A new National Board study authored by Leslie Vandevoort, Audrey Amrein-Beardsley, and David Berliner was released last week, claiming that Board-certified teachers produce higher student achievement gains than non-Board certified teachers. Unlike Dan Goldhaber's study last spring that found Board-certified teachers to be more effective, studies like this one do little to appease National Board critics. This study is unlikely to convince anyone of anything except that ed research continues to suffer from embarrassingly low standards.
Where did this study go wrong? Apparently on day one, when the research team sent a letter out to the eighty Board-certified teachers residing in Arizona. These teachers were asked if they would participate in a study of the effectiveness of Board-certified teachers, which would require that they share their student achievement data. Thirty-five teachers signed up; forty-five didn't. Onward went the study. Principles such as self-selection bias and random assignment didn't appear to bother the researchers, who produced a 116 page study that drips with the authors' resentment over the necessity of documenting the effectiveness of Board-certified teachers when that's not what doctors have to do.
Nevertheless, the study passed muster with Gene Glass's Education Policy Analysis Archives, earned itself some play in Ed Week, and will no doubt be a frequent cite among the "ever increasing body of new and developing research studies" linking Board certification with student achievement. As Andy Rotherham of Eduwonk aptly pointed out, stick with Goldhaber.