Use common sense when you test yourself

22 March 2017, Updated 06 April 2017

The Danish Medicines Agency has launched a campaign recommending you to use your common sense when you use self-tests and apps to test yourself for diseases. Look for the CE mark when you test yourself, and consult your doctor in case of doubt.

HPV tests, depression test apps and genetic tests calculating the probability of developing cancer and other diseases are some of the many home tests and self-tests that have been placed on the market during the past years. In many cases, it may be an easy and convenient way to test yourself for various diseases. However, it is important to bear in mind that not all self-tests are equally good; they may not comply with the applicable rules, and a self-test cannot replace a visit to your doctor. When you test yourself, always remember:

  • To use your common sense – and consult your doctor if you are unsure whether you are healthy
  • To use CE marked self-tests

Use your common sense when you test your health

You should always apply your common sense and natural scepticism when you test yourself for diseases. Even though a test may have established a diagnosis or given you the answers to questions about your health, you should always consult your doctor if you feel unwell or are unsure whether you are healthy.

Look out for the CE mark on tests you are using

When you select self-tests, the rule of thumb is to look out for the CE mark. The CE mark means that the test complies with the rules that apply to the specific type of product. In other words, the CE mark is your guarantee that the test is safe to use and that it can do what it claims it can do.

What is the CE mark?

You may have seen it on toys, electrical appliances, bicycle helmets and child safety seats. When a test or a product is CE marked, it means that the manufacturer of the test documents that the product meets the legal requirements. Moreover, the CE mark means that the product is safe to use and that it can do what the manufacturer claims it can do. This is how the official CE mark looks:

CE mærke

Which self-tests are CE marked?

Some self-tests belong to the category medical devicesthey must always be CE marked. Medical devices are products, which are used for the diagnosis, prevention, relief or treatment of a disease, disability, injury etc.

Medical devices include products for professional use (e.g. X-ray devices, scanners, needles and surgical instruments) and for home use (e.g. insulin pumps, patches and wheelchairs). But medical devices also include apps or tests where you use your own saliva or blood to make a diagnosis or treat a disease. Such tests are known as home-use tests or self-tests.

Medical devices are not authorised by the Danish Medicines Agency. However, they must be CE marked, before they are placed on the market.

Are health apps CE marked?

There are many health apps available for download. But many of these health apps do not have a specific medical purpose and consequently they are not considered medical devices. Examples are sport apps, calorie counter apps, apps reminding you to take your medicine, symptom tracker apps or apps that exclusively send health data to your own doctor. These health apps are not medical devices and need not be CE marked.

It is important to bear in mind that the manufacturer determines the purpose of an app, test or other device. An app measuring your heart rate when you are running does not become a medical device if somebody uses it in an emergency. The purpose of the device determines whether it should be CE marked as a medical device.

Are pregnancy tests and ovulation tests also medical devices?

Pregnancy and ovulation tests, diabetes test strips for blood glucose testing and similar products belong to a group of devices named IVD devices (in vitro diagnostic devices). IVD medical devices are products used to examine samples from humans. The samples may be blood, saliva, urine or tissue. Hospitals and general practitioners use many different types of IVD devices. Some IVD tests can also be used to determine whether you suffer from a specific disease or whether you have a high or low risk of developing certain diseases. IVD devices are also CE marked.

Are self-tests dangerous?

Just like medicine may have adverse reactions, there may be risks associated with using medical devices for self-tests. The company manufacturing the test must make sure that the advantages of using the test outweigh any possible risks, and the manufacturer must provide information about any potential risks of the product. In addition, the manufacturer must provide good guidelines on how to use the test.

Since medical devices cover many different products – more than half a million – they are divided into classes.

There are four classes (class I, classes IIa and IIb and class III).

  • Class I cover the products associated with the lowest risk
  • Class III is associated with the highest risk

The risk depends on how often the device is used, for how long time it is used, where on the body it is used, whether it enters the body etc.

Many of the tests you can buy on the market are typically low-risk devices.

3 tips


  • Use your common sense when you test yourself for diseases
  • Consult your doctor if you feel unwell or worry that you are ill
  • Look out for the CE mark when you test yourself