@article {Sari434, author = {Ali Baba-Akbari Sari and Trevor A Sheldon and Alison Cracknell and Alastair Turnbull and Yvonne Dobson and Celia Grant and William Gray and Aileen Richardson}, title = {Extent, nature and consequences of adverse events: results of a retrospective casenote review in a large NHS hospital}, volume = {16}, number = {6}, pages = {434--439}, year = {2007}, doi = {10.1136/qshc.2006.021154}, publisher = {BMJ Publishing Group Ltd}, abstract = {Objectives: To estimate the extent, nature and consequences of adverse events in a large National Health Service (NHS) hospital, and to evaluate the reliability of a two-stage casenote review method in identifying adverse events.Design: A two-stage structured retrospective patient casenote review.Setting: A large NHS hospital in England.Population: A random sample of 1006 hospital admissions between January and May 2004: surgery (n = 311), general medicine (n = 251), elderly (n = 184), orthopaedics (n = 131), urology (n = 61) and three other specialties (n = 68).Main outcome measures: Proportion of admissions with adverse events, the proportion of preventable adverse events, and the types and consequences of adverse events.Results: 8.7\% (n = 87) of the 1006 admissions had at least one adverse event (95\% CI 7.0\% to 10.4\%), of which 31\% (n = 27) were preventable. 15\% of adverse events led to impairment or disability which lasted more than 6 months and another 10\% contributed to patient death. Adverse events led to a mean increased length of stay of 8 days (95\% CI 6.5 to 9). The sensitivity of the screening criteria in identifying adverse events was 92\% (95\% CI 87\% to 96\%) and the specificity was 62\% (95\% CI 53\% to 71\%). Inter-rater reliability for determination of adverse events was good (κ = 0.64), but for the assessment of preventability it was only moderate (κ = 0.44).Conclusion: This study confirms that adverse events are common, serious and potentially preventable source of harm to patients in NHS hospitals. The accuracy and reliability of a structured two-stage casenote review in identifying adverse events in the UK was confirmed.}, issn = {1475-3898}, URL = {https://qualitysafety.bmj.com/content/16/6/434}, eprint = {https://qualitysafety.bmj.com/content/16/6/434.full.pdf}, journal = {BMJ Quality \& Safety} }