Relationship between preventable hospital deaths and other measures of safety: an exploratory study.
OBJECTIVE
To explore associations between the proportion of hospital deaths that are preventable and other measures of safety.


METHODS
Retrospective case record review to provide estimates of preventable death proportions. Simple monotonic correlations using Spearman's rank correlation coefficient to establish the relationship with eight other measures of patient safety.


METHODS
Ten English acute hospital trusts.


METHODS
One thousand patients who died during 2009.


RESULTS
The proportion of preventable deaths varied between hospitals (3-8%) but was not statistically significant (P = 0.94). Only one of the eight measures of safety (Methicillin-resistant Staphylococcus aureus bacteraemia rate) was clinically and statistically significantly associated with preventable death proportion (r = 0.73; P < 0.02). There were no significant associations with the other measures including hospital standardized mortality ratios (r = -0.01). There was a suggestion that preventable deaths may be more strongly associated with some other measures of outcome than with process or with structure measures.


CONCLUSIONS
The exploratory nature of this study inevitably limited its power to provide definitive results. The observed relationships between safety measures suggest that a larger more powerful study is needed to establish the inter-relationship of different measures of safety (structure, process and outcome), in particular the widely used standardized mortality ratios.
Department of Health Services Research and Policy, London School of Hygiene and Tropical Medicine, London, UK.
Helen
H
Hogan
NHS England, London, UK.
Frances
F
Healey
Clinical Safety Research Unit, Imperial College, London, UK.
Graham
G
Neale
Institute of Health and Society, University of Newcastle, Newcastle upon Tyne, UK.
Richard
R
Thomson
Department of Experimental Psychology, Oxford University, Oxford.
Charles
C
Vincent
Department of Health Services Research and Policy, London School of Hygiene and Tropical Medicine, London, UK.
Nick
N
Black
D000328:Adult; D004739:England / Q000453:epidemiology; D005260:Female; D006302:Health Services Research; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D008297:Male; D061214:Patient Safety; D019984:Quality Indicators, Health Care; D011787:Quality of Health Care; D012189:Retrospective Studies; D017751:Safety Management / Q000458:organization & administration*; D013222:State Medicine
hospital standardized mortality ratio; patient safety measures; preventable death