Lucent

DOI check: 10.1016/S0140-6736(20)31180-6

Crossref records a retraction notice for this DOI (field: update-to).

flagged

Crossref records a retraction-related field for this DOI (update-to, update-to, update-to, update-to, updated-by, updated-by).

RETRACTED: Hydroxychloroquine or chloroquine with or without a macrolide for treatment of COVID-19: a multinational registry analysis

Source: Crossref works API. Checked 2026-07-08 08:34 UTC.

What this checks, exactly

Lucent called Crossref's public works API for this DOI and read three fields: update-to, updated-by, and relation entries typed is-retracted-by or is-retraction-of. If any of those name a retraction, this page says so and names the field. If none do, it says the metadata carries no retraction-related field as of the check date, never that the paper is "safe" or "clear" of other problems: this checks disclosed integrity signals, not whether a paper's conclusions are correct. If Crossref has no record for the DOI, that is reported as unknown, never as a pass.

Run another DOI through the live checker, or read what a paper retraction is.

Lucent runs this same check on every paper it publishes, every two days.

Brand-new papers in plain language, each screened for retractions and a live DOI before you ever see them. Three free every issue.

What is a paper retraction?  ·  How to tell if a study is trustworthy  ·  Latest issue  ·  Privacy