I am planning a regression analysis where a continuous independent variable predicts 3 categorical outcomes of a dependent variable. I believe this is done using multinomial logistic regression. Before I go ahead and collect my data I would like to get an idea of the sample size I will need to to have an adequately powered analysis. I have not been able to find much information about how to conduct a power analysis for a multinomial logistic regression. My questions are as follows: A) is a multinomial logistic regression the right statistic for this scenario? And B) if so, how to conduct a power analysis for multinomial regression?

I am planning a regression analysis where a continuous independent variable predicts 3 categorical outcomes of a dependent variable. I believe this is done using multinomial logistic regression. Before I go ahead and collect my data I would like to get an idea of the sample size I will need to to have an adequately powered analysis. I have not been able to find much information about how to conduct a power analysis for a multinomial logistic regression. 

My questions are as follows:

1. is a multinomial logistic regression the right statistic for this scenario?
2. if so, how to conduct a power analysis for multinomial regression?