Patients could be put off taking part in NHS outcome measurement by overwhelmingly long questionnaires, market researchers fear.

Health service market research specialists are divided on proposals for survey documents up to 15 pages long when patient reported outcome measures are introduced across the service in April.

BUPA Foundation group medical director Andrew Vallance-Owen said: "We think it will be difficult to get a high response rate with a document of that size. I worry it could set back the cause of [patient reporting] if the response rates are low."

The size of the questionnaire is revealed in a Department of Health tender document for running parts of the reporting process.

Under DH proposals in the 2008-09 operating framework, hip and knee replacement patients and those having groin hernia and varicose vein surgeries will complete questionnaires before and three months after the procedures.

Out of touch

CHKS head of market intelligence Paul Robinson said: "I can see no reason for the questionnaires being that long." The proposals reflected "a researchers' view of doing things", he said.

CHKS and BUPA have worked with patient reported outcomes measurement privately for several years.

The plans are based on a 2,400-patient London School of Hygiene and Tropical Medicine pilot. Professor of health services research Nick Black said the system had been proved effective.

Around 81-90 per cent of eligible patients opted to complete a pre-operative questionnaire and of those there was a 75-91 per cent response rate to the post-operative survey. Response rates of 80 per cent and above are considered acceptable.

Technical issues

He said: "The questionnaire is one we developed for the DH and it works. These are technical issues - they are a complete distraction."

Professor Black said it was right that the system was based in research, but agreed practical issues such as the length were important.

The London School of Hygiene and Tropical Medicine with the Royal College of Surgeons, CHKS and BUPA-owned Outcome Technologies have shown interest in the tender, which envisages pre-operative surveys of 10-15 pages and post-operative ones of up to 11 pages, each expected to contain around 30 questions.

A DH spokeswoman said patients will not be expected to complete a set of questions "that stretch over 10-15 pages. This includes covers, patient information and consent forms". She said the DH was confident of good response rates.

HSJ's Performance Management conference is on 11 November.