Article Text

Download PDFPDF

How should clinicians interpret results reflecting the effect of an intervention on composite end points: should I dump this lump?
Free
  1. VICTOR M MONTORI, MD, MSC1,
  2. JASON W BUSSES, DC, MSC2,
  3. GAIETÀ PERMANYER MIRALDA, MD3,
  4. IGNACIO FERREIRA, MD4,
  5. GORDON H GUYATT, MD, MSC5
  1. 1Mayo Clinic College of Medicine
 Rochester, Minnesota, USA
  2. 2McMaster University
 Hamilton, Ontario, Canada
  3. 3Hospital General Vall d’Hebron
 Barcelona, Spain
  4. 4Universitat Autònoma de Barcelona
 Barcelona, Spain
  5. 5McMaster University
 Hamilton, Ontario, Canada

    Statistics from Altmetric.com

    In this issue, Evidence-Based Medicine highlights and comments on a landmark randomised trial, the ACHOIS trial.1 In this trial, Crowther and her colleagues enrolled 1000 pregnant women with mild gestational diabetes who were either informed of their diagnosis and received treatment (including individual dietary advice, instruction on self monitoring of blood glucose concentrations, and insulin therapy as needed) or informed that they did not have gestational diabetes and assigned routine prenatal care unless subsequent findings suggested diabetes.

    The ACHOIS trial was designed to determine the extent to which aggressive treatment of mild gestational diabetes affects outcomes in the mothers (induction of labor and caesarean section) and in the infants (a composite of death, shoulder dystocia, bone fracture, and nerve palsy dubbed “any serious perinatal complications”).

    For the maternal outcomes, 189 of 490 (39%) of mothers in the intervention group and 150 of 510 (29%) in the routine care group required induction of labour; 152 (31%) and 164 (32%) required caesarean delivery. We will examine the implications of these results using numbers needed to treat (NNTs) under the assumption that all women with mild gestational diabetes are at the same risk of adverse outcomes and that their risk approximates that of the average woman enrolled in the ACHOIS trial (women at identifiably higher risk of these outcomes would have smaller NNTs, and vice versa). While the trial evidence suggests no difference in the rate of caesarean sections, it tells us that for every 11 (95% CI 7 to 31) women screened and managed for gestational diabetes, 1 additional woman will require induction of labour. Furthermore, clinicians admitted 357 of 506 (71%) and 321 of 524 (61%) infants in the intervention and routine care groups to the neonatal nursery, respectively. Thus, for every 11 …

    View Full Text

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.