One study compares two rehearsal methods: shadowing and repeating. Results showed that the shadowing group improved shadowing and repeating skills, while the repeating group didn't enhance either skill. It was also found that shadowing had a weaker correlation with written test scores than repeating, both pre- and post-treatment.
Another study compares repeating and consecutive interpreting during pauses. The results showed that the repeating group improved repeating skill, while the consecutive interpreting group didn't enhance repeating skill. They also showed that consecutive interpreting could positively affect listening comprehension. Repeating had a weaker correlation with written test scores than consecutive interpreting, both pre- and post-treatment.
These results may indicate that shadowing and repeating have cognitive differences in language processing. Consecutive interpreting may be an effective way to improve listening comprehension for Japanese learners of English.