PGIM MD Community Medicine flashcards

35 cards. Read the term and the definition here. The deck at the top of this page is optional.

Incidence rate

The number of new cases of a disease arising in a defined population during a specified period, divided by the population at risk at the start of that period.

Prevalence

The proportion of a population that has a disease at a given point in time or during a period, counting both new and existing cases in the numerator.

Sensitivity

The proportion of people who truly have the disease and are correctly identified as positive by the test; calculated as true positives divided by true positives plus false negatives.

Positive predictive value

The probability that a person with a positive test result actually has the disease; it rises as disease prevalence in the tested population rises, unlike sensitivity and specificity.

Relative risk

The ratio of disease incidence among exposed persons to incidence among unexposed persons, estimated directly in cohort studies and interpreted as how many times exposure multiplies risk.

Herd immunity threshold

The proportion of a population that must be immune to interrupt sustained transmission, calculated as one minus one divided by the basic reproduction number R0.

Case-control study

An observational design that selects people with the outcome (cases) and comparable people without it (controls) and compares past exposure; it yields an odds ratio, not incidence.

Randomized controlled trial

An experimental design in which participants are randomly allocated to intervention or control groups, so that known and unknown confounders are balanced and causal inference is strongest.

Type I error

Rejecting a null hypothesis that is actually true, conventionally held at alpha 0.05; its probability is the significance level chosen before the analysis.

Confidence interval

A range of values around a sample estimate within which the true population value is expected to lie with a stated probability, usually 95%; width reflects precision.

Epidemic curve

A histogram of cases plotted by date or time of onset during an outbreak; a single sharp peak suggests a point source, while a rising series of peaks suggests person-to-person spread.

Confounding

Distortion of an exposure-outcome association by a third variable that is associated with both, and is not on the causal pathway; controlled by design or statistical adjustment.

Sampling error

The random difference between a sample estimate and the true population value, which decreases as sample size grows and is quantified by the standard error.

Standard error of mean

The standard deviation of the sampling distribution of the mean, equal to the population standard deviation divided by the square root of the sample size.

National Health Mission

India's umbrella programme, formed in 2013 by merging the rural and urban health missions, supporting primary care infrastructure, reproductive and child health, and disease control at state level.

Ayushman Bharat

India's flagship health reform with two arms: Health and Wellness Centres for comprehensive primary care, and PM-JAY insurance covering five lakh rupees per family per year.

Primary Health Centre norms

An Indian PHC is normed for 30,000 people in plains and 20,000 in hilly or tribal areas, staffed by medical officers and providing curative, preventive and referral services.

Universal Immunization Programme

India's national vaccination schedule covering BCG, hepatitis B, polio, pentavalent, measles-rubella, and DPT boosters, delivered through cold-chain-supported outreach sessions.

Vaccine vial monitor

A heat-sensitive label on a vaccine vial that darkens with cumulative heat exposure; when the inner square matches or outpaces the outer circle, the vial must be discarded.

Cold chain

The temperature-controlled system keeping vaccines at plus two to plus eight degrees Celsius from manufacture to administration, with polio vaccine stored frozen at minus twenty degrees.

Residual chlorine

The free chlorine remaining in treated water after disinfection, maintained at 0.2 to 0.5 milligrams per litre to protect against recontamination during distribution and storage.

Silicosis

A pneumoconiosis caused by inhaling respirable crystalline silica dust, producing progressive nodular fibrosis, often in miners, stone cutters and sandblasters; it predisposes to tuberculosis.

Byssinosis

An occupational lung disease from cotton, flax or hemp dust exposure in textile workers, causing Monday morning chest tightness and breathlessness that improves away from work.

Aedes aegypti

The day-biting mosquito that breeds in domestic water containers and transmits dengue, chikungunya, yellow fever and Zika; control relies on source reduction of standing water.

Maternal mortality ratio

Maternal deaths during pregnancy or within 42 days of termination, divided by live births in the same period and multiplied by 100,000; haemorrhage and hypertension are leading causes.

Infant mortality rate

Deaths of children under one year of age in a year divided by live births in that year, multiplied by 1,000; it reflects both health care and socioeconomic conditions.

Mid-upper arm circumference

A field measure of nutritional status in children aged 6 to 59 months; below 11.5 centimetres indicates severe acute malnutrition and below 12.5 centimetres moderate acute malnutrition.

Exclusive breastfeeding

Feeding an infant only breast milk, without water, other fluids or solids, for the first six months, followed by complementary foods with continued breastfeeding to two years.

Stunting

Low height for age resulting from chronic undernutrition and repeated infection; it is assessed by comparing a child's height with WHO growth reference standards.

DOTS

Directly observed treatment, short course: a tuberculosis strategy in which a trained observer watches the patient swallow each dose, supporting adherence and completion of the regimen.

Dengue warning signs

Persistent vomiting, abdominal pain, fluid accumulation, mucosal bleeding and lethargy appearing around defervescence, marking progression to severe dengue and the need for close monitoring.

Rabies post-exposure prophylaxis

Immediate wound washing with soap and running water for fifteen minutes, then rabies vaccine by schedule, plus immunoglobulin infiltrated around the wound for category three exposures.

Disease eradication

Permanent global reduction of a disease to zero cases, so that control measures can stop; smallpox is the only human disease achieved, with polio close to certification.

DALY

Disability-adjusted life year, one lost year of healthy life, calculated as years of life lost to premature death plus years lived with disability weighted for severity.

Cost-effectiveness analysis

An economic evaluation comparing interventions by cost per unit of health outcome, such as cost per case detected or per DALY averted, when outcomes cannot be monetized.