Screening (medicine) in the context of "Rapid diagnostic test"

In public health, contact tracing is the process of identifying people who may have been exposed to an infected person ("contacts") and subsequent collection of further data to assess transmission. By tracing the contacts of infected individuals, testing them for infection, and isolating or treating the infected, this public health tool aims to reduce infections in the population. In addition to infection control, contact tracing serves as a means to identify high-risk and medically vulnerable populations who might be exposed to infection and facilitate appropriate medical care. In doing so, public health officials utilize contact tracing to conduct disease surveillance and prevent outbreaks. In cases of diseases of uncertain infectious potential, contact tracing is also sometimes performed to learn about disease characteristics, including infectiousness. Contact tracing is not always the most efficient method of addressing infectious disease. In areas of high disease prevalence, screening or focused testing may be more cost-effective.

The goals of contact tracing include:

Prostate cancer is the uncontrolled growth of cells in the prostate, a gland in the male reproductive system below the bladder. Abnormal growth of the prostate tissue is usually detected through screening tests, typically blood tests that check for prostate-specific antigen (PSA) levels. Those with high levels of PSA in their blood are at increased risk for developing prostate cancer. Diagnosis requires a biopsy of the prostate. If cancer is present, the pathologist assigns a Gleason score; a higher score represents a more dangerous tumor. Medical imaging is performed to look for cancer that has spread outside the prostate. Based on the Gleason score, PSA levels, and imaging results, a cancer case is assigned a stage 1 to 4. A higher stage signifies a more advanced, more dangerous disease.

Most prostate tumors remain small and cause no health problems. These are managed with active surveillance, monitoring the tumor with regular tests to ensure it has not grown. Tumors more likely to be dangerous can be destroyed with radiation therapy or surgically removed by radical prostatectomy. Those whose cancer spreads beyond the prostate are treated with hormone therapy which reduces levels of the androgens (masculinizing sex hormones) which prostate cells need to survive. Eventually cancer cells can grow resistant to this treatment. This most-advanced stage of the disease, called castration-resistant prostate cancer, is treated with continued hormone therapy alongside the chemotherapy drug docetaxel. Some tumors metastasize (spread) to other areas of the body, particularly the bones and lymph nodes. There, tumors cause severe bone pain, leg weakness or paralysis, and eventually death. Prostate cancer prognosis depends on how far the cancer has spread at diagnosis. Most men diagnosed have low-risk tumors confined to the prostate; 99% of them survive more than 10 years from their diagnoses. Tumors that have metastasized to distant body sites are most dangerous, with five-year survival rates of 30–40%.

Cytopathology (from Greek κύτος, kytos, "a hollow"; πάθος, pathos, "fate, harm"; and -λογία, -logia) is a branch of pathology that studies and diagnoses diseases on the cellular level. The discipline was founded by George Nicolas Papanicolaou in 1928. Cytopathology is generally used on samples of free cells or tissue fragments, in contrast to histopathology, which studies whole tissues. Cytopathology is frequently, less precisely, called "cytology", which means "the study of cells".

Cytopathology is commonly used to investigate diseases involving a wide range of body sites, often to aid in the diagnosis of cancer but also in the diagnosis of some infectious diseases and other inflammatory conditions. For example, a common application of cytopathology is the Pap smear, a screening tool used to detect precancerous cervical lesions that may lead to cervical cancer.

A medical test is a medical procedure performed to detect, diagnose, or monitor diseases, disease processes, susceptibility, or to determine a course of treatment. Medical tests such as, physical and visual exams, diagnostic imaging, genetic testing, chemical and cellular analysis, relating to clinical chemistry and molecular diagnostics, are typically performed in a medical setting.

In medicine and statistics, sensitivity and specificity mathematically describe the accuracy of a test that reports the presence or absence of a medical condition. If individuals who have the condition are considered "positive" and those who do not are considered "negative", then sensitivity is a measure of how well a test can identify true positives and specificity is a measure of how well a test can identify true negatives:

• Sensitivity (true positive rate) is the probability of a positive test result, conditioned on the individual truly being positive.
• Specificity (true negative rate) is the probability of a negative test result, conditioned on the individual truly being negative.

If the true status of the condition cannot be known, sensitivity and specificity can be defined relative to a "gold standard test" which is assumed correct. For all testing, both diagnoses and screening, there is usually a trade-off between sensitivity and specificity, such that higher sensitivities will mean lower specificities and vice versa.

The Mantoux test (also called the Mendel–Mantoux test, tuberculin sensitivity test, or PPD test) is a method used to screen for tuberculosis (TB) infection. It has largely replaced older skin testing techniques such as the tine and Heaf tests. The test involves injecting a small amount of purified protein derivative (PPD) tuberculin just under the skin of the forearm. If performed correctly, the injection creates a small, pale bump called a wheal. The test site is examined a few days later for swelling or hardening of the skin, an immune response that would be expected if the person had been exposed to tuberculosis. However, additional tests are usually required to confirm active infection.

Preconception counseling (also called preconceptual counseling) is an informative discussion with a healthcare professional (generally a physician or advanced practice provider) by an individual, with or without support people, who is interested in a future pregnancy. The goal of preconception care is to educate people on the importance of health optimization prior to pregnancy to reduce the risk for pregnancy complications and promote a healthy intrauterine environment for normal fetal growth and development. It generally includes a preconception risk assessment for any potential complications of pregnancy as well as modifications of risk factors, such as increasing folic acid intake to reduce the risk of neural tube defects and counseling on smoking cessation, alcohol reduction, and medications that may compromise fetal development. Physicians, midwives and baby experts recommend that an individual should visit them as soon as a person is contemplating having a child, and optimally at least 3 to 6 months before actual attempts are made to conceive. This time frame allows a woman to better prepare her body for successful conception (fertilization) and pregnancy, and allows her to reduce any health risks which are within her control. Agencies such as the March of Dimes have developed screening tools that healthcare providers can use with their patients. In addition, obstetricians or midwives (see Obstetrics, Midwifery, General Practitioner) have developed comprehensive check-lists and assessments for the woman who is planning to become pregnant.

In one sense, pre-conception counseling and assessment can be compared to a well-baby visit in which a baby is screened for normal health, normal development, with the benefit of identifying emerging problems that may have gone unnoticed in an infant. For a woman, the Pre-Conception Counseling Assessment and Screening is intended to assess normal health of a child-bearing woman, while at the same time identifying:

Hepatology is the branch of medicine that incorporates the study of liver, gallbladder, biliary tree, and pancreas as well as management of their disorders. Although traditionally considered a sub-specialty of gastroenterology, rapid expansion has led in some countries to doctors specializing solely on this area, who are called hepatologists.

Diseases and complications related to viral hepatitis and alcohol are the main reason for seeking specialist advice. More than two billion people have been infected with hepatitis B virus at some point in their life, and approximately 350 million have become persistent carriers. Up to 80% of liver cancers can be attributed to either hepatitis B or hepatitis C virus. In terms of mortality, the former is second only to smoking among known agents causing cancer. With more widespread implementation of vaccination and strict screening before blood transfusion, lower infection rates are expected in the future. In many countries, however, overall alcohol consumption is increasing, and consequently the number of people with cirrhosis and other related complications is commensurately increasing.

Phenotypic screening is a type of screening used in biological research and drug discovery to identify substances such as small molecules, peptides, or RNAi that alter the phenotype of a cell or an organism in a desired manner. Phenotypic screening must be followed up with identification (sometimes referred to as target deconvolution) and validation, often through the use of chemoproteomics, to identify the mechanisms through which a phenotypic hit works.