International Migration 48/5 2010
There will always be some limitations and biases in empirical research in the trafficking field. However, as long as we acknowledge these limitations and make them explicit in our research, sound empirical research that enhances our knowledge in this field is possible. The best potential for good quality research lies in small-scale, thematically focused empirical studies, while attempts to describe worldwide trafficking across regions and arenas is less likely to be successful.
Read more here