Have you used Kepner-Tregoe Method?

Tamer, it is Problem Solving and Decision Making (PSDM).
There are four basic steps when using the Kepner Tregoe decision matrix:

Situation appraisal - is used to clarify the situation, outline concerns and choose a direction

Problem analysis - here the problem is defined and it's root cause determined

Decision analysis - alternatives are identified and a risk analysis done for each

Potential problem analysis - the best of the alternatives is further scrutinized against potential problems and negative consequences and actions are proposed to minimize the risk.

Following the step-by-step approach of Kepner Tregoe decision making allows for the use of critical thinking skills in considering many possible factors that may be vital in making the decision.