After a person has been diagnosed with schizophrenia in a family, the chance for a sibling to also be diagnosed with schizophrenia is 7 to 9 percent. If a parent has schizophrenia, the chance for a child to have the disorder is 10 to 15 percent. Over 250,000 diagnosed cases in Britain. 2  Rates of schizophrenia are generally similar from country to countryabout .5% to 1 percent of the population (there are variations-but the variance is difficult to track due to differing measuring standards in many countries, etc.).
View Full Document. Test Bias â A test bias is a systematic difference in the meaning of test scores amongst different groups. There are internal and external ways to identify test score bias. Test Fairness â This refers to how a test is used.
Norms allow you to compare your test scores with others. So, instead of just knowing that you got a 100 on the test, you could also be told that a score of 100 is at the 50th percentile. That tells you that roughly half of the people who are in the same group as you scored higher and lower than you did.any psychological tests, including intelligence tests, are about comparing your score to others' scores to see how you did. Watch this lesson to find out about two important concepts in psychology: standardization and norms.