Subgroup analysis: application to individual patient decisions

Simes, R John; Gebski, Val J; Keech, Anthony C

doi:10.5694/j.1326-5377.2004.tb06027.x

Topics

Statistics, epidemiology and research design

Clinical trials provide evidence of effectiveness of treatments as an average for a group of patients, yet, in clinical medicine, we usually wish to apply these results to individuals. Can we simply apply the overall trial result for each patient, or can the result be tailored to individual patients in some way?

NHMRC Clinical Trials Centre, Camperdown, NSW.

Correspondence:

Competing interests:

None identified.

1. Cook DI, Gebski VJ, Keech AC. Subgroup analysis in clinical trials. Med J Aust 2004; 180: 289-291. <eMJA full text>
2. Moher D, Schulz KF, Altman DG. The CONSORT statement: revised recommendations for improving the quality of reports of parallel-group randomised trials. Lancet 2001; 357: 1191-1194.
3. Moye LA. Multiple analyses in clinical trials. Fundamentals for investigators. New York: Springer, 2000: 287-289.
4. Altman DG, Matthews JNS. Statistics notes: interaction 1: heterogeneity of effects. BMJ 1996; 313: 486.
5. Matthews JNS, Altman DG. Statistics notes: interaction 2: compare effect sizes not P values. BMJ 1996; 313: 808.
6. Altman DG, Bland JM. Interaction revisited: the difference between two estimates. BMJ 2003; 326: 219.
7. Yusuf S, Wittes J, Probstfield J, Tyroler HA. Analysis and interpretation of subgroups of patients in randomized clinical trials. JAMA 1991; 266: 93-98.
8. Nuovo J, Melnikow J, Chang D. Reporting number needed to treat and absolute risk reduction in randomized controlled trials. JAMA 2002; 287: 2813-2814.
9. ISIS-2 (Second International Study of Infarct Survival) Collaborative Group. Randomised trial of intravenous streptokinase, oral aspirin, both, or neither among 17 187 cases of suspected acute myocardial infarction: ISIS-2. Lancet 1988; ii: 349-360.
10. FTT Collaboration. Indications for fibrinolytic therapy in suspected acute myocardial infarction: collaborative overview of early mortality and major morbidity results from all randomised trials of more than 1000 patients. Lancet 1994; 343: 311-322.
11. White H. Hirulog and Early Reperfusion or Occlusion (HERO) 2 Trial Investigators. Thrombin-specific anticoagulation with bivalirudin versus heparin in patients receiving fibrinolytic therapy for acute myocardial infarction: the HERO-2 randomised trial. Lancet 2001; 358: 1855-1863.
12. PCAT Collaboration. Primary coronary angioplasty compared with intravenous thrombolytic therapy for acute myocardial infarction: six-month follow-up and analysis of individual patient data from randomized trials. Am Heart J 2003; 145: 47-57.
13. Hunt D, Young P, Simes J, et al, for the LIPID investigators. Benefits of pravastatin on cardiovascular events and mortality in older patients with coronary heart disease are equal to or exceed those seen in younger patients. Ann Intern Med 2001; 134: 931-940.
14. Hague W, Forder P, Simes J, et al, on behalf of the LIPID Investigators. Effect of pravastatin on cardiovascular events and mortality in 1516 women with coronary heart disease: results from the LIPID study. Am Heart J 2003; 145: 643-651.
15. Heart Protection Study Collaborative Group. MRC/BHF Heart Protection Study of cholesterol lowering with simvastatin in 4963 people with diabetes: a randomised placebo-controlled trial. Lancet 2003; 361: 2005-2016.

Online responses are no longer available. Please refer to our instructions for authors page for more information.