You asked
I wonder who or what checks to see if the survey letters you have sent out have been completed.
I completed such a survey earlier this week, and have just received another letter telling me I have until 2 March to complete the online survey.
The time, effort and money spent on this second missive is wasted, and makes me wonder how much wastage there is in The Office of National Statstics.
We said
Thank you for your question regarding the issue of duplicate letters on the ONS survey you were asked to participate in. The respondent communications strategy for this online survey has been developed based on extensive research which has provided evidence that multiple contacts by letter to households helps ONS to obtain responses from as many households as possible. The more households that take part, the higher the quality of the statistics we can produce.
Our research shows that sending a prenotification letter (Letter 1) prepares people to take part in the survey and they act sooner when they receive the invitation letter (Letter 2), allowing for timely data collection. Two reminder letters (Letters 3 and 4) also provide a boost to response allowing those who have not yet had the chance to complete another opportunity to do so. Our aim is to only send reminders to households that haven't taken part in the survey at the time that those letters are printed, so not all households will receive all 4 letters.
Unfortunately there are occasions however when households are sent a reminder letter when they have already declined to take part by calling our Survey Enquiry Line or when they have completed the survey but the reminder letter crosses over. We are developing our systems to try to ensure that this doesn't happen in the future. It can also be the case that delays with the Royal Mail delivery service means that letters arrive later than intended. This is very unfortunate and not what we would want to happen.
The data from this survey allows ONS to produce reliable and accurate statistics for use by the Government, including data relating to the COVID-19 pandemic. Some households that take part in this survey are also invited to take part in further studies related to the pandemic, the COVID-19 Infection Study, relating to infection rates and antibodies, or the Opinions Survey which has measured the impact of COVID-19 on people, households and communities in Great Britain. The data we collect from households invited to take part in the survey has been of great importance to producing accurate and timely statistics relating to the COVID-19 pandemic across England, Wales, Scotland and Northern Ireland, which has in turn helped to inform Government decision making.
We trust that this adequately explains the value of the data that ONS is currently collecting and our reasons for sending more than just one letter to encourage participation in our surveys. We are committed to delivering value for money and we continuously monitor our response survey response rates and review our engagement strategy to make sure it is appropriate. We are also developing our systems so that the number of letters we send out unnecessarily declines.
Please also see the following previously answered FOI, which provides details of the costs you have requested: Cost of duplicated letters sent to households