What affects recognition most – wrong word stress or wrong word accent?

In an attempt to find out which of the two Swedish prosodic contrasts of 1) word stress pattern and 2) tonal word accent category has the greatest communicative weight, a lexical decision experiment was conducted: in one part word stress pattern was changed from trochaic to iambic, and in the other part trochaic accent II words were changed to accent I. Native Swedish listeners were asked to decide whether the distorted words were real words or ‘non-words’. A clear tendency is that listeners preferred to give more ‘non-word’ responses when the stress pattern was shifted, compared to when word accent category was shifted. This could have implications for priority of phonological features when teaching Swedish as a second language.