People are more likely to be admitted to hospital with food poisoning after attending a private dinner party or barbecue than after eating at a restaurant, a study has revealed.

The Public Health Laboratory Service, which surveyed all outbreaks of infectious intestinal disease in private households in England and Wales from 1992 to 1999, found 4,602 people were affected, of whom 205 were admitted to hospital.

The chance of a dinner guest being treated in hospital was higher than that for people going out to restaurants or hotels or eating in canteens. The most common cause of food poisoning was cross-contamination when uncooked food such as raw meat came into contact with ready-to-eat food – likeliest in a crowded fridge. Food left in a warm room also provided ideal conditions for bacteria to thrive.

Iain Gillespie, an author of the study published in the British Medical Journal, said: "People are catering for larger numbers than they used to so they are more likely to make mistakes with food safety."