The bacterial infection Clostridium difficile is most effectively diagnosed through a method called cytotoxin assay, a new study has found.

British researchers looked for the most accurate diagnosis methods involved in fatal C. diff cases, and published their methodology in The Lancet Infectious Diseases yesterday. The investigators tested via both cytotoxigenic cultures and through cytotoxin assay for more than 12,000 people. People who tested positive through cytotoxin assay, which detects C. diff toxin in fecal samples, were almost twice as likely to die within 30 days.

The finding proves that the detection method is the most effective in diagnosing cases of C. diff, the authors wrote.

This study builds on recent C. diff news, such as whether probiotics are effective in treating the digestive disease and government controls on fecal implants.