An error has been found in the estimates on Nomis for the Annual Population Survey variable "% with NVQ3+ aged 16-64". The error resulted in counts for this variable being over stated. The error was fixed on 11 October 2016. Data downloaded prior to this date for this variable would have been incorrect. No other APS variables were affected.


Qualifications data for the Annual Population Survey is classified to different levels depending on the highest level of qualification reported by the interviewee. These levels are then reflected on Nomis as estimates of the number of people with:

  • no qualifications,
  • other qualifications,
  • NVQ1,
  • NVQ2,
  • Trade Apprenticeships,
  • NVQ3, and
  • NVQ4+.

In addition to estimates of the numbers at each level, cumulative numbers are also produced based on those qualified to:

  • NVQ1+,
  • NVQ2+, and
  • NVQ3+.

Although for most qualifications it is clear which cumulative level they should be classified to, Trade Apprenticeships are less easily allocated since there is significant variation in the apprenticeships available. Following long standing guidance, the convention is that half of any Trade Apprenticeships should be included in estimates of NVQ3+, with the other half additionally included when you are looking at estimates of NVQ2+.

Historically Nomis has followed this convention.

Recently it was discovered that at some point the categories on Nomis had unintentionally stopped following this guidance, with all the Trade Apprenticeships being included in the NVQ3+ estimates. It is not clear when this error first started occurring. The error has subsequently been corrected.

The consequence is that any data downloaded while the error was in place will have overstated the number of people with NVQ3+ qualifications. This correction may lead to differences between data subsequently downloaded for this variable and earlier downloads of this information.