We used content analysis, which is

We used content analysis, which is a method that converts qualitative material into quantitative material that subsequently can be analyzed subject to the limitations of nominal level measurement (cf. Aguinis, Henle, & Ostroff, 2001; G. Shapiro & Markoff, 1997). More specifically, our data collection procedure consisted of manually coding every article published in every issue between January 1963 and May 2007 in JAP and PPsych on the basis of its content. In total, we coded 5,780 articles in the two journals (n