Churches in the UK could be subjected to commercial-style scrutiny in the same way as shops and restaurants under plans to introduce a "mystery worshipper" scheme, it was disclosed yesterday.

The charity Christian Research said it was working on developing a "mystery worshipper" service for churches of all denominations in the UK by May next year.

The plans follow a successful pilot scheme in Telford, Shropshire, where "mystery worshippers" visited 13 churches in the area.

Benita Hewitt, executive director of Christian Research, said the churches were given scores for a range of qualities from exterior appearance to their atmosphere, warmth of welcome and whether they were comfortable.

She said the mystery worshippers had been non-churchgoers who normally worked as mystery shoppers in the commercial world, visiting shops, restaurants, football clubs and hairdressers to assess their services.

The Telford scheme involved a range of denominations and styles of service from High Anglican, she said, to a service involving a "lot of people lying on the floor and being healed."

The results had been "amazingly positive", she said, and more mystery worshippers were due to be dispatched to churches in the wider West Midlands area on January 13.

Mrs Hewitt, whose background is in commercial research, said it was essential that the churches gained an insight into how they were viewed from the "outside in" by non-churchgoers.

She said: "We have had some of our mystery worshippers saying that they were really amazed by what they found - by the atmosphere and the welcome before the service, when they went in and after the service and the fellowship.

Stephen Goddard, co-editor of the Christian website Ship of Fools, and founder of the concept of Mystery Worshipper, said they were working with Christian Research on the initiative.