1. Is the review comprehensive?
2. Are all cited references relevant to the problem under investigation?
3. Are most of the sources primary, i.e., are there only a few or no secondary sources?
4. Have the references been critically analyzed and the results of various studies compared and contrasted, i.e., is the review more than a series of abstracts or annotations?
5. Does the review conclude with a brief summary of the literature and its implications for the problem investigated?
6. Do the implications discussed form an empirical or theoretical rationale for the hypotheses which follow?