I am conducting research into the impacts of three independent variables; speaker type, task difficulty, and task format, on the oral speech production of language learners. There are four dependent variables measured; frequency of mid pauses, frequency of end pauses, average number of pauses, and average pause length.

Data has been coded and collected, extreme outliers were removed, and all the dependent variables show reasonable normality of variance, with little skewness or kurtosis. Analysis was conducted in R and Q-Q plots were generated for each dependent variable separately for each of the three independent variables. The data set comprises 80 participants (40 of each speaker type) who each provided two speech samples, so a total of 160 different tasks.

I am now trying to decide which statistical analysis to employ to show me clearly the impacts of task complexity (IV) on the pause frequency, and pause length etc. (DVs) but also differentiated by speaker type (IV), and task format (IV). Would it be better to run separate one way ANOVAs for each IV or could they be combined into one statistical test? I have been doing most of my analysis using R if that matters.

Thanks for taking the time to read this and hopefully it is clear, if not I apologise and please ask any questions you like.