title: Can I use Chi-Square Test for the change score analysis?
body: <p>For example, if I have a pre-post design experiment with 2 groups A and B. I can get change scores(Post minus Pre). And I can count the number of positive changes and negative changes. Hence I create a table:</p>
  <pre><code>                            A                B
  Positive Change Score      n1                n2
  Negative Change Score      n3                n4
  </code></pre>
  <p>Then can I use Chi-Square Test?
  I have learned that ANCOVA is a better choice, but the change scores violate normality test assumptions so maybe ANCOVA is not a good one.</p>