NEET-PG 2025 — Community Medicine

Q: A diabetic patient with COVID-19 dies in the hospital. Which type of surveillance does this death report fall under?

Passive surveillance. ***Passive surveillance*** - This type involves health facilities (like hospitals) routinely sending reports of diseases or deaths to public health authorities without active prompting or investigation from the authorities. - The hospital staff, having recorded the death, is responsible for initiating the report, making this a classic example of **passive case reporting**. *Active surveillance* - This requires public health staff to **actively seek out cases**, often by visiting healthcare facilities, reviewing records, or interviewing healthcare providers and patients. - It is typically more resource-intensive and used for specific **outbreak investigations** or diseases targeted for elimination. *Sentinel surveillance* - This system relies on a **pre-selected, limited network** of reporting sites (e.g., specific hospitals or clinics) to collect high-quality data on specific diseases or conditions. - It is used to monitor trends when comprehensive reporting across all facilities is impractical, often used for conditions like **Influenza-like Illness (ILI)**. *Syndromic surveillance* - This involves the early detection of potential outbreaks by collecting and analyzing pre-diagnostic health data based on **clusters of symptoms (syndromes)**—like chief complaints in the Emergency Department. - It focuses on nonspecific indicators (e.g., fever and cough) for timely detection, primarily used for **bioterrorism preparedness** or rapid onset epidemics. [Practice more Community Medicine PYQs on OnCourse]

Q: An urban city has a population of 70,00,000, with 30 % residing in slum areas. According to NUHM (National Urban Health Mission) norms, how many Urban Primary Health Centres (UPHCs) are required for the slum population?

42. ***Option: 42 (Correct Answer)*** - The slum population is calculated as 30% of 70,00,000, which equals **21,00,000** (2.1 million). - The **NUHM norm** mandates one Urban Primary Health Centre (UPHC) for a population of **50,000** in urban slum areas. - Required UPHCs = 21,00,000 ÷ 50,000 = **42 UPHCs**. *Option: 22 (Incorrect)* - This figure would imply a required population coverage of approximately **1 UPHC per 95,455** people (21,00,000 ÷ 22 ≈ 95,455). - This significantly exceeds the threshold set by the NUHM for vulnerable slum populations (50,000). - This calculation represents a major **under-provision** of primary healthcare infrastructure contrary to public health guidelines for urban poor. *Option: 32 (Incorrect)* - This number would result from using a population norm of about **1 UPHC per 65,625** people (21,00,000 ÷ 32 ≈ 65,625). - This is higher than the standard **50,000** norm for UPHCs in slums. - Using this higher figure would reduce the accessibility and availability of health services required for high-density **slum populations**. *Option: 52 (Incorrect)* - This calculation uses the **lower limit** of the NUHM range: **1 UPHC per 40,000** population (21,00,000 ÷ 40,000 = 52.5 ≈ 52). - While the NUHM range is 40,000-50,000, the standard practice uses **50,000** as the coverage target (resulting in **42 UPHCs**). - Using 40,000 would provide more facilities but the standard norm for calculation purposes is 50,000. [Practice more Community Medicine PYQs on OnCourse]

Q: Which mosquito larva has no siphon and rests parallel to the water surface?

Anopheles. ***Anopheles*** - **Anopheles** larvae lack a **siphon** (breathing tube) and breathe through spiracles located on the dorsal surface of the abdomen. - This absence of a siphon causes them to rest **parallel** to the water surface, which is a key identifying feature for species differentiation. *Aedes* - **Aedes** larvae possess a **siphon**, which is relatively shorter and stouter compared to *Culex*. - They hang down from the water surface at an angle, utilizing the siphon for air intake, not lying parallel to the surface. *Culex* - **Culex** larvae possess a long, distinct **siphon** (breathing tube) at the posterior end of the abdomen. - Due to the siphon, they rest at an **angle** (typically 45-60 degrees) to the water surface for breathing. *Mansonia* - **Mansonia** larvae have a modified, sharp **siphon** used to pierce the submerged **stems of aquatic plants** for oxygen extraction. - They remain attached to these plants underwater and do not float on or rest parallel to the water surface. [Practice more Community Medicine PYQs on OnCourse]

Q: In a district-level survey, the introduction of breast cancer screening showed an increased 5-year survival rate, but autopsy data revealed no change in mortality. What type of bias does this represent?

Lead time bias. **Correct: Lead time bias** - Screening detects the disease at an earlier, pre-symptomatic stage (the **lead time**), which falsely lengthens the measured survival duration (from diagnosis to death) - The increased 5-year survival rate is an artifact of earlier diagnosis rather than improved treatment - The unchanged mortality (autopsy data) confirms that the **time of death was not actually postponed** by the screening—patients simply lived with the diagnosis longer *Incorrect: Survival bias* - Also known as **prevalence-incidence bias**, this occurs when only long-term survivors of a disease are selected for a study, causing an overestimation of prognosis - It does not specifically describe the phenomenon where starting the survival clock sooner (via screening) inflates the apparent survival without affecting the ultimate outcome *Incorrect: Berksonian bias* - This is a type of **selection bias** observed in hospital-based studies, where both the exposure and disease independently increase the likelihood of **hospital admission** - This leads to an unrepresentative control group in case-control studies - Not related to the screening-survival time relationship *Incorrect: Detection bias* - A form of **information bias** where systematic differences in how thoroughly different groups are monitored leads to higher diagnosis rates in the more closely watched group - While screening involves detection, the specific error of early diagnosis shifting the survival start time without changing actual mortality is precisely **lead time bias**, not detection bias [Practice more Community Medicine PYQs on OnCourse]

Q: In the "De facto" method of census data collection, information is collected based on which of the following?

Location at the time of enumeration. ***Location at the time of enumeration*** - The **De facto** method (or Present-in-Area method) counts people based on where they are physically present at the specific time of the census enumeration, irrespective of their usual residence. - This method is simple, avoids double counting among travelers, but may miss people who were away from their usual residence and were not enumerated elsewhere (e.g., homeless or temporary workers). *Place of birth* - Place of birth is a demographic characteristic collected during the census to understand migration patterns, but it is not the principle used for physical counting and location. - Data based on place of birth is used to analyze demographic factors like **lifetime migration** and does not determine inclusion in the count itself. *Usual place of residence* - This approach is known as the **De jure** method (or Permanent Residence method), which counts individuals based on their usual or legal place of residence. - The **De jure method** is often preferred for calculating essential demographic statistics like birth rates and death rates, as it provides a stable population base. *Place of employment* - The place of employment is an economic characteristic used to determine the **working population** and economic activity, not the method used for the population count itself. - This information helps in planning for infrastructure and labor force needs but is secondary to the primary counting methodology. [Practice more Community Medicine PYQs on OnCourse]

15 Previous Year Questions with Answers & Explanations

Questions

A diabetic patient with COVID-19 dies in the hospital. Which type of surveillance does this death report fall under?

An urban city has a population of 70,00,000, with 30 % residing in slum areas. According to NUHM (National Urban Health Mission) norms, how many Urban Primary Health Centres (UPHCs) are required for the slum population?

Which mosquito larva has no siphon and rests parallel to the water surface?

In a district-level survey, the introduction of breast cancer screening showed an increased 5-year survival rate, but autopsy data revealed no change in mortality. What type of bias does this represent?

In the "De facto" method of census data collection, information is collected based on which of the following?

During a Health Mela organized by a medical college, the Nalgonda technique for water purification was demonstrated. Which two chemicals are used in this technique?

A 20-year-old resident of Andhra Pradesh presents with outward bending of the lower limbs and signs of osteoporosis. His diet mainly consists of rice and jowar roti. What should not be done in the management of this patient?

A study is conducted to compare the mean hemoglobin (Hb) levels between two independent groups. Which statistical test is most appropriate?

A 3-year-old child presents with difficulty in walking, bowing of legs, is underweight, and has minimal sun exposure. Which of the following government schemes addresses nutritional deficiencies in children under 6 years of age?

Q10

Under the Weekly Iron and Folic Acid Supplementation (WIFS) scheme, what is the composition of IFA tablets given to children aged 10-19 years?

NEET-PG 2025 - Community Medicine NEET-PG Practice Questions and MCQs

Question 1: A diabetic patient with COVID-19 dies in the hospital. Which type of surveillance does this death report fall under?

A. Sentinel surveillance
B. Syndromic surveillance
C. Passive surveillance (Correct Answer)
D. Active surveillance

Explanation: ***Passive surveillance*** - This type involves health facilities (like hospitals) routinely sending reports of diseases or deaths to public health authorities without active prompting or investigation from the authorities. - The hospital staff, having recorded the death, is responsible for initiating the report, making this a classic example of **passive case reporting**. *Active surveillance* - This requires public health staff to **actively seek out cases**, often by visiting healthcare facilities, reviewing records, or interviewing healthcare providers and patients. - It is typically more resource-intensive and used for specific **outbreak investigations** or diseases targeted for elimination. *Sentinel surveillance* - This system relies on a **pre-selected, limited network** of reporting sites (e.g., specific hospitals or clinics) to collect high-quality data on specific diseases or conditions. - It is used to monitor trends when comprehensive reporting across all facilities is impractical, often used for conditions like **Influenza-like Illness (ILI)**. *Syndromic surveillance* - This involves the early detection of potential outbreaks by collecting and analyzing pre-diagnostic health data based on **clusters of symptoms (syndromes)**—like chief complaints in the Emergency Department. - It focuses on nonspecific indicators (e.g., fever and cough) for timely detection, primarily used for **bioterrorism preparedness** or rapid onset epidemics.

Question 2: An urban city has a population of 70,00,000, with 30 % residing in slum areas. According to NUHM (National Urban Health Mission) norms, how many Urban Primary Health Centres (UPHCs) are required for the slum population?

A. 42 (Correct Answer)
B. 52
C. 22
D. 32

Explanation: ***Option: 42 (Correct Answer)*** - The slum population is calculated as 30% of 70,00,000, which equals **21,00,000** (2.1 million). - The **NUHM norm** mandates one Urban Primary Health Centre (UPHC) for a population of **50,000** in urban slum areas. - Required UPHCs = 21,00,000 ÷ 50,000 = **42 UPHCs**. *Option: 22 (Incorrect)* - This figure would imply a required population coverage of approximately **1 UPHC per 95,455** people (21,00,000 ÷ 22 ≈ 95,455). - This significantly exceeds the threshold set by the NUHM for vulnerable slum populations (50,000). - This calculation represents a major **under-provision** of primary healthcare infrastructure contrary to public health guidelines for urban poor. *Option: 32 (Incorrect)* - This number would result from using a population norm of about **1 UPHC per 65,625** people (21,00,000 ÷ 32 ≈ 65,625). - This is higher than the standard **50,000** norm for UPHCs in slums. - Using this higher figure would reduce the accessibility and availability of health services required for high-density **slum populations**. *Option: 52 (Incorrect)* - This calculation uses the **lower limit** of the NUHM range: **1 UPHC per 40,000** population (21,00,000 ÷ 40,000 = 52.5 ≈ 52). - While the NUHM range is 40,000-50,000, the standard practice uses **50,000** as the coverage target (resulting in **42 UPHCs**). - Using 40,000 would provide more facilities but the standard norm for calculation purposes is 50,000.

Question 3: Which mosquito larva has no siphon and rests parallel to the water surface?

A. Aedes
B. Mansonia
C. Anopheles (Correct Answer)
D. Culex

Explanation: ***Anopheles*** - **Anopheles** larvae lack a **siphon** (breathing tube) and breathe through spiracles located on the dorsal surface of the abdomen. - This absence of a siphon causes them to rest **parallel** to the water surface, which is a key identifying feature for species differentiation. *Aedes* - **Aedes** larvae possess a **siphon**, which is relatively shorter and stouter compared to *Culex*. - They hang down from the water surface at an angle, utilizing the siphon for air intake, not lying parallel to the surface. *Culex* - **Culex** larvae possess a long, distinct **siphon** (breathing tube) at the posterior end of the abdomen. - Due to the siphon, they rest at an **angle** (typically 45-60 degrees) to the water surface for breathing. *Mansonia* - **Mansonia** larvae have a modified, sharp **siphon** used to pierce the submerged **stems of aquatic plants** for oxygen extraction. - They remain attached to these plants underwater and do not float on or rest parallel to the water surface.

Question 4: In a district-level survey, the introduction of breast cancer screening showed an increased 5-year survival rate, but autopsy data revealed no change in mortality. What type of bias does this represent?

A. Berksonian bias
B. Detection bias
C. Survival bias
D. Lead time bias (Correct Answer)

Explanation: **Correct: Lead time bias** - Screening detects the disease at an earlier, pre-symptomatic stage (the **lead time**), which falsely lengthens the measured survival duration (from diagnosis to death) - The increased 5-year survival rate is an artifact of earlier diagnosis rather than improved treatment - The unchanged mortality (autopsy data) confirms that the **time of death was not actually postponed** by the screening—patients simply lived with the diagnosis longer *Incorrect: Survival bias* - Also known as **prevalence-incidence bias**, this occurs when only long-term survivors of a disease are selected for a study, causing an overestimation of prognosis - It does not specifically describe the phenomenon where starting the survival clock sooner (via screening) inflates the apparent survival without affecting the ultimate outcome *Incorrect: Berksonian bias* - This is a type of **selection bias** observed in hospital-based studies, where both the exposure and disease independently increase the likelihood of **hospital admission** - This leads to an unrepresentative control group in case-control studies - Not related to the screening-survival time relationship *Incorrect: Detection bias* - A form of **information bias** where systematic differences in how thoroughly different groups are monitored leads to higher diagnosis rates in the more closely watched group - While screening involves detection, the specific error of early diagnosis shifting the survival start time without changing actual mortality is precisely **lead time bias**, not detection bias

Question 5: In the "De facto" method of census data collection, information is collected based on which of the following?

A. Place of birth
B. Usual place of residence
C. Location at the time of enumeration (Correct Answer)
D. Place of employment

Explanation: ***Location at the time of enumeration*** - The **De facto** method (or Present-in-Area method) counts people based on where they are physically present at the specific time of the census enumeration, irrespective of their usual residence. - This method is simple, avoids double counting among travelers, but may miss people who were away from their usual residence and were not enumerated elsewhere (e.g., homeless or temporary workers). *Place of birth* - Place of birth is a demographic characteristic collected during the census to understand migration patterns, but it is not the principle used for physical counting and location. - Data based on place of birth is used to analyze demographic factors like **lifetime migration** and does not determine inclusion in the count itself. *Usual place of residence* - This approach is known as the **De jure** method (or Permanent Residence method), which counts individuals based on their usual or legal place of residence. - The **De jure method** is often preferred for calculating essential demographic statistics like birth rates and death rates, as it provides a stable population base. *Place of employment* - The place of employment is an economic characteristic used to determine the **working population** and economic activity, not the method used for the population count itself. - This information helps in planning for infrastructure and labor force needs but is secondary to the primary counting methodology.

Question 6: During a Health Mela organized by a medical college, the Nalgonda technique for water purification was demonstrated. Which two chemicals are used in this technique?

A. Alum and Gypsum
B. Alum and Lime (Correct Answer)
C. Alum and Charcoal
D. Charcoal and Lime

Explanation: ***Alum and Lime*** - The **Nalgonda technique** is a simple and cost-effective method for defluoridation of water, primarily using **alum** (aluminum sulfate) and **lime** (calcium hydroxide). - The process involves mixing water with these chemicals, quick mixing, slow stirring, sedimentation, and filtration, resulting in the removal of **fluorides** through precipitation and adsorption. *Alum and Gypsum* - **Gypsum** (calcium sulfate) is not a primary component of the standard Nalgonda technique for defluoridation. - While calcium compounds are involved (lime), gypsum is more commonly encountered in soil stabilization or as a source of calcium/sulfur. *Alum and Charcoal* - While **activated charcoal** is used in water purification for removing organic contaminants, taste, and odor, it is not a required material in the specific **Nalgonda defluoridation process**. - The Nalgonda method relies on the precipitation of **aluminum hydroxyfluoride** complex using alum and lime. *Charcoal and Lime* - **Charcoal** is not the specified adsorbent agent used in this technique; its main function is flavor and odor removal, not binding fluoride effectively in this process. - The technique requires the coagulant properties of **alum** (aluminum salt) to facilitate the precipitation reaction with fluoride ions.

Question 7: A 20-year-old resident of Andhra Pradesh presents with outward bending of the lower limbs and signs of osteoporosis. His diet mainly consists of rice and jowar roti. What should not be done in the management of this patient?

A. Provision of running surface water for drinking
B. Fluoride supplementation (Correct Answer)
C. Change the water source
D. Add lime and alum to drinking water

Explanation: ***Fluoride supplementation*** - The clinical presentation (outward bending of lower limbs, osteoporosis) in an endemic area like Andhra Pradesh strongly suggests **Skeletal Fluorosis**, likely from high fluoride levels in drinking water. - **Fluoride supplementation** would exacerbate the condition by increasing the total fluoride body burden, leading to worsening of the bone deformities and pain. *Provision of running surface water for drinking* - This is a recommended management step as **surface water** typically has much lower concentrations of **fluoride** compared to deep borehole water, thereby reducing intake. - This action directly targets the removal of the primary source of excess fluoride ingestion. *Change the water source* - This is a key public health measure to reduce fluoride exposure by replacing the current high-fluoride source with a source known to have safe levels (less than 1.5 ppm, ideally less than 1.0 ppm). - Reducing the long-term consumption of high-fluoride water is essential to halt the progression of **skeletal fluorosis**. *Add lime and alum to drinking water* - Adding **lime (calcium oxide)** and **alum (aluminum sulfate)** is a recognized defluoridation technique (especially the Nalgonda technique). - This method effectively precipitates and removes excess **fluoride** from the water, making it a viable public health intervention.

Question 8: A study is conducted to compare the mean hemoglobin (Hb) levels between two independent groups. Which statistical test is most appropriate?

A. Paired t-test
B. Chi-square test
C. Unpaired t-test (Correct Answer)
D. ANOVA

Explanation: ***Unpaired t-test*** - This test is specifically used to compare the **means** of a continuous outcome variable (like hemoglobin level) between **two independent, unrelated groups**. - It is based on the assumption that the data is normally distributed and variances are equal (though modifications exist if variances are unequal, known as Welch's t-test). *Paired t-test* - The paired t-test is used when the data comes from **dependent** or **related groups**, such as measuring the same individuals before and after an intervention (pre-post study). - Since the question specifies two **independent** groups, this test is incorrect. *Chi-square test* - This test is used to analyze the association or difference between **two or more categorical variables** (e.g., comparing proportions or frequencies in nominal data). - It is unsuitable for comparing the **mean** of a **continuous variable** like Hb levels. *ANOVA* - Analysis of Variance (ANOVA) is used to compare the **means** of a continuous variable among **three or more independent groups**. - Since the study involves only **two groups**, the unpaired t-test is the simpler and more conventional choice, although ANOVA yields the same result when reduced to two groups.

Question 9: A 3-year-old child presents with difficulty in walking, bowing of legs, is underweight, and has minimal sun exposure. Which of the following government schemes addresses nutritional deficiencies in children under 6 years of age?

A. Mid-Day Meal Scheme
B. Integrated Child Development Services (ICDS) (Correct Answer)
C. Anemia Mukt Bharat
D. National Nutritional Deficiency Control Programme

Explanation: ***Integrated Child Development Services (ICDS)*** - ICDS is a comprehensive scheme launched in 1975 to address nutritional and health needs of children **under 6 years** and pregnant/lactating women - Provides a package of services including **supplementary nutrition, health check-ups, immunization, and non-formal preschool education** - Directly addresses nutritional status of children in this age group through Anganwadi centers - The clinical scenario (rickets with malnutrition) represents the target population for ICDS interventions *Mid-Day Meal Scheme* - Targets children in **primary and upper primary schools (age 6-14 years)**, not children under 6 - Main objectives are to enhance enrollment, retention, and school attendance while improving nutrition - Does not cover the 3-year-old child in the scenario *Anemia Mukt Bharat* - Specific strategy focused on controlling and eliminating **iron deficiency anemia** across different population groups - Not a comprehensive scheme for all nutritional deficiencies in children under 6 - Utilizes targeted interventions like iron and folic acid supplementation (WIFS programs) *National Nutritional Deficiency Control Programme* - This is a descriptive term, not an official single program name - India has various disease-specific control programs (e.g., National Iodine Deficiency Disorder Control Programme), but no overarching program with this exact name - ICDS remains the primary umbrella scheme for nutritional deficiencies in children under 6

Question 10: Under the Weekly Iron and Folic Acid Supplementation (WIFS) scheme, what is the composition of IFA tablets given to children aged 10-19 years?

A. 100 mg elemental iron + 100 µg folic acid
B. 60 mg elemental iron + 500 µg folic acid (Correct Answer)
C. 60 mg elemental iron + 100 µg folic acid
D. 100 mg elemental iron + 500 µg folic acid

Explanation: ***Correct: 60 mg elemental iron + 500 µg folic acid*** - This tablet composition is specifically designated for the **Weekly Iron and Folic Acid Supplementation (WIFS)** program, targeting schoolchildren and adolescents (10-19 years). - The tablets provided for this age group are characteristically **blue** in color. - Given **once weekly** as prophylactic supplementation to prevent anemia in this vulnerable age group. *Incorrect: 60 mg elemental iron + 100 µg folic acid* - This composition (often a pink tablet) is typically used for the treatment of **anemia in children** aged 6 months to 5 years under the National Iron Plus Initiative (NIPI). - The dose of **folic acid (100 µg)** is insufficient for the adolescent WIFS scheme. *Incorrect: 100 mg elemental iron + 500 µg folic acid* - This is the standard dose of IFA recommended for routine supplementation in **pregnant women** starting from the second trimester. - The **red tablet** contains both higher elemental iron (**100 mg**) and appropriate folic acid (500 µg) for pregnancy needs. - The iron content is significantly higher than the **60 mg** prescribed for weekly adolescent prophylaxis. *Incorrect: 100 mg elemental iron + 100 µg folic acid* - This particular combination does not align with the standardized dosage protocols under the NIPI/WIFS guidelines. - Neither the iron content (**100 mg** - too high) nor the folic acid content (**100 µg** - too low) matches the adolescent WIFS requirements.