Clarification from the National Joint Registry

The dataset for this analysis was released on 15th August 2011 by the National Joint Registry (NJR) to Smith & Nephew. The NJR was not aware that the company would pass the data on to the paper’s authors for an analysis of mortality. The information on mortality in the dataset we provided was incomplete, with no times to death given for patients who underwent revision procedures.

We wish to emphasise that the dataset released by the NJR was not linked to hospital episode statistics or patient episode data for Wales. No data were included that would allow linkage to either set of episode data from another source. The NJR is not authorised to release linked data to a third party.