Quality thinking is a system of judgments, which is used to analyze things and events with the formulation of valid conclusions and allows you to make informed assessment, interpretation, and correctly apply these results to situations and problems. In a general sense the quality thinking involves a higher level of thinking than thinking inequality.(Dettmer 2007)
As I have understood, the major basics that form a set of core skills required for quality thinking consists of: observation, ability to interpret, analyze, make findings, the ability to make evaluations. Quality thinking applies logic, and also relies on meta-knowledge and broad criteria of intelligence, such as clarity, credibility, accuracy, relevance, depth outlook and justice. Creative imagination, values, and in a lesser extent expressed emotion, is also part of quality thinking.
On of the most importing factors to evaluate the quality of one’s thinking is to check person's ability not to get influenced by the opinions of others, to objectively assess the positive and negative aspects of the phenomenon, to understand what is valuable and what is not.
Man with a critical mind demandingly evaluates his views, carefully examines solutions, weighing all the arguments "for" and "against", showing the self-critical attitude to their own actions.
As for me, it is both not hard to evaluate my own quality of thinking and quality of thinking of people that surround me. Of course, evaluating quality of thinking of others is much more easier job to do. It is easier to make conclusions about other people you contact with. You can give mark to their statements and their goals, the solutions they suggest for resolving this or that issue. And when it comes to evaluating your own thinking, it is more complicated, because the fact that you understand yourself, understanding what is the issue, where it comes from and where it goes, does not actually mean that the majority of people will properly understand you statements and conclusions.
References
Dettmer, H. (2007). The logical thinking process. Milwaukee, Wis.: ASQ Quality Press.