Was betrifft es? Warum ist das wichtig?

A statistical hypothesis is an assumption about a parameter that is subject to empirical testing.

 

Example: a study assesses the effect of a new medication on blood pressure. The parameter in question is the participants`blood pressure.

 

Researchers establish a statistical hypothesis by formulating two competing hypotheses:

  • A null hypothesis - also referred to as H0: claims that the treatment effect does not exist. (e.g. based on the example above, H0 would be formulated as “There is no treatment effect on blood pressure” or, more specifically “There is no difference in blood pressure between participants of the intervention and control arm)
  •  represents a default assumption (i.e. no treatment effect exists. Based on the example above, no difference in blood pressure between the is detected)
  • An alternative hypothesis - also referred to as Ha: claims the existence of a treatment effect (e.g. based on the example above, treatment is causing a change in blood pressure)

 

Statistical analyses are used to assess the data collected in a study, enabling researchers to conclude whether H0 may or may not be rejected in favour of Ha.  

Was muss ich befolgen?

As a SP-INV, think about the statistical framework of your study (see the sample size calculation section),

If you need to conduct a statistical test to address your research question, you are in the hypothesis testing framework, and need to define H0 and Ha.

Example: a study aims at testing the effect of an intervention (e.g. blood pressure lowering drug) between a placebo and intervention group.

 

Wo kann ich Hilfe anfordern?

Your local Research Support Centre can assist you with experienced staff regarding this topic

  • Basel, Departement Klinische Forschung (DKF), dkf.unibas.ch

  • Lugano, Clinical Trials Unit (CTU-EOC), ctueoc.ch

  • Bern, Department of Clinical Research (DCR), dcr.unibe.ch

  • Geneva, Clinical Research Center (CRC), crc.hug.ch

  • Lausanne, Clinical Research Center (CRC), chuv.ch

  • St. Gallen, Clinical Trials Unit (CTU), h-och.ch

  • Zürich, Clinical Trials Center (CTC), usz.ch

SCTO Research Tools & Resources

References

ICH Topic E9 – see in particular

  • 5.5 Estimation, confidence intervals and hypothesis testing

Swiss Law

ClinO – see in particular article

  • Art. 2b Definition intervention

ClinO-MD – see in particular article

  • Art. 2a Definition of clinical intervention
  • Art. 2a Definition of performance study

HRO – see in particular article

  • Art. 3a Definition of research
Abkürzungen
  • ClinO – Clinical Trials Ordinance
  • ClinO-MD – Ordinance on Clinical Trials of Medical Devices
  • HRO – Human Research Ordinance
  • ICH – International Council for Harmonisation
  • SP-INV – Sponsor Investigator
  • H0 – Null hypothesis
  • Ha – Alternative Hypothesis
Development ↦ Statistic Methodology ↦ Statistics in the Protocol ↦ The Hypothesis
Study
Basic

Provides some background knowledge and basic definitions

Basic Monitoring
Concept

Starts with a study idea

Ends after having assessed and evaluated study feasibility

Concept Statistic Methodology
Concept Drug or Device
Development

Starts with confidence that the study is feasible

Ends after having received ethics and regulatory approval

Development Drug or Device
Set-Up

Starts with ethics and regulatory approval

Ends after successful study initiation

Set-Up Ethics and Laws
Set-Up Statistic Methodology
Set-Up Quality and Risk
Set-Up Drug or Device
Conduct

Starts with participant recruitment

Ends after the last participant has completed the last study visit

Conduct Statistic Methodology
Conduct Drug or Device
Completion

Starts with last study visit completed

Ends after study publication and archiving

Completion Drug or Device
Current Path (click to copy): Development ↦ Statistic Methodology ↦ Statistics in the Protocol ↦ The Hypothesis