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Observational Study

In epidemiology and statistics, an observational study draws conclusions about the possible effect of a treatment on participants, where the assignment of participants into a treatment group versus a control group is outside the control of the investigator.

However, in some cases observational studies are the most appropriate design for example if the condition being studied is rare. Additionally, non-interventional observational studies are sometimes the only ethical approach. For example, if the effect of an environmental risk factor (such as asbestos) is being studied, it is unethical to deliberately expose participants to that risk factor.

In a non-interventional observational study, no additional diagnostic or monitoring procedures are applied to the participants, and epidemiological methods are used for the analysis of collected data (as per Article 2(c) of 2001/20/EC). A non-interventional observational study is not a randomised, controlled trial (RCT).

&nbsp,non-interventional observational studies,Non-interventional observational study

Observer Bias

Observer bias (also called ascertainment or detection bias) is caused when the actions of an investigator affect the results of a trial. Observer bias can be unintentional and could arise from the investigator's hopes or expectations of the trial. It is most likely to occur when:

  • the investigator's personal judgement is used to measure subjective trial outcomes, and
  • the investigator knows which group each person is allocated to (for example treatment or placebo).

The most important design technique for avoiding observer bias in clinical trials is blinding. The potential effect of bias should also be taken into account during statistical analysis of trial data.

Observer-reported outcome

A measurement based on an observation by someone other than the patient or a health professional such as a parent, or other non-clinical caregiver who regularly observes the patient in daily life and is in a position to report on a specific aspect of the patient™s health.

This type of measure or observer report is without medical judgment or interpretation, and includes events or behaviours that can be observed in patients who cannot communicate themselves (e.g. infants or cognitively impaired).

Oestrogen Receptors (Estrogen Receptors)

Oestrogen Receptors (Estrogen Receptors)

Off label use

Off-label use refers to situations where a medicinal product is intentionally used for a medical purpose other than what is stated in the authorised product information, i.e. the Summary of Product Characteristics (SmPC).

Examples of off-label use include non-authorised:

Official Medicines Control Laboratory

An Official Medicines Control Laboratory (OMCL) is a public institution which performs laboratory testing on medicines once they are on the market. They are an essential part of the European system of controlling the quality of medicines.

OMCLs are appointed by national competent authorities. OMCLs carry out testing for their competent authority, independently from the manufacturer of the medicine. OMCLs in Europe collaborate with each other in order to pool resources and share best practice.

Omics technologies

The 'Omics technologies are relatively recent fields of study such as genomics, proteomics, or metabolomics. They deal with large amounts of data because they assess entire genomes, proteomes, or metabolomes. Information technology (IT) is therefore a crucial element in 'omics research.


An oncogene is a mutated gene that contributes to the development of a cancer. In their normal, non-mutated state, oncogenes are called proto-oncogenes, and they are important in the regulation of cell growth. When altered, an oncogene can either promote or allow the uncontrolled growth of cancer. Alterations can be inherited or caused by exposure to carcinogens (cancer-causing substances).

Orodispersible tablet

A tablet designed to be dissolved in the mouth rather than swallowed whole.

Orphan designation

Orphan designation is a special status for a medicine used to treat a rare disease or condition. An orphan designation is adopted by the Committee for Orphan Medicinal Products (COMP) of the European Medicines Agency (EMA) and confirmed by the European Commission (EC) before the granting of marketing authorisation.

To qualify for orphan designation, a medicine must meet a number of criteria:

(1) It must be intended for the treatment, prevention or diagnosis of a disease that is life-threatening or chronically debilitating.

(2) The condition must affect no more than 5 in 10,000 people in the EU, or it must be unlikely that sales of the medicine will be sufficient to justify the investment needed for its development.

(3) No satisfactory method of diagnosis, prevention or treatment of the condition exists, or, if it does, the medicine in question must provide a significant benefit to those affected by the condition.

Developers of medicines who obtain orphan designation benefit from a number of incentives. Incentives include specific scientific advice and 10-year market exclusivity. Market exclusivity means that, during this period, no other medicine for the same condition will be granted market authorisation. Reduced fees for applications for services from the European Medicines Agency (EMA) may also be available.

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