Reliability

1. Test–Retest or Stability

1.1. “Test –retest is a method of estimating reliability that is exactly what its name implies” (Kubiszyn 341).

2. Alternate Forms or Equivalence

2.1. “If there are two equivalent forms of a test, these forms can be used to obtain an estimate of the reliability of the scores from the test” (Kubiszyn 343).

3. Internal Consistency

3.1. “If the test in question is designed to measure a single basic concept, it is reasonable to assume that people who get one item right will be more likely to get other, similar items right” (Kubiszyn 343).

3.2. Split-half methods

3.2.1. "To find the split-half (or odd–even) reliability, each item is assigned to one half or the other" (Kubiszyn 343)

3.3. Kuder–Richardson methods

3.3.1. "These methods measure the extent to which items within one form of the test have as much in common with one another as do the items in that one form with corresponding items in an equivalent form" (Kubiszyn 344)