PMC:7796344 / 23662-23901 JSONTXT

{"project":"LitCovid-sentences","denotations":[{"id":"T164","span":{"begin":0,"end":239},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"There may also be recruitment bias from the researchers at the airport in whom they approach and participation bias in those who decided to take part in this study and the responses (the number of refusals to participate was not recorded)."}