Signing consent to participate in the research Volunteers sign in signature only, or in succinct writing only. or both the signature and the embossed by nrctadmin 21 สิงหาคม 2022 written by nrctadmin 21 สิงหาคม 2022 Signing consent to participate in the research Volunteers should sign their signatures. and write 0 comment 0 FacebookTwitterPinterestEmail nrctadmin previous post The researcher has completed the research. While waiting for research to be published, the EC certificate (COA), usually valid for 1 year, has expired. Does the researcher have to request an ethics certificate? Leave a Comment Cancel Reply Save my name, email, and website in this browser for the next time I comment.