Trinity Mirror North West & North Wales has been cleared of any wrongdoing in a statement on readership figures for some of its weekly newspapers.

Claims made in a wraparound advert for The Formby Times, Southport Visiter, Midweek Visiter and Ormskirk Advertiser Series were challenged by Champion Newspapers, which also publishes newspapers in the area.

The advert said that The Formby Times had almost doubled its readership over the last three years and in the same period the Visiter series had increased its readership by 17,000 and the Ormskirk Advertiser had gained 12,700 more readers.

But Champion Newspapers disputed this, saying that the circulation figures of the Formby Times, Southport Visiter and Ormskirk Advertiser had fallen in the last three years.

It also challenged a further claim, that 93 per cent more people would turn to the Trinity Mirror titles “rather than the local competitor newspaper group when looking for bargains in the classified ad section”.

The Advertising Standards Authority investigated the advert under the rules of the advertising code covering substantiation and truthfulness. Claims comparing Trinity titles with competitors were also examined under a further clause of other comparisons.

Trinity Mirror said the claims were based on the results of a 2005 survey carried out on their behalf by GfK NOP, an independent research agency, which followed strict guidelines set by JICREG, and the relevant parts of the results were given to the ASA.

Trinity Mirror argued that there was no linear relationship between circulation and readership and that it was possible to experience an increase in readership at the same time as a reduction in circulation and vice versa.

It said the 2005 survey had found that there was a significant increase in the readers per copy on a number of its titles and said this was largely a result of an increase in ‘pass-on readership’ – people reading a title they had not bought themselves – which had given them large increases in title readership not in line with their circulation figures.

Trinity Mirror sent the results to the ASA from the 2005 and 2002 surveys, for the Formby Times, which stated that the paper had an average issue readership of 22,500, rounded to 23,000 in the ad, across the Merseyside 10 per cent area in 2005; compared to the 2002 figure of 12,000 – and so it was correct to state it had almost doubled.

It said it had made a mistake with the wording of the ad: the text “Base: All adults in the Formby Times 10% area” was incorrect and should have stated “Base: all adults in Merseyside 10% area”.

The survey data for the Southport Visiter and Ormskirk Advertiser also backed up the advert’s claims, but Trinity said a mistake had also been made with the base for the Visiter claim, which should have stated “Merseyside 10% area” and not “Southport Visiter 10% area”, and the ad had mistakenly quoted the 2005 figure from the Merseyside 10% area (49,000) and not the figure from the comparable Ormskirk Advertiser Series 10% area (47,900).

The ASA said it was concerned that the publisher had stated the incorrect base for several of the claims and reminded it to ensure that future similar ads stated the correct information.

But it said that those mistakes were unlikely to materially mislead readers about the readership of the papers. It concluded that Trinity Mirror had substantiated the claims and that the ad was unlikely to mislead.