replicate the results with a different (more applicable) instrument, the results differ. We no longer have reliability. If we use the right instrument and are able to replicate the same conditions, we can accurately and reliably produce results.
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- Madelyn Messier
  Jun 06, 2025 @ 14:04:46
  
  Hi Nick,
  
  You brought up a really important point about not confusing correlation with causation. For example anxiety and depression are often diagnosed together, and many of their symptoms overlap. Like trouble sleeping, difficulty concentrating, and low energy. Because of this, it’s common to see both conditions present at the same time, which makes it even more important not to assume one is causing the other without a deeper assessment.
  
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Xhesika Halili
Jun 06, 2025 @ 23:44:22
1. The norm referenced instrument refers an individual’s score or performance compared with others individual’s performance who taken the same instrument. The norming group can be a large group, or fellow classmates. Example if someone take a BDI a client’s score it will be compared to average depression levels in populationIn a criterion-referenced instrument the individual’s score is compared with criterion. Sometimes criterion referenced instrument called objective referenced. Example if you take 70% in a test you pass the test and doesn’t matter how others did
2. Correlation shows how two sets of variables are related to each other. It is often used to check how consistent something is, but it can also be used in many other ways to look at relationships between variables. However, correlation does not mean that one thing causes the other. This is because correlation does not take into account other factors that might be influencing the results at the same time. Even if one thing causes the other, correlation doesn’t tell us wich one causes wich.
3. Reliability concerns the degree to wich scores on the instrument are consistent and the degree to wich those scores may be influenced by error. Reliability is crucially because is the foundation of trust in the result. Psychology is science that try to be evidence based, without reliability the data loses credibility.
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- Olivia Ago
  Jun 09, 2025 @ 20:27:30
  
  Hi Xhesika,
  
  You brought up such a good point on how results can be influenced by error and how reliability relates to the credibility of evidence-based science! I think it’s so important to consider whether results can be backed up by evidence that is relevant to what is being assessed, and reliability allows us to have trust in instruments that further support our understanding of an individual.
  
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Olivia Ago
Jun 09, 2025 @ 20:22:07
1. Norm-referenced instruments compare an individual score with other individual scores after use of the same instrument. This allows for those assessing the scores to determine possible ranks among the individuals based on their scoring or performance compared to one another. Criterion/domain-referenced instruments compare an individual score with a predetermined standard of what is expected to be scored. By having an expectation of standard performance within criterion-referenced instruments, there is often a component of mastery that is expected to be reached in order to have successfully completed the instrument. It is incredibly important to understand the difference between norm-referenced instruments and criterion-referenced instruments as it pertains to how we assess the information collected from the comparison of scores. When we compare scores through norm-referenced instruments, this gives insight to the impact of individual differences among test-takers and how well they do in relation to others taking the same assessment. However norm-referenced instruments do not account for whether the individual adequately understands the material that is being assessed. Whereas criterion-referenced instruments solely relies on an individual reaching a certain cut-off, and does not account for how successful the individual was in the assessment in relation to others. By understanding the difference among these two instruments, we are better able to interpret the results of an assessment through the context in which they are relevant.
2. I think that the common misconception that correlation is an interchangeable term for causation stems from a lack of education or wide-spread understanding of the two terms and the significance in their difference when it comes to assessing relationships among two variables, particularly when it comes to mental health. When a correlation between two variables is found, people often jump to the conclusion that these two variables have a direct influence on one another, but often do not account for the direction of the correlation or whether there are other variables that are influencing that correlation. In my undergraduate program, the example of ice cream sales and murder rates was often used to highlight the importance of this distinction. Although ice cream sales are positively correlated with murder rates, this is not because one variable is directly influenced by another. The confounding variables of heat and aggression impact these results, as with an increase in temperatures in the summer correlates with an increase in ice cream sales and aggression levels, which correlates with murder rates. This example highlights why the context of the correlation matters greatly, and just because two variables seem to be influenced by one another, does not mean they are a direct cause.
3. Reliability is important for psychological assessments as it indicates whether the results of an assessment are consistent and dependable. When psychological assessments are consistent and dependable, they are able to be effectively used for treatment planning and better understanding of diagnoses. If the results of a psychological assessment are inconsistent, the conclusions made from that assessment are less meaningful than results that are consistent throughout, and this would be unhelpful in determining mental health diagnoses or possible directions for treatment.
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Dr. Adam M Volungis