Abstract copyright UK Data Service and data collection copyright owner.
The aim of the study was to estimate the number of cases of gastro-enteritis, or infectious intestinal diseases (IID) occurring in the population of England, and to find out how many people with IID consulted their GPs and how these numbers compared with the numbers in national surveillance. Because it is impossible to separate out with any precision those cases of IID which result from food poisoning and those resulting from other causes, the study necessarily addressed all cases of IID and not merely the cases caused by eating contaminated food. Therefore, also included in the study were cases infected with pathogens known to be spread predominantly from person to person, and those infected with pathogens usually held responsible for food poisoning, as well as those cases who, although clinically suffering from IID, had no pathogen found in their stools. The study attempted to estimate the accuracy of laboratory reporting to the Public Health Laboratory Service (PHLS) and Communicable Disease Surveillance Centre (CDSC); it did not attempt to determine the accuracy of national food poisoning statistics, which depend upon statutory notifications by doctors on the basis of clinical suspicion. The specific objectives of the study were: to estimate the number and aetiology of cases of IID in the population, presenting to GPs, and having stool specimens sent routinely for laboratory examination; to compare these numbers and the aetiologies with those recorded by the national laboratory surveillance system; to estimate the prevalence of asymptomatic infection with agents associated with IID; to document differences between cases of IID (in the population and presenting to GPs) and similar but well people (controls); to estimate the socio-economic burden of IID and its distribution, determine how much respondents would be willing to pay for safer food and who they held responsible for food safety. The IID study also included a long-term follow-up component. The objectives of the long-term study were to identify the risks and incidence of the long-term sequellae (LTS) of IID, both overall and if possible for the major organisms, in particular campylobacter, shigella, yersinia, rotavirus, SRSV and those with no 'target' organisms. The long-term follow-up component is not currently available from the UK Data Archive (UKDA), as the principal investigators are still completing their analysis of the data.
Main Topics:
The IID study contains five groups of databases each associated with a different aspect of the study: 1. Study administration forms - each data file contains information from a different study administration form. 2. Data collection management databases - files compiled from databases created to monitor data collection. 3. Questionnaire data - databases containing data from different study questionnaires. From these, new data files have been developed which contain the questionnaire data, additional variables and some recoding of variables to prepare the data for statistical analysis. 4. Data on microbiology - databases received from investigating laboratories. From these, new data files have been created by merging the separate databases to prepare the data for statistical analysis. Some files from the microbiology databases are not available from the UK Data Archive. 5. Information on general practices and age/sex distribution of general practice registered population. Standard Measures OPCS Standard Occupational Classification, vols 1-3, OPCS: used to obtain social class classification based on occupation; Read codes (Computer Aided Medical Systems Ltd., 1992); Jarman Deprivation Score.
Multi-stage stratified random sample
Face-to-face interview
Clinical measurements
