All-cause mortality
Deaths from any cause during a stated follow-up period. It avoids relying on cause-of-death classification, but the time period and population still matter.
Definition and caveats41 terms · facts kept separate from jokes
Words that deserve a second look.
Read the factual definition first. A clearly labeled analogy follows; it is there for the smile, not for evidence.
41 of 41 terms
HR
Hazard ratio: a comparison of the instantaneous event rates between groups among participants who have not yet had the event. It is not generally the same as a ratio of cumulative probabilities.
Definition and caveatsRR
Relative risk (risk ratio): the probability of an outcome in one group divided by the probability in another over a specified period.
Definition and caveatsOR
Odds ratio: the odds of an outcome in one group divided by the odds in another. When outcomes are common, it can look farther from 1 than the corresponding risk ratio.
Definition and caveatsIRR
Incidence rate ratio: a ratio between event rates, usually events per person-time, in two groups.
Definition and caveatsRaR
Rate ratio: a ratio of two event rates. The exact meaning of “rate” depends on the measured outcome and study design.
Definition and caveatsStandardized mortality ratio
Observed deaths divided by expected deaths calculated from a chosen reference population, often after accounting for age or other factors.
Definition and caveatsRisk difference
The probability of an outcome in one group minus the probability in another. It expresses an absolute difference over the stated period.
Definition and caveats95% CI
A 95% confidence interval is produced by a method that, under its assumptions, would cover the true parameter in about 95% of repeated samples. It is not a 95% probability statement about this one fixed interval.
Definition and caveatsRCT
Randomized controlled trial: participants are assigned to study groups by chance, which can reduce confounding. Randomization does not fix every issue with adherence, measurement or generalizability.
Definition and caveatsMeta-analysis
A statistical method for combining estimates from multiple studies. Its result depends on which studies were included and how their differences were handled.
Definition and caveatsCohort
A group of people sharing a defined characteristic or starting point, followed to observe outcomes. Cohort studies can be prospective or retrospective.
Definition and caveatsObservational study
A study in which researchers observe exposures and outcomes without assigning the exposure as an intervention.
Definition and caveatsConfounding
A distortion in an exposure–outcome association caused by another factor related to both the exposure and the outcome.
Definition and caveatsReverse causation
The apparent direction of an association may be reversed: the outcome or an early stage of it affects the exposure, rather than the exposure causing the outcome.
Definition and caveatsd and g
Cohen’s d and Hedges’ g are standardized mean differences, expressing a difference between group means in standard-deviation units. Hedges’ g includes a small-sample correction.
Definition and caveatsCorrelation coefficient (r)
Pearson’s r measures the direction and strength of a linear association between two variables, from −1 to 1. Correlation does not by itself establish causation.
Definition and caveatsMET
Metabolic equivalent of task: a way to express activity energy use relative to resting energy use. MET values are estimates and vary among people and activities.
Definition and caveatsGRADE
A framework used to assess certainty in a body of evidence and strength of recommendations across outcomes.
Definition and caveatsIntention-to-screen analysis
An analysis that compares people according to whether they were invited or assigned to screening, rather than only comparing those who attended. It preserves the invitation strategy being evaluated.
Definition and caveatsPack-years
A cumulative smoking-exposure measure calculated as packs smoked per day multiplied by years smoked; for example, one pack daily for ten years is ten pack-years.
Definition and caveatsBMI
Body mass index: weight in kilograms divided by height in metres squared. It is a screening measure and does not directly measure body fat or diagnose an individual.
Definition and caveatsLDL
Low-density lipoprotein particles carry cholesterol in the blood. Higher LDL cholesterol is associated with atherosclerotic cardiovascular risk; treatment decisions depend on overall risk and clinical context.
Definition and caveatseGFR
Estimated glomerular filtration rate: a calculation using blood markers and other variables to estimate kidney filtering function. A single value does not on its own establish chronic kidney disease.
Definition and caveatsHBsAg
Hepatitis B surface antigen. A positive result can indicate current hepatitis B virus infection and needs interpretation with other tests and clinical context.
Definition and caveatsHPV
Human papillomavirus: a large group of viruses. Persistent infection with certain high-risk types can cause cervical and other cancers; many infections clear without causing disease.
Definition and caveatsLDCT
Low-dose computed tomography: a CT scan protocol using a lower radiation dose than a standard diagnostic chest CT, used in certain lung-cancer screening programs.
Definition and caveatsPM2.5
Airborne particles with an aerodynamic diameter of 2.5 micrometres or smaller. Exposure is associated with health risks, with effects depending on concentration and duration.
Definition and caveatsNOVA classification
A system that groups foods by the nature, extent and purpose of processing. It describes processing categories; it is not by itself a complete nutritional-quality score.
Definition and caveatsLoan Prime Rate (LPR)
China’s Loan Prime Rate is a lending-rate reference published through the national quotation mechanism. Actual loan pricing and legal effects depend on contract terms and current rules.
Definition and caveatsOne-arbitration-final
In specified labor-dispute cases under Mainland China law, an arbitration award may take effect as final at the first instance, subject to statutory procedures and exceptions.
Definition and caveatsCrude marriage and divorce rates
Counts of registered marriages or divorces in a period divided by the population, commonly expressed per thousand people. A divorce-to-marriage count ratio is a different measure and does not track the outcomes of the same couples.
Definition and caveatsAED
Automated external defibrillator. It analyzes heart rhythm and gives voice or visual prompts; the user follows the device and emergency dispatcher instructions.
Definition and caveatsCPR
Cardiopulmonary resuscitation: emergency actions, including chest compressions and sometimes rescue breaths, used when a person is in cardiac arrest.
Definition and caveatsChina Compulsory Certification (CCC)
China’s compulsory product-certification system. Products within the applicable catalogue must meet the relevant certification requirements before specified import, sale or use.
Definition and caveatsICP filing
A Mainland China internet-information-service filing process for services covered by current rules. Whether filing, licensing or another requirement applies depends on the service and operator.
Definition and caveatsMulti-Level Protection Scheme
Mainland China’s cybersecurity classification and protection framework for network systems, with duties depending on system level and applicable rules.
Definition and caveatsGPL
A family of free-software licenses with copyleft terms. Obligations depend on the exact version, how the code is combined and whether a covered work is conveyed or distributed.
Definition and caveatsNon-compete
A contractual restriction on certain work or business activity for a period after employment. Enforceability, eligible workers, compensation and limits depend on the jurisdiction and agreement.
Definition and caveatsSubscribed capital
Capital shareholders commit to contribute to a company. Contribution duties, deadlines and liability depend on the company law and registration regime that apply.
Definition and caveatsDeposit vs. prepayment
A deposit may secure performance and carry specific legal consequences, while an advance payment is generally money paid ahead of performance. The label, contract and governing law matter.
Definition and caveatsHealth, statistics and Mainland China legal terms are simplified reading aids. Follow each term’s scope note and open the cited source entry before using it in a decision.