Sir

I was excited when Nature launched its trial for open peer review last year, but disappointed by the outcome (see http://blogs.nature.com/nature/peerreview/trial). I have also been tracking the progress of another open review journal, Biology Direct (http://www.biology-direct.com; see article in Nature's peer-review debate at http://www.nature.com/nature/peerreview/debate/nature05005.html). Even after a high-profile launch with guaranteed indexing by PubMed, this journal has published only 52 articles and received only two comments over 16 months.

In contrast to Biology Direct, another journal that offers open commenting, PLoS One (http://www.plosone.org), has published 1,189 articles in its first six months. But has PLoS One achieved its stated goal of post-publication open comments? I find that even the 'most annotated' category of articles usually receives just a few comments. The journal has recently replaced its 'most annotated' with a 'recently annotated' category. A check of all 'recently annotated' articles demonstrates that their commenting rates are low (zero or just a few), even for articles that are likely to have broad appeal and/or are in 'hot' research areas.

Why is there a general lack of interest among the scientific community in open commenting on submitted or published papers? I believe there are two main reasons. First, participation does not earn any tangible credit or benefit for the reviewers and commentators. Second, publicly critical comments are a risk for those who make them.