Does ‘Scientists believe…’ imply ‘All scientists believe...’? Individual differences in the interpretation of generic news headlines

Media headlines reporting scientific research frequently include generic phrases such as “Scientists believe x” or “Experts think y”. These phrases capture attention and succinctly communicate science to the public. However, by generically attributing beliefs to ‘Scientists’, ‘Experts’ or ‘Researchers’ the degree of scientific consensus must be inferred by the reader or listener (do all scientists believe x, most scientists, or just a few?). Our data revealed that decontextualized generic phrases such as “Scientists say…” imply consensus among a majority of relevant experts (53.8% in Study 1 and 60.7-61.8% in Study 2). There was little variation in the degree of consensus implied by different generic phrases, but wide variation between different participants. These ratings of decontextualized phrases will inevitably be labile and prone to change with the addition of context, but under controlled conditions people interpret generic consensus statements in very different ways. We tested the novel hypothesis that individual differences in consensus estimates occur because generic phrases encourage an intuitive overgeneralization (e.g., Scientists believe = All scientists believe) that some people revise downwards on reflection (e.g., Scientists believe = Some scientists believe). Two pre-registered studies failed to support this hypothesis. There was no significant relationship between reflective thinking and consensus estimates (Study 1) and enforced reflection did not cause estimates to be revised downwards (Study 2). Those reporting scientific research should be aware that generically attributing beliefs to ‘Scientists’ or ‘Researchers’ is ambiguous and inappropriate when there is no clear consensus among relevant experts.