- choosing a career that is consistent with or matches your Holland interests (RIASEC types) results in higher earnings;
- Job congruence affects earnings almost to the same order of magnitude as additional years of schooling.
On the Career Key website, we have tips on how to tell whether or not a test is "scientifically valid", including a download of a recent National Career Development Association Career Developments magazine article about evaluating and choosing a career test written by Career Key author Dr. Lawrence K. Jones.
Neumann, G., Olitsky, N., Robbins, S. (2009) Job congruence, academic achievement, and earnings. Labour Economics, 16, 503-509.