It sounds like you want to do what is known in mixed methods research as an exploratory sequential design. In other words, you main goal is to develop a protocol, and you are using a preliminary qualitative method to do that (qual --> QUAN).

This is a very common design in mixed methods, and integration is straight forward, baaed on your conversion of the qualitative data into its implications for your protocol.

@David L Morgan , sir

Thank you for your response but Nominal Group Technique is it self s mixup, like semi quali + semi quantity, we converting quali into quanti results by voting responses and ranking. How do we justify as these results are coming after quantitative means.

If all you did was nominal groups, then I personally would not call that mixed methods. For me, mixed methods research requires both qualitative and quantitative results, with an integration of the two.

@David L Morgan ,that's exactly I am asking , what we call this design then if it's not a mixed