en.wikipedia.org/wiki/Whitehall_Study

The article's list of Whitehall II waves gives phase 3 as 1991-1993. UCL's official Whitehall II data-collection page instead lists Phase 3 as 1991-1994.

Because this is a specific chronology claim about a named study wave, and the official project page gives a different date range for that same wave, the 1991-1993 range here is inaccurate.

The article states that Whitehall II's first wave was "phase 1 (1984-1985; age 35 to 55)." But UCL's official Whitehall II data-collection page lists Phase 1 as 1985-1988 and shows 10,308 participants in that phase. That matches the standard description of Whitehall II baseline recruitment and contradicts the 1984-1985 date given here.

Because the claim gives a specific date range, and the official project page gives a different specific date range for the same phase, this is a factual error rather than a matter of interpretation.

This sentence gives precise start and end dates for Whitehall II phase 13. UCL's official Phase 13 page states that the thirteenth phase "started in March 2019 and finished in January 2023." That directly contradicts the article's claim that it began in February 2019.

Because the official study page names the exact month and year for the phase start, the February 2019 date here is incorrect.