• Scientific reproducibility

    Obtaining consistent results when research is conducted by a separate researcher using the same study design, methodology, and analysis. [Adapted from]

  • Scientific rigor

    The application to research of a well-thought-out plan and a methodology based on best practice in order to minimize bias. [Adapted from]

  • Signal 1, Signal 2

    The primary and secondary cell signals necessary for the immune system to activate. Signal 1 is the interaction between the antigen-presenting cell and the T-cell through a connection between the major histocompatibility complex (MHC) and a T-cell receptor. Signal 2 can be any number of connections formed by the molecules and receptors on the surfaces of both the antigen-presenting cell and the T-cell. [Patient Resource LLC]

  • Signaling pathway

    Describes a group of molecules in a cell that work together to control one or more cell functions, such as cell division or cell death. After the first molecule in a pathway receives a signal, it activates another molecule. This process is repeated until the last molecule is activated and the cell function is carried out. Abnormal activation of signaling pathways can lead to cancer, and drugs are being developed to block these pathways. These drugs may help block cancer cell growth and kill cancer cells. [NCI]

  • SNP

    Short for single nucleotide polymorphism. The most common type of change in DNA (molecules inside cells that carry genetic information). SNPs occur when a single nucleotide (building block of DNA) is replaced with another. These changes may cause disease, and may affect how a person reacts to bacteria, viruses, drugs, and other substances. [NCI]

  • Somatic mutation

    An alteration in DNA that occurs after conception. Somatic mutations can occur in any of the cells of the body except the germ cells (sperm and egg) and therefore are not passed on to children. These alterations can (but do not always) cause cancer or other diseases. [NCI]

  • Standard of care

    A treatment regimen that is accepted by medical experts and is widely used as a treatment for a specific type of cancer. This can also be called best practice, standard medical care and standard therapy. [Patient Resource LLC]

  • Statistically significant

    Describes a mathematical measure of difference between groups. The difference is said to be statistically significant if it is greater than what might be expected to happen by chance alone. Also called significant. [NCI]

    Scientists use the term “p” to describe the probability of observing such a large difference purely by chance in groups of like people and this is known as the “p-value.” Mathematical probabilities like p-values range from 0 (no chance) to 1 (absolute certainty). So 0.5 means a 50 per cent chance and 0.05 means a 5 per cent chance. In most sciences, results yielding a p-value of .05 are considered on the borderline of statistical significance. If the p-value is under .01, results are considered statistically significant and if it’s below .005 they are considered highly statistically significant. [From:]

  • Surveillance

    In medicine, closely watching a patient’s condition but not treating it unless there are changes in test results. Surveillance is also used to find early signs that a disease has come back. It may also be used for a person who has an increased risk of a disease, such as cancer. During surveillance, certain exams and tests are done on a regular schedule. In public health, surveillance may also refer to the ongoing collection of information about a disease, such as cancer, in a certain group of people. The information collected may include where the disease occurs in a population and whether it affects people of a certain gender, age, or ethnic group. [NCI]

  • Survival rate

    The percentage of people in a study or treatment group who are still alive for a certain period of time after they were diagnosed with or started treatment for a disease, such as cancer. The survival rate is often stated as a five-year survival rate, which is the percentage of people in a study or treatment group who are alive five years after their diagnosis or the start of treatment. Also called overall survival rate. [NCI]