The Short Answer: Nope! 🙅🏾‍♀️ The goal of a screening test is to determine the likelihood of disease in a person who currently shows no signs or symptoms, while a diagnostic test detects whether (and what type of) disease might be present in someone with symptoms.
While some screening tests can be self-administered at home or under professional supervision, diagnostic tests are always administered by healthcare providers and often help you and your care team determine how to move forward in creating a treatment plan (if needed).
The Longer Answer: Screening tests and diagnostic tests differ in several key ways. Screening tests have two main purposes: (1) to detect disease early on in asymptomatic individuals and (2) to identify individuals and populations who are at an increased risk of developing a disease and may be in need of further monitoring. Many screening tests are non-invasive, meaning that they do not require a nurse or doctor to draw your blood. Mammographies, for instance, use low-energy x-ray techniques to examine your breast for tumors and other potential breast diseases. Some of the recommendations you might receive following a screening like this include undertaking a more balanced lifestyle (lowering your stress levels, adjusting your diet or sleep schedule, and engaging in more physical activity); getting screened more often so that an emerging disease can be detected and treated as early as possible; and heading to a specialist who can either confirm or rule out whether you have a disease.
Diagnostic tests are often given as follow-ups to screening tests when something potentially abnormal has been detected. While a screening test gives insight into whether a person without symptoms has a disease (or is likely to have a disease in the future), a diagnostic test tries to conclude whether you actually have the disease. If, for example, a mammography produces an image of your breast that your doctor thinks needs a closer look, then you might be referred to receive a follow-up diagnostic exam known as a biopsy. During a biopsy, a specialist takes a tiny sample of tissue from your body and sends it to a lab. In turn, the lab will not only determine whether any of your tissue cells are cancerous, but it can also pinpoint the type of cancer you have based on where in your body the cancer started growing. A doctor may order a diagnostic test for you straight away if you are already presenting symptoms of a disease, so if you aren’t feeling well, there are options to skip the “screening stage” to get a faster diagnosis and begin treatment as needed.
Can I self-administer my screening or diagnostic test, or do I have to go to my doctor’s office?
There are some screening tests that you can give yourself from the comfort of your own home, such as a breast self-exam in the shower. During such exams, you determine whether you see or feel anything out of sorts that might be worth scheduling a doctor’s appointment. Other screening tests allow you to collect your own sample under the supervision of your healthcare provider. You can take your own cervical screening test, which looks at a sample of cells from your cervix, using a long cotton swab. As long as you follow the instructions given by your healthcare provider, self-collection is typically just as effective and accurate as if the provider were to swab you themselves. ✅
Though you cannot self-administer a diagnostic test, if you begin experiencing disease symptoms or sense any abnormalities during a self-exam, you can always visit your healthcare provider to determine whether you should move forward with diagnostic testing. Don’t be afraid to listen to your body and tune into your intuition! 🕵🏽
Some screening tests, such as mammograms and prenatal ultrasounds, involve a professional capturing images of your body to detect abnormalities that you wouldn’t be able to see or feel during a self-exam. Finally, pelvic exams and pap smears (which screen for cancer in the cervix) are screening tests that must be given by your healthcare provider to determine the health of your internal and external reproductive organs. If you are experiencing any sort of discomfort in your pelvic area – whether you are sexually active or not – don’t be afraid to check-in with your doctor about receiving a screening to make sure that everything is in good shape.
Stay safe, stay well!
Those Nerdy Girls
Additional Resources:
Guides on how to distinguish screening tests from diagnostic tests:
Cleveland Clinic: Screening vs. Diagnostic Testing
UCLA Health: The difference between screening and diagnostic tests
Health checks you can give yourself at home
Common screening tests administered by your doctor
Key questions to ask your healthcare provider before, during, and after testing
