¶ … exercises improve critical thinking skills?, Cotter and Tally take a closer look at how effective the teaching of critical thinking skills actually is. They had students complete a number of different tests. The authors noted that while there was a correlation between the scores of the different tests, that these scores and the correlation did not improve over the course of the semester. They suggest that "critical thinking assignments did not have a positive effect on either formal thought or critical thinking skills." So the authors here are investigating the idea that teaching critical thinking skills needs to be tested against actual outcomes that would demonstrate improvements in critical thinking skills. They sought to basically examine this by studying the issue on a before-and-after basis.

The literature review covers a variety of subjects. It begins with a definition of critical thinking, which includes "evaluating the sources of information, challenging assumptions, understanding context, analyzing arguments and using metacognition." They cite several articles that discuss different ways to measure critical thinking skills. This literature exists because of the educational field, where critical thinking skills have been taught and there is a need to measure the effectiveness of these teaching techniques.

This literature is also presented by the authors. The material dates back to the 1970s but most of it is from the 1980s. So the field of critical thinking is actually a relatively new field, and this is why these authors are just now starting to take a look at how effective critical thinking teaching is. Their literature review does not spend much time on this particular subject, perhaps indicating that there is a lack of research on the subject entirely.
Measurement

In terms of measurement, the California Critical Thinking Skills Test was used. This test has 34 multiple choice questions that "measure interpretation, analysis, inference, explanation, self-regulation and evaluation." The authors note that these skills are consistent with the American Psychological Association's definition of critical thinking. This creates a direct link between the choice of measures and the skills that are being tested. This is not a sloppy proxy, this is an accurate assessment using tests that have been proven in the past.

The students were allowed to choose the assignments that they completed, and these assignments were graded based on writing mechanics,…