NEET-PG 2018 — Community Medicine
12 Previous Year Questions with Answers & Explanations
What is the ratio of incidence of a disease among the exposed to the incidence among non-exposed?
According to WHO classification, severe thinness is defined as a BMI below which value?
Which of the following does not cause hardness of water?
Incidence of a disease is 4 per 1000 of population with duration of 2 years. Calculate the prevalence?
In a screening test for DM out of 1000 population, 90 were positive. When the gold standard test was applied to the entire population, 100 were found to have the disease. Assuming all 90 screening positives were confirmed as true positives by the gold standard, calculate the sensitivity.
Which of the following statements regarding the Factory Act is correct?
Which of the following constitutional articles is not related to children?
The online software used to monitor TB control program under RNTCP is:
The study unit in Ecological study is:
WHO global target for prevention and control of non communicable diseases by 2025 is to decrease the prevalence of raised blood pressure (hypertension) by
NEET-PG 2018 - Community Medicine NEET-PG Practice Questions and MCQs
Question 1: What is the ratio of incidence of a disease among the exposed to the incidence among non-exposed?
- A. Odds ratio
- B. Relative risk (Correct Answer)
- C. Absolute risk
- D. Attributable risk
Explanation: ***Relative risk*** - **Relative risk** (RR) directly compares the **incidence of disease** in an exposed group to the incidence in an unexposed group. - It is used in **cohort studies** and **randomized controlled trials** to quantify the strength of an association between an exposure and an outcome. *Odds ratio* - The **odds ratio** (OR) is a measure of association between an exposure and an outcome in **case-control studies**. - It compares the odds of exposure among cases to the odds of exposure among controls, not directly comparing incidence rates. *Absolute risk* - **Absolute risk** is the **incidence of a disease** in a population, without comparison to another group. - It represents the probability of developing a disease over a specified period. *Attributable risk* - **Attributable risk** (AR) quantifies the amount of disease that can be **attributed to a specific exposure**. - It is the difference in incidence rates between exposed and unexposed groups, not a ratio.
Question 2: According to WHO classification, severe thinness is defined as a BMI below which value?
- A. 18
- B. 14
- C. < 16 (Correct Answer)
- D. 13
Explanation: ***Correct: < 16 kg/m²*** - The WHO classifies **BMI < 16 kg/m²** as **severe thinness (Grade 3 thinness)** - This represents critically low body weight with significant health risks - Values like 12, 13, 14, or 15 all fall into this severe thinness category *18* - BMI **18.5-24.9 kg/m²** is classified as **normal/healthy weight** by WHO - BMI **17.0-18.49 kg/m²** is classified as **mild thinness (Grade 1)** - 18 is not the threshold for severe thinness *14* - 14 kg/m² is **an example of a value** that falls within severe thinness - However, the question asks for the **threshold/cutoff value**, which is **16 kg/m²** - Any BMI below 16 (including 14, 13, 12) indicates severe thinness *13* - Like option 14, this is **a value within** the severe thinness range - The **defining threshold** is **< 16 kg/m²**, not 13 - The question asks for the classification cutoff, not an example value within the range
Question 3: Which of the following does not cause hardness of water?
- A. Calcium bicarbonate
- B. Magnesium bicarbonate
- C. Calcium carbonate (Correct Answer)
- D. Calcium sulphate
Explanation: ***Calcium carbonate*** - Calcium carbonate (CaCO₃) in its **pure solid form has very low solubility** in water (~15 mg/L), making it the least likely of these compounds to directly contribute to water hardness. - While CaCO₃ can react with dissolved CO₂ to form soluble calcium bicarbonate, **pure calcium carbonate itself tends to precipitate out** as scale or sediment rather than remaining dissolved as ions that cause hardness. - This makes it the correct answer as the compound that **does not directly cause hardness** among the options listed. *Calcium bicarbonate* - **Calcium bicarbonate [Ca(HCO₃)₂] is highly soluble** in water and readily dissociates into Ca²⁺ and HCO₃⁻ ions. - This dissolved compound is a **primary cause of temporary hardness** in water, which can be removed by boiling. *Magnesium bicarbonate* - Similar to calcium bicarbonate, **magnesium bicarbonate [Mg(HCO₃)₂] is soluble** in water. - Its presence as dissolved Mg²⁺ ions contributes significantly to **temporary hardness**. *Calcium sulphate* - **Calcium sulphate (CaSO₄) is moderately soluble** in water. - It is a common cause of **permanent hardness** in water, as it cannot be removed by boiling and remains dissolved.
Question 4: Incidence of a disease is 4 per 1000 of population with duration of 2 years. Calculate the prevalence?
- A. 8 per 1000 (Correct Answer)
- B. 4 per 1000
- C. 2 per 1000
- D. 6 per 1000
Explanation: ***8 per 1000*** - Prevalence can be estimated by multiplying the **incidence rate** by the **duration of the disease**. - In this case, 4/1000 (incidence) * 2 years (duration) = **8 per 1000**. *4 per 1000* - This value represents the **incidence** of the disease, which is the rate of new cases, not the total number of existing cases (prevalence). - Prevalence includes both new and existing cases over a specified period. *2 per 1000* - This value is obtained by dividing the incidence by the duration (4/2), which is not the correct formula for calculating prevalence in this context. - Doing so would incorrectly imply a lower disease burden than what is indicated by the incidence and duration. *6 per 1000* - This option is simply the sum of incidence and duration (4+2), which does not represent a valid epidemiological calculation for prevalence. - Prevalence is determined by considering both the rate of new cases and how long individuals typically live with the disease.
Question 5: In a screening test for DM out of 1000 population, 90 were positive. When the gold standard test was applied to the entire population, 100 were found to have the disease. Assuming all 90 screening positives were confirmed as true positives by the gold standard, calculate the sensitivity.
- A. All positives identified by the test assumed as true positives (100%)
- B. True positives divided by total actual positives (90%) (Correct Answer)
- C. Underestimated true positives divided by total actual positives (80%)
- D. Total positives identified by the test divided by total actual positives (90%)
Explanation: ***True positives divided by total actual positives (90%)*** - **Sensitivity** is the proportion of true positives correctly identified by a screening test among all individuals who actually have the disease. It is calculated by (Number of True Positives) / (Total Number of Diseased Individuals). - In this case, 90 people screened positive and were confirmed as **true positives**. The total number of people with the disease (actual positives) is 100. So, sensitivity = 90/100 = **90%**. *Total positives identified by the test divided by total actual positives (90%)* - While this option states the correct percentage (90%), the phrasing "total positives identified by the test" is misleading terminology. In screening test evaluation, this could be confused with all test positives (which would include false positives if they existed). - The correct terminology is "true positives" divided by "total actual positives," not "total positives identified by the test." The distinction is important: true positives are confirmed cases, while test positives might include false positives. *All positives identified by the test assumed as true positives (100%)* - This option incorrectly assumes that because all 90 screening positives were confirmed as true positives, the sensitivity must be 100%. However, sensitivity measures how many of ALL diseased individuals were caught, not just those who screened positive. - There were 100 actual diseased individuals, and only 90 were identified by the screening test; therefore, the sensitivity cannot be 100%. The test missed 10 diseased individuals (false negatives). *Underestimated true positives divided by total actual positives (80%)* - This option presents an arbitrary percentage that does not reflect the given data. There is no information to suggest that the true positives were underestimated or that the calculation would result in 80%. - The actual number of true positives (90) and actual positives (100) directly leads to a sensitivity calculation of 90%, not 80%.
Question 6: Which of the following statements regarding the Factory Act is correct?
- A. Workers can work more than 72 hours per week in factories
- B. The Factory Act allows workers to work more than 82 hours per week
- C. Children under 14 years are not allowed to work in factories (Correct Answer)
- D. Children under 14 years can work in factories if they earn more money
Explanation: ***Children under 14 years are not allowed to work in factories.*** - The Factory Act specifically prohibits the employment of **children below a certain age** to protect them from hazardous working conditions and ensure their development. - This provision is crucial for preventing **child labor** and enforcing fundamental labor rights. *Workers can work more than 72 hours per week in factories* - The Factory Act generally sets limits on working hours, typically around **48 hours per week** with provisions for overtime, but rarely allowing for more than 72 hours under ordinary circumstances. - Excessive working hours without proper rest periods would violate **worker safety** and health regulations. *The Factory Act allows workers to work more than 82 hours per week* - This statement is incorrect as the Factory Act aims to protect workers from **exploitation** and ensure humane working conditions, which includes strict limits on working hours. - Working 82 hours per week would be far beyond the legal limits, leading to **fatigue** and increased risk of accidents. *Children under 14 years can work in factories if they earn more money* - The Factory Act establishes a **minimum age for employment** regardless of potential earnings, prioritizing the child's well-being over financial incentives. - Allowing children under 14 to work, even for higher wages, would undermine **child protection laws** and encourage child labor.
Question 7: Which of the following constitutional articles is not related to children?
- A. 23
- B. 42 (Correct Answer)
- C. 24
- D. 21-A
Explanation: ***Article 42*** - Article 42 of the Indian Constitution deals with **provision for just and humane conditions of work** and **maternity relief**, primarily concerning adult workers, particularly women. - While maternity relief indirectly benefits children by supporting mothers, the article's direct focus is not on children's rights or welfare. *Article 23* - Article 23 prohibits **traffic in human beings and forced labor**, including **begar** and other forms of forced labor. - This article is directly related to children as it safeguards them from exploitation, such as **child trafficking** and forced labor. *Article 21-A* - Article 21-A guarantees the **right to education** for all children between the ages of six and fourteen years. - It mandates that the state shall provide free and compulsory education, making it fundamentally related to children's rights. *Article 24* - Article 24 prohibits the **employment of children below the age of fourteen years** in any factory or mine or engages them in any other hazardous employment. - This article directly protects children from various forms of child labor and is thus related to child welfare.
Question 8: The online software used to monitor TB control program under RNTCP is:
- A. NIRBHAI
- B. NIKSHAY (Correct Answer)
- C. e-DOTS
- D. NISCHAY
Explanation: ***Correct Answer: NIKSHAY*** - **NIKSHAY** is the official **web-based patient management system** for monitoring the TB control program under the **Revised National Tuberculosis Control Programme (RNTCP)**, now known as the National Tuberculosis Elimination Programme (NTEP) - It serves as a comprehensive platform for **real-time case notification, treatment monitoring, and tracking of patient outcomes** - Enables **digital recording** of TB patient details, treatment regimens, and follow-up information across India *Incorrect: NIRBHAI* - This is not a recognized software platform associated with RNTCP or TB control monitoring - No official government health program uses this name for TB surveillance *Incorrect: e-DOTS* - While **DOTS (Directly Observed Treatment, Short-course)** is the core treatment strategy for TB, e-DOTS is not the comprehensive online monitoring software - e-DOTS may refer to electronic recording of DOTS adherence, but **NIKSHAY** is the overarching national platform *Incorrect: NISCHAY* - This is not a recognized software platform for RNTCP monitoring - Does not correspond to any official TB control initiative in India
Question 9: The study unit in Ecological study is:
- A. Case
- B. Population (Correct Answer)
- C. Patient
- D. Community
Explanation: ***Population*** - In an **ecological study**, the primary unit of observation and analysis is a **group or population**, rather than individuals. - Researchers examine disease rates and exposures across different populations or within the same population over time, looking for correlations. *Case* - A **case** refers to an individual with a specific disease or outcome, which is the unit of study in case-control studies. - Ecological studies do not focus on individual cases but rather on aggregate data for groups. *Patient* - A **patient** is an individual under medical care, typically the unit of study in clinical trials or case series. - Ecological studies analyze health patterns at a broader, population level, not at the individual patient level. *Community* - While a community can represent a population, in the context of ecological studies, **population** is the more precise and universally accepted term for the unit of analysis. - The term "community" might imply a smaller or more specific social grouping than the broader "population" often considered in ecological studies.
Question 10: WHO global target for prevention and control of non communicable diseases by 2025 is to decrease the prevalence of raised blood pressure (hypertension) by
- A. 75%
- B. 25% (Correct Answer)
- C. 90%
- D. 55%
Explanation: ***25%*** - The World Health Organization (WHO) set a **global target** to achieve a **25% relative reduction** in the prevalence of **raised blood pressure (hypertension)** by 2025 (compared to 2010 baseline). - This target is part of the **WHO Global Action Plan for NCDs** and the Global Monitoring Framework to combat **non-communicable diseases (NCDs)**. *75%* - A 75% reduction in hypertension prevalence is an **unrealistically ambitious** target given current global health challenges and interventions. - While significant reductions are desired, the evidence-based target set by WHO is a more achievable 25% reduction. *90%* - A 90% reduction is not one of the specifically stated **WHO global targets** for hypertension by 2025. - Such a drastic reduction would require unprecedented public health interventions and is not supported by current evidence. *55%* - 55% is not a recognized **WHO target** for the prevention and control of hypertension by 2025. - The established global target from the WHO NCD Global Monitoring Framework specifically focuses on a **25% relative reduction**.