Referee 1's review:

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N.B. These are the comments made by the referee when reviewing an earlier version of this paper. Prior to publication, the manuscript has been revised in light of these comments and to address other editorial requirements.
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PLoS ONE review:

This paper by Bate et al addresses an important issue of anti-malaria drug, the quality of anti-malaria drug, which has linked to the drug resistance and could affect our ability to control this deadly disease.

One hundred and ninety-five drug packs were collected from six Africa countries and drug quality was tested by commonly used approach, thin-layer chromatography (TLC) and dissolution test. The results showed the high persistence of substandard drug (35%) and clinically inappropriate artemisinin monotherapies in these countries. The paper is presented in an intelligible fashion and well written in English. The findings are important and of sufficient significance for publication in PLoS ONE.

The following review article could be cited as a background literature, especially for non-malariologist.

Amin AA, Kokwaro GO. Antimalarial drug quality in Africa.
J Clin Pharm Ther. 2007 Oct;32(5):429-40. Review.