Definition Of Terms

Definition Of Terms

The Long-Term Follow-Up Study is one of the largest epidemiological investigations of late effects outcomes of its kind. Many of the terms associated with epidemiological investigations are unfamiliar to study participants. This page will familiarize you with some of the terms you may hear as a participant in the LTFU.

Recruitment and retention When planning a study and determining who is to be included in the study, they invite potential participants to enroll. This phase is called recruitment. Investigators want people to stay in the study once they are recruited and enrolled and will look at their continued participation, or retention in the study.

What is an epidemiological investigation? The classic definition of epidemiology is the study of the distribution and determinants of health-related states and events in populations, and the application of this study to control of health problems. The LTFU is a large study of the distribution and associations of various health-related states found over time among survivors of childhood cancers.

What is a cohort study? A cohort study is a study that compares a group of people who share a common characteristic with another group that does not have the characteristic. The common characteristic might be a medical condition, a treatment, or even a behavior, like smoking. The participants in the LTFU Study share a common history of diagnosis and treatment for cancer or a similar illness during childhood or adolescence. For best results the people in the comparison group should be as similar as possible to the group being studied. In the LTFU, a certain number of participants were randomly chosen, like a flip of a coin, to invite one of their siblings (brothers and sisters) close to them in age to be in the control group for the cohort.

What is a sibling comparison group? Some siblings were invited to participate in the LTFU as a comparison group, sometimes called a control group. The sibling control group is similar to the LTFU cohort in almost every way except they did not receive treatment for cancer or a similar childhood illness. The health status of siblings and participants are followed over time. If survivors in the LTFU have a different health outcome when compared to their brothers and sisters, these results provide strong evidence about how cancer treatments affect long-term health. Siblings in our control group are very important to the success of the study.

What do you mean by late effects outcomes? The LTFU was designed to obtain health information at regular intervals from a select group of survivors of childhood cancer to determine if there was an increase in health problems later in life associated with certain chemotherapies or radiation treatments they received as treatment for the childhood cancer. The general term used for analyzing the development of adverse health problems is "late effects outcomes."

What is DNA banking? As part of the LTFU, investigators are asking participants to store some of the biological material (blood, saliva, buccal cells) for use in genetic studies in the future. Another term for storing the DNA is banking it, putting away for future use.