Development↦Statistic Methodology↦Statistics in the Protocol↦The Hypothesis
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