How to preapre a questionnaire for market research?

hi all. I am doing a project with a medical devices company. I need to ffind out why the competition products are selling. need to prepare a questionnaire. how should i go abt that. which questions shoiuld i ask

How to preapre a questionnaire for market research?
as far as I learned form your question you are interested to know why a product of your competitor are selling well.


so you are going to preper a questionair to find out the reason. ok. if it is the case you can put following questions:( you shall ask buyer.


1- why you have chose this product?


2- which specifications of this product has convinsed you to buy?


3- have you studied specification of other products?


4- what kind of terms and conditions of supplier of this product has convinced you to choose this product.


5- which factors has the most influces in you buying decision ( price, delivery time ,quality and name of supplier)?


6- are you going to buy again from this supplier?


7-which characteristics of others product has removed you from buying those product?


and any other questions which will reveal some aspect of product of your competitor. by the way you shall also make a difference between buyer and user. who make buying decision? purchasing department or the one who use this device?





regards


Omid