What is it? Why is it important?

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

 

In the context of statistical hypothesis testing, researchers formulate two competing hypotheses:

  • A null hypothesis - also referred to as H0: claims that the treatment effect does not exist. (e.g. see example below).,
  • An alternative hypothesis - also referred to as Ha: claims the existence of a treatment effect

 

Example: in a study assessing the effect of a new medication on blood pressure:

  • H0: “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
  • Ha:  the treatment is causing a change in blood pressure

 

Data collected during study conduct are used to implement a statistical test and decide whether there is enough evidence to reject H0 in favour of Ha.

What do I need to do?

As a SP-INV, determine whether your research question requires statistical hypothesis testing for the main outcome (primary endpoint).

 

In simple terms: Can I answer my main research question by just describing the data, or do I need a statistical test to determine whether an observed difference/relationship is statistically significant?

 

Conclusion: If you need to conduct a statistical test, you need to define H0 and Ha.

Where can I get help?

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
Abbreviations
  • 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