Are the prayers performed with doubt about the predominant assumption during scrupulous whispering (waswasah) invalid, and without determining the procedure before proceeding with the prayer?

The person afflicted with intrusive thoughts (waswasa) should dismiss the doubt and not act upon it, and he is not required to perform the prostration of forgetfulness (sujud (definition) al-sahw). If he dismisses the doubt while experiencing his intrusive thoughts, then he has done what is required of him, his prayer is valid, and he is not obliged to repeat it. The saying of the Sheikh: "And doubt after the action has no effect... and similarly if doubts multiply" applies to the normal person who is not afflicted with intrusive thoughts.