| incidence | occurrence, rate, frequency of an undesirable thing |
| prevalence | how common a disease/condition is, commonness |
| diagnostic study | study to examine an individual(/population) to determine a disease, condition or illness. e.g. biopsy or prenatal testing |
| prognostic study | study in which a population is followed over a period of time, factors that might influence outcomes are measured over that period |
| observational study | study in which the effect of risk factors are observed, without interfering with it |
| experimental study | study where researchers introduce an intervention and study the effects. e.g. administering different drugs to different groups of patients and observing the effects |
| cross-sectional study | study where the data is collected at a certain time point from a sample population |
| longitudinal study | study with repeated observations of the same variables over a period of time. e.g. five-year study of children learning to read |
| ecological study | a type of observational study, but at population or group level, not at individual level. often used to measure prevalence of disease, especially when the condition is rare |
| case-control | type of observational study in which two groups that differ in outcome are identified. they are then compared to find something that caused the difference |
| cohort | a group of people that share a characteristic |
| sample | a group of people that are taken from a larger population |
| competing interests | anything that interferes with the objectivity of an article/publication. e.g. funding by someone who might profit |
| associated | related to, connected to |
| risk for | the possibility that something (bad) will happen |
| absolute risk | the ratio of people who have a condition compared to all the people who could have that condition at a certain time point. e.g. 40 have the condition and 200 do not, absolute riks is 20% |
| relative risk | the ratio of probability of an exposed group of people compared to a non-exposed group. e.g. risk of getting cancer for smokers and non-smokers. (comparing the risks of two groups). |
| internal validity | extent to which a study shows a trustworthy cause-and-effect relation between a treatment and outcome |
| external validity | extent to which the findings of a study are generalized to other situations and people, meaning are the results of a study also applicable to other situations |
| modifiable risk factor | factors, which can be changed, that can increase someone's chance to develop a certain condition. e.g. blood pressure |
| mortality risk / mortality rate | measure of the death in a certain population in relation to the size of that population per unit of time. e.g. units of death per 1000 individuals per year. so a mortality rate of 9.5 in a population of 1000 would mean 9.5 deaths per year. |
| informed consent | competently given consent after a professional explains the risks, benefits and alternatives of procedures |
| inclusion criteria | required features that people/patients must have to be able to participate in the study |
| pooled serum | the mixed serum of a number of individuals. serum is the fluid component of blood that does not play a role in blood clotting |
