Differences in case-mix can influence the comparison of standardised mortality ratios even with optimal risk adjustment: An analysis of data from paediatric intensive care

BMJ Quality and Safety

Volumn 23, Issue 9, 2014, Pages 782-788

  Manktelow, Bradley N ^a   Evans, T Alun ^a   Draper, ElizabethS ^a  

^a UNIVERSITY OF LEICESTER   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

ARTICLE; CASE MIX; DATA ANALYSIS; HEALTH CARE PERSONNEL; HEALTH CARE PRACTICE; HUMAN; INTENSIVE CARE; INTENSIVE CARE UNIT; IRELAND; MORTALITY; OUTCOME ASSESSMENT; RISK ASSESSMENT; STANDARDIZED MORTALITY RATIO; UNITED KINGDOM; CHILD; COMPARATIVE STUDY; DIAGNOSIS RELATED GROUP; HEALTH CARE QUALITY; HOSPITAL MORTALITY; PROCEDURES; STANDARDS; STATISTICAL ANALYSIS; STATISTICAL MODEL; STATISTICS AND NUMERICAL DATA;

CHILD; DATA INTERPRETATION, STATISTICAL; DIAGNOSIS-RELATED GROUPS; HOSPITAL MORTALITY; HUMANS; INTENSIVE CARE UNITS, PEDIATRIC; MODELS, STATISTICAL; QUALITY ASSURANCE, HEALTH CARE; RISK ADJUSTMENT;

EID: 84906654468     PISSN: 20445415     EISSN: None     Source Type: Journal    
DOI: 10.1136/bmjqs-2013-002608     Document Type: Article

References (35)

1. Keogh B. Review into the quality of care and treatment provided by 14 hospital trusts in England: overview report. London: NHS, 2013.
2. Francis R. Report of the Mid Staffordshire NHS Foundation Trust Public Inquiry. London: The Stationery Office, 2013.
3. Dyer C. Suspension of paediatric heart surgery at Leeds provokes controversy. BMJ 2013;346:f2098.
4. NHS Choices. Your choices: consultant choice. http://www.nhs.uk/ choiceintheNHS/Yourchoices/consultant-choice/Pages/consultant-data.aspx (accessed 28 Jun 2013).
5. Fung CH, Lim Y-W, Mattke S, et al. Systematic review: the evidence that publishing patient care performance data improves quality of care. Ann Intern Med 2008;148:111-23. (Pubitemid 351651554)
6. Doran T, Fullwood C, Gravelle H, et al. Pay-for-performance programs in family practices in the United Kingdom. N Engl J Med 2006;355:375-84. (Pubitemid 44127540)
7. Saint-Lary O, Plu I, Naiditch M. Ethical issues raised by the introduction of payment for performance in France. J Med Ethics 2012;38:485-91.
8. Signorini DF, Weir NU. Any variability in outcome comparisons adjusted for case mix must be accounted for. BMJ 1999;318:128. (Pubitemid 29188946)
9. Keiding N. Standardized mortality ratio and statistical analysis: historical perspective. Biometrics 1985;41:1096.
10. Le Gall JR. The use of severity scores in the intensive care unit. Intensive Care Med 2005;31:1618-23.
11. Mohammed MA, Manktelow BN, Hofer TP. Comparison of four methods for deriving hospital standardised mortality ratios from a single hierarchical logistic regression model. Stat Methods Med Res. Published Online First: 6 November 2012. doi: 10.1177/0962280212465165.
12. Krumholz HM, Wang Y, Mattera JA, et al. An administrative claims model suitable for profiling hospital performance based on 30-day mortality rates among patients with an acute myocardial infarction. Circulation 2006;113:1683-92.
13. Dr Foster Intelligence. Understanding HSMRs. A toolkit on hospital standardised mortality ratios. London: Dr Foster Intelligence, 2011.
14. Campbell MJ, Jacques RM, Fotheringham J, et al. Developing a summary hospital mortality index: retrospective analysis in English hospitals over five years. BMJ 2012;344:e1001.
15. Silcock H. The comparison of occupational mortality rates. Popul Stud 1959;13:183-92.
16. Julious SA, Nicholl J, George S. Why do we continue to use standardized mortality ratios for small area comparisons? J Public Health 2001;23:40-6. (Pubitemid 32246300)
17. Hollis S, Yates DW, Woodford M, et al. Standardized comparison of performance indicators in trauma: a new approach to case-mix variation. J Trauma 1995;38:763-6.
18. Nicholl J, Jacques RM, Campbell MJ. Direct risk standardisation: a new method for comparing casemix adjusted event rates using complex models. BMC Med Res Methodol 2013;13:133.
19. Julious SA, George S. Are hospital league tables calculated correctly? Public Health 2007;121:902-4. (Pubitemid 350138987)
20. Yule GU. On some points relating to vital statistics, more especially statistics of occupational mortality. J R Stat Soc 1934;97:1-84.
21. Simpson EH. The interpretation of interaction in contingency tables. J R Stat Soc B Methodol 1951;13:238-41.
22. Court BV, Cheng KK. Pros and cons of standardised mortality ratios. Lancet 1995;346:1432.
23. Aylin P, Bottle A. Are hospital league tables calculated correctly? A commentary. Public Health 2007;121:905-6. (Pubitemid 350138986)
24. Glance LG, Osler T, Shinozaki T. Effect of varying the case mix on the standardized mortality ratio and W statistic-a simulation study. Chest 2000;117:1112-17. (Pubitemid 30228373)
25. Pouw ME, Peelen LM, Lingsma HF, et al. Hospital Standardized Mortality Ratio: consequences of adjusting hospital mortality with indirect standardization. PLoS ONE 2013;8:e59160.
26. Evans TA, Seaton SE, Manktelow BN. Quantifying the potential bias when directly comparing Standardised Mortality Ratios for in-unit neonatal mortality. PLoS ONE 2013;8:e61237.
27. Marlow N, Gill AB. Establishing neonatal networks: the reality. Arch Dis Child Fetal Neonatal Ed 2007;92:F137-42. (Pubitemid 46423831)
28. Paediatric Intensive Care Audit Network. 2012. http://www.picanet.org.uk/ (accessed 25 Jul 2013).
29. Slater A, Shann F, Pearson G; for the PIM Study Group. PIM2: a revised version of the Paediatric Index of Mortality. Intensive Care Med 2003;29:278-85. (Pubitemid 36384419)
30. Lee WC. Properties of the geometrically averaged ratio, an alternative standardized measure. Epidemiology 1999;10:456-9.
31. Lee WC. Standardization using the harmonically weighted ratios: internal and external comparisons. Stat Med 2002;21:247-61.
32. Rosenbaum PR, Rubin DB. Reducing bias in observational studies using subclassification on the propensity score. J Am Stat Assoc 1984;79:516-24.
33. Shahian DM, Normand S-LT. Comparison of "risk adjusted" hospital outcomes. Circulation 2008;117:1955-63. (Pubitemid 351543471)
34. Boyd O, Grounds M. Can standardized mortality ratio be used to compare quality of intensive-care unit performance. Crit Care Med 1994;22:1706-8.
35. Hawkes N. Head of healthcare watchdog resigns after series of damming reports. BMJ 2012;344:e1396.