PMC:7795888 / 21334-21427 JSONTXT

{"project":"LitCovid-sentences","denotations":[{"id":"T129","span":{"begin":0,"end":93},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"We understand that the choice of an online survey is not free from methodological risks [40]."}