Irrelevant Variance of Test Items: Making Items Fair It s all about increasing reliability by decreasing irrelevant variance Linda Caputi, MSN, EdD, RN, ANEF, CNE Reliabilty What is irrelevant variance? Reliability refers to the test providing consistent results that are reproducible and generalizable. Irrelevant variance interferes with reliability. Causes of test results to vary among students. The ONE relevant variance you are testing for is: Which students know the material and know how to use the material at the cognitive level of the test item. What is irrelevant variance? Some sources of irrelevant variance: Cheating Item bias Test-wise items Ambiguous test items: Poorly written test items: the student is unable to understand the test question or misunderstands. Importance of Reliability The overall reliability of an exam. Directly reflects the level of confidence you can have in an exam and the decisions that can be made based on an exam. 1
What is linguistic modification and how does it decrease irrelevant variance? Exams should test the student s knowledge & application of nursing not mastery of complex language Especially helpful for ELL but helpful to all students Apply linguistic modification to reduce the language complexity NCLEX-RN is written at the 11 th grade level Does not affect the content & integrity of the items. NCLEX-PN is written at the 10 th grade level Reduces threats to the reliability and validity of test scores Write with clear language and free of unnecessary complexity Example Revision Which of the following will a nurse teach to a patient with chronic obstructive pulmonary disease to empty the lungs of used air and promote inhalation of oxygen? A nurse is teaching a patient with chronic obstructive pulmonary disease. What breathing technique will help the patient empty the lungs of used air and increase intake of oxygen? 2
Simpler Example The nurse is working on a medical unit. Which of the following nursing tasks would be best to delegate to a nursing assistant? 1. Skin care for a patient with a reddened sacrum. 2. Urinary catheterization for a patient with benign prostatic hypertrophy. 3. G-tube feeding for a patient with an acute episode of schizophrenia. 4. Discharge teaching for a patient with liver disease secondary to alcoholism. Revision The nurse is working on a medical unit. Which task will the nurse delegate to the nursing assistant? 1. Skin care for a patient with a reddened sacrum. 2. Urinary catheterization for a patient with benign prostatic hypertrophy. 3. G-tube feeding for a patient with an acute episode of schizophrenia. 4. Discharge teaching for a patient with liver disease secondary to alcoholism. Refers to revising test items to decrease the reading load that is the amount of effort required to understand the language. Results in linguistic simplification: key content area vocabulary and terms are maintained, but the semantic and syntactic complexity of the English is reduced. Refers to modifying test questions to reduce unnecessary language complexity Low-frequency of word usage Long, complex words Long sentences Passive voice Long noun phrases Long question phrases Long questions with complex language Example: Passive Voice A patient who had a cholecystectomy yesterday has been assessed by the nurse. Which finding should be followed up by the nurse? The nurse is assessing a patient who had a cholecystectomy yesterday. Which finding requires action by the nurse? 3
Complicated Language Which of the following suggestions by the nurse has the greatest potential for minimizing the patient's risk for fall related to visual The nurse is working with a patient who is visually impaired. What will the nurse suggest to decrease the patient s risk for fall? problems? Simpler Language The student reads a brief scenario then is asked: Which of the following does this information suggest to the nurse? Simpler language would be: What decision will the nurse make based on this information? Use shorter, simpler sentences rather than longer, more complex sentences. Use questions rather than completion format unless the completion format simplifies the reading; if so, only use this type of construction occasionally. Highlight key words such as most, best, and first. Maybe just for the first few courses. Use more common words rather than less frequently used words such as first rather than initially. Or, In which situation should the nurse have a high index of suspicion for water intoxication? Change to: In which situation does the nurse suspect water intoxication? 4
Eliminate the words "Of the following." These are unnecessary words. Avoid the use of pronouns; they can be confusing. Don't use the word appropriate such as Most appropriate. This is a vague phrase that is misleading, and what is appropriate for one person may not be appropriate for another. Just ask, "What action will the nurse take" or "What will the nurse do next?" Thank you for previewing. For a detailed, indepth workshop on test item writing and many other topics please visit my website at: www.lindacaputi.com The End I also provide consulting services related to accreditation, revising/writing curriculum, increasing NCLEX pass rates and many other topics. 5