From the Head of Research and Statistics for the Archbishops' Council, and the Senior Strategy Officer for the Church Commissioners

Sir, - We write in response to "Cleric says report on church growth belies the research" (News, 17 April), which reports on the Revd Dr Mark Hart's critique of the From Anecdote to Evidence summary report on the findings of the research programme. Dr Hart's critique was a selective critique of a document designed to provide a non-technical introduction to the research findings for a wide audience.

The report From Anecdote to Evidence makes clear that "there is no single recipe for growth; there are no simple solutions to decline." In presenting factors associated with growth, it also states: "It is important to note that association by itself does not prove or disprove anything," and "therefore a study can only establish that there is association, not proof of why there is an association." "Given the discovery of an association the next step may be to do further research to test whether, why and how these factors inter-relate." It is simply not correct, therefore, to suggest that the summary report failed to include any caveats.

It is also important to acknowledge that those who carried out and produced the research were able to comment on a number of drafts of the summary report, and agreed the final version. Further, the researchers presented their findings at a conference that took place in London in January 2014, since when Professor Voas's presentation has been available online (www.churchgrowthresearch.org.uk/UserFiles/File//Presentations/CGRP_Voas.pdf).

Dr Hart notes that the factors associated with growth account for only a small proportion of the difference between growing and declining churches (up to 25 per cent). From Anecdote to Evidence explicitly recognised this. Indeed, a quotation from one of the re-searchers making this point was on the back cover of the report.

The associations found in the report have given helpful pointers to where further research may be fruitful, with further research to explore these associations in more depth already under way.

In the mean time, the research provides insights to help guide reflection at all levels of the Church, and actions based on the best available evidence base. The key factors associated with growth were drawn from the self-reported growth by clergy as well as growth figures based on annual-returns data and qualitative interviews with clergy of growing churches.

Dr Hart highlights factors where findings were drawn from the self-reported data, or where the strength of correlation for self-reported data is higher than that found in the annual-returns data - though the direction of correlation is the same - and dismisses them. In doing so, he neglects that self-reported data (covering the period 2008-13) will be more up to date than annual-reports data (2001-11).

Clergy have access to their service registers, and will understand growth in their own context, which is a different indicator to changes in average attendance. The fact that the correlation between self-reported and annual-returns data is low should not be used to dismiss survey findings based on a more recent time period and a different indic-ator. Indeed, Professor Voas highlighted findings based on the self-reported data in his conference presentation.

When presenting the findings to dioceses, both of the important caveats that need to be considered when interpreting the research and the need for further research have been emphasised. The fact remains, however, that the Church Growth Research programme was an important step forward in developing the evidence base relating to numerical growth.

The idea that From Anecdote to Evidence forms the complete evidence basis for decision-making among senior leaders is unfounded. The Archbishops' Council regularly receives updates on demographic, financial, and attendance data. Reform and Renewal builds upon years of evidence-gathering and listening to dioceses, of which the church-growth research programme is one important part.

Bev Botting, Kevin Norris

Church House, Great Smith Street, London SW1P 3AZ