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Home > Read or listen to the book > What are fair tests of treatments? > Fair tests of treatments > Comparing like with like > Treatments with moderate but important effects

Treatments with moderate but important effects

Download a pdf of Treatments with moderate but important effects

This section addresses the common situation in which treatments may differ only moderately from each other, but these differences may nevertheless be important. In these circumstances we need to consider how to get valid estimates of these differences.

In this sub-section:

A variety of study designs have been used, including:

  • Comparing patients given treatments today with apparently similar patients given other treatments in the past for the same disease
  • Comparing apparently similar groups of patients who happen to have received different treatments in the same time period
  • Unbiased, prospective allocation to different treatments
  • Ways of using unbiased (random) allocation in treatment comparisons
  • Following up everyone in treatment comparisons
  • Dealing with departures from allocated treatments
  • Helping people to stick to allocated treatments

In This Section

  • About
    • About the book
      • About the authors
      • Download the book
      • Reviews
      • Translations
    • Why do we need fair tests of treatments?
    • What are fair tests of treatments?
    • What can be done to improve tests of treatments?
  • Background
    • Foreword by Ben Goldacre
      • References (Foreword)
    • Foreword by Nick Ross
    • Why Testing Treatments was written
    • Introduction
      • References (Introduction)
  • Why are fair tests of treatments needed?
    • New – but is it better?
      • Thalidomide
      • Vioxx
      • Avandia
      • Mechanical heart valves
      • Herceptin
      • References (Section 1)
    • Hoped-for effects that don’t materialize
      • Advice on babies’ sleeping position
      • Drugs to correct heart rhythm abnormalities in patients having a heart attack
      • Diethylstilboestrol
      • Hormone Replacement Therapy (HRT)
      • Evening primrose oil for eczema
      • References (Section 2)
    • More is not necessarily better
      • Intensive treatments for breast cancer
        • Mutilating surgery
        • Bone marrow transplantation
      • Dare to think about doing less
      • References (Section 3)
    • Earlier is not necessarily better
      • Lessons from neuroblastoma screening
      • Weighing benefits and harms
        • Phenylketonuria screening: clearly beneficial
        • Abdominal aortic aneurysm screening: proceed with care
        • Breast cancer screening: well established but remains contentious
        • Prostate cancer screening: clear harms with uncertain benefits
        • Lung cancer screening: early but not early enough?
        • Genetic tests: sometimes useful, often dodgy
      • What screening aims to achieve and why evidence matters
      • Is anyone normal?
      • References (Section 4)
    • Dealing with uncertainty about the effects of treatments
      • Dramatic treatment effects: rare and readily recognizable
        • Laser treatment of portwine stains
        • Imatinib for chronic myeloid leukaemia
        • Mother’s kiss
        • A new treatment for strawberry birthmarks
      • Moderate treatments effects: usual and not so obvious
      • When practitioners disagree
        • Caffeine for breathing problems in premature babies
        • Antibiotics in pre-term labour
        • Breast cancer
      • Addressing uncertainties about the effects of treatments
      • Providing treatment as part of a fair test
      • References (Section 5)
  • What are fair tests of treatments?
    • Fair tests of treatments
      • Why are fair tests of treatments needed?
        • The beneficial effects of optimism and wishful thinking
        • The need to go beyond impressions
        • So what are fair tests?
      • Comparing like with like
        • Treatments with dramatic effects
        • Treatments with moderate but important effects
          • Comparing patients given treatments today with apparently similar patients given other treatments in the past for the same disease
          • Comparing apparently similar groups of patients who happen to have received different treatments in the same time period
          • Unbiased, prospective allocation to different treatments
          • Ways of using unbiased (random) allocation in treatment comparisons
          • Following up everyone in treatment comparisons
          • Dealing with departures from allocated treatments
          • Helping people to stick to allocated treatments
      • Fair measurement of treatment outcomes
      • Generating and investigating hunches about unanticipated adverse effects of treatments
      • References (Section 6)
    • Taking account of the play of chance
      • Assessing the role that chance may have played in fair tests
      • What does a “significant difference” between treatments mean?
      • Obtaining large enough numbers in fair tests of treatments
      • References (Section 7)
    • Assessing all the relevant, reliable evidence
      • Is one study ever enough?
      • Systematic reviews of all the relevant, reliable evidence
        • Reducing biases in systematic reviews
        • Identifying all the relevant evidence for systematic reviews
        • Reducing the play of chance in systematic reviews
        • Recognizing vested interests and spin in systematic reviews
      • What can happen if all the relevant, reliable evidence is not assessed?
        • Avoidable harm to patients
        • Avoidable harm to people participating in research
        • Wasted resources in healthcare and research
      • Reports of new research should begin and end with systematic reviews
      • References (Section 8)
  • What can we do to improve tests of treatments?
    • Regulating tests of treatments: help or hindrance?
      • Do regulatory systems for testing treatments get it right?
      • Information and consent
      • What regulatory systems do not do
      • References (Section 9)
    • Research – good, bad and unnecessary
      • Good research
        • Stroke
        • Pre-eclampsia in pregnant women
        • HIV infection in children
      • Bad research
        • Psychiatric disorders
        • Epidural analgesia for women in labour
      • Unnecessary research
        • Respiratory distress in premature babies
        • Stroke
        • Aprotinin: effect on bleeding during and after surgery
      • Distorted research priorities
        • Questions that are important for patients
        • Who decides what gets studied?
      • References (Section 10)
    • Getting the right research done is everybody’s business
      • How can patients and the public help to improve research?
      • Involving patients in research
      • How patients can jeopardize fair tests of treatments
        • Patients’ organizations: independent voices or not?
        • Bridging the gap between patients and researchers
      • Working collaboratively bodes well for the future
      • References (Section 11)
    • So what makes for better healthcare?
      • What might the ideas in this website look like for you?
      • Shared decision making: a consultation for a common condition
      • Questions about translating research evidence into practice
        • 1: Isn’t anything worth trying when a patient has a life-threatening condition?
        • 2: Although patients might want to know if a treatment ‘works’, suppose they don’t want all the details?
        • 3: Statistics are confusing – should patients really have to look at the numbers?
        • 4: How can someone know that the research evidence applies to them?
        • 5: Won’t genetic testing – and ‘personalized medicine’ – mean doctors can work out the specific treatment needed in every individual and make all this unnecessary?
        • 6: If someone has a condition that is being studied in an ongoing clinical trial, how do they find out about this if their doctor doesn’t know about it?
        • 7: What’s the best way of telling if the evidence (on the web or elsewhere) is reliable?
        • 8: Are there reliable sources of information that can be recommended?
        • 9: How should people avoid being ‘labelled’ with an ‘illness’ and getting unnecessary treatments?
      • Where do we go from here?
      • References (Section 12)
    • Research for the right reasons: blueprint for a better future
      • Ask the right research questions
      • Design and conduct research properly
      • Publish all the results and make them accessible
      • Produce unbiased and useful research reports
      • Blueprint for a better future
      • Action plan – 10 things you can do
      • References (Section 13)

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