Section B – Additional recommendation

Finding

We support ONS’s recent decision to extend the transformation timetable and continue with the parallel run until December 2023 allowing extra time for ONS to sufficiently understand and assure the quality of TLFS data before making the decision to decommission the existing survey. Given the importance of the LFS and the public value that the statistics from it provide, it is really important that statistics from the transformed survey meet high statistical standards so that users have confidence in the accuracy and reliability of data collected in the new survey and in any decisions being made by ONS about methods. We are pleased to hear that ONS plans to share TLFS data and early insights with both expert and less expert users – their questions, challenge and advice will help refine and assure the quality of data from the TLFS as part of the parallel run. Engagement will also help to manage expectations and give users the opportunity to familiarise themselves with the new data.

At the same time, the extension of the timetable raises questions about the sustainability of the current LFS. Continued declining response rates mean that more reliance is placed on statistical methods to estimate the missing responses to ensure the data are an accurate representation of what the survey is trying to measure. Our recent engagement with users highlighted concerns around the current weighting methods used in the LFS.

LFS estimates continue to use weights based on projected growth rates from HM Revenue and Customs (HMRC) Real Time Information (RTI) data for EU and non-EU populations based on 2021 patterns. By not taking into account any changes in the population (through birth/death rates and migration), there is a risk that estimates become less representative of the true values, which in turn can affect user confidence. The LFS team told us that it considers the estimates of rates to be robust. These questions about weights, though, enhance the importance of ONS clearly articulating the uncertainties in the estimates.

The LFS team told us that work is underway to assess the impact of reweighting the LFS using most recent 2022 population projections and that it is regularly liaising with key users on their concerns.

Recommendation 7 – Quality