Garrison developed a theory of critical thinking, as a kind of problem-solving process (Garrison 1992). Critical thinkers move through 5 stages, identifying a problem, defining it more clearly, exploring the problem and possible solutions, evaluating their applicability, and then integrating this understanding with existing knowledge. Although he initially developed it as a means of studying individual distance learners, it is well suited to the analysis of critical thinking within group learning, since these same stages are followed.
Henri (1991) identified five dimensions for analysing Computer-Mediated Communication (CMC): participative, social, interactive, cognitive and metacognitive. Questions of deep learning and critical thinking are in the cognitive dimension, so we concentrated on that. She laid out 5 skills needed for critical reasoning. It turns out that each skill is used mainly in one of Garrison's stages, as Table 1 shows.
| Garrison's CT stages | Henri's critical reasoning skills |
|---|---|
| 1. Problem identification a triggering event arouses interest in a problem | Elementary clarification observing or studying a problem, identifying its elements, observing their linkages |
| 2. Problem definition define problem boundaries, ends and means | In-depth clarification analysing a problem to understand its underlying values, beliefs and assumptions |
| 3. Problem exploration ability to see to heart of problem based on deep understanding of situation | Inference admitting or proposing an idea based on links to admittedly true propositions |
| 4. Problem applicability evaluation of alternative solutions and new ideas | Judgement making decisions, evaluations and criticisms |
| 5. Problem integration acting upon understanding to validate knowledge | Strategies for application of solution following on choice or decision |
For each stage, Garrison, Henri and us identified indicators that showed (or at least suggested) critical thinking was taking place. For the content analysis, we picked pairs of indicators: a +ve indicator, showing evidence of critical thinking, and a -ve indicator, showing its opposite (e.g. uncritical acceptance or denial, deviations from the subject). These are discussed in detail in the earlier paper, and listed in Appendix A, where we show how we think they map into Garrison's 5 stages of critical thinking.