Which graphical representation is best suited for depicting continuous quantitative data?
Berksonian bias is a type of ?
What is the term for the time between infection and maximum infectivity?
Which cancer type has the most effective screening procedure?
Which vaccine is used to prevent cholera?
What is the concentration of type 3 virus in the trivalent oral polio vaccine?
What is the common adulterant found in black pepper?
What is the target age group for the Integrated Management of Neonatal and Childhood Illnesses (IMNCI)?
What does perinatal mortality include?
What does the black color signify in the triage system?
NEET-PG 2012 - Community Medicine NEET-PG Practice Questions and MCQs
Question 51: Which graphical representation is best suited for depicting continuous quantitative data?
- A. Bar diagram
- B. Pie chart
- C. Histogram (Correct Answer)
- D. Pictogram
Explanation: **Histogram** - A **histogram** is specifically designed for depicting the distribution of **continuous quantitative data** by dividing the data into bins and showing the frequency of data points within each bin. - The bars in a histogram are adjacent, indicating the continuous nature of the data and representing ranges of values. *Bar diagram* - A **bar diagram** (or bar chart) is typically used for comparing **discrete categories** or displaying changes over time for categorical data. - The bars in a bar diagram are usually separated, emphasizing distinct categories rather than continuous ranges. *Pie chart* - A **pie chart** is used to show the **proportions of a whole**, representing parts of a composition for categorical data. - It is not suitable for continuous data as it provides no information about the distribution or frequency across a range of values. *Pictogram* - A **pictogram** uses images or icons to represent data, making it visually engaging, but it is generally used for **simple comparisons of discrete or categorical data**. - It lacks the precision and detail required to accurately depict the distribution or frequency of continuous quantitative data.
Question 52: Berksonian bias is a type of ?
- A. Selection bias (Correct Answer)
- B. Information bias
- C. Interviewer bias
- D. Recall bias
Explanation: ***Selection bias*** - **Berkson's bias** is a form of **selection bias** that arises in studies conducted using hospital data. - It occurs when the probability of admission to a hospital or inclusion in a study is conditional on both exposure and disease status, leading to a **flawed association** between them. *Interviewer bias* - **Interviewer bias** is a type of **information bias** where the interviewer's expectations or knowledge about the study or participants influence the way information is sought or recorded. - This typically affects the **data collection process** and not the selection of participants. *Information bias* - **Information bias** is a broad category of biases that arise from **systematic errors in measurement** or classification of exposure or disease. - While Berkson's bias can lead to misinformation, its root cause is in how subjects are selected, not how data on those subjects is collected after selection. *Recall bias* - **Recall bias** is a type of **information bias** where there are systematic differences in the way participants **recall past events or exposures**. - It is particularly common in **case-control studies** where individuals with a disease may remember exposures differently than healthy controls.
Question 53: What is the term for the time between infection and maximum infectivity?
- A. Communicable period
- B. Generation time (Correct Answer)
- C. Incubation period
- D. Serial interval
Explanation: ***Generation time*** - This is the **time interval** between receipt of infection by a host and the moment of **maximum infectivity** of that same host. - It is a crucial parameter in epidemiology for understanding **disease transmission dynamics** and the speed at which an epidemic can spread. *Incubation period* - This refers to the time from **exposure to an infectious agent** until the **onset of symptoms**. - It does not directly account for the timing of viral shedding or peak infectivity. *Serial interval* - This is the time between **symptom onset in a primary case** and **symptom onset in a secondary case** it infects. - While related to transmission, it focuses on symptomatic presentation rather than peak infectivity. *Communicable period* - This is the time during which an infected individual is **capable of transmitting** the infectious agent to others. - It represents the entire duration of potential transmission, not specifically the peak infectivity.
Question 54: Which cancer type has the most effective screening procedure?
- A. Prostate Cancer
- B. Colon Cancer
- C. Cervical Cancer (Correct Answer)
- D. Gastric Cancer
Explanation: ***Cervical Cancer*** - **Pap smear and HPV testing** represent the most effective cancer screening program, with proven reduction of **>70% in cervical cancer incidence and mortality**. - Screening detects **pre-cancerous lesions (CIN)** during the long latent period, allowing for effective intervention before cancer develops. - Well-established guidelines with high sensitivity, specificity, and cost-effectiveness make it a **public health success story**. - Particularly relevant in Indian context where cervical cancer burden is high and screening programs are being expanded. *Colon Cancer* - **Colonoscopy** and **fecal occult blood testing (FOBT)** are highly effective, allowing direct visualization and removal of precancerous polyps. - While very effective with proven mortality reduction, screening uptake is lower and the procedure is more invasive than cervical cancer screening. - Effectiveness is comparable but cervical cancer screening has achieved greater population-level impact historically. *Prostate Cancer* - Screening with **PSA (prostate-specific antigen) testing** and **digital rectal exam (DRE)** is controversial due to potential for **overdiagnosis and overtreatment** of indolent cancers. - Impact on overall mortality reduction is debated, and it doesn't prevent cancer through detection of precancerous lesions like cervical/colon cancer screening. *Gastric Cancer* - **Gastric cancer screening** is not routinely recommended in most countries including India due to lower prevalence and lack of a highly effective, non-invasive screening method. - **Endoscopy** can detect gastric cancer but is typically performed in symptomatic individuals or high-risk populations (e.g., Japan, Korea), not as a general population screening tool.
Question 55: Which vaccine is used to prevent cholera?
- A. CVD 103-HgR
- B. Ty21 A
- C. WC-rBS (Correct Answer)
- D. None of the options
Explanation: ***WC-rBS*** * **WC-rBS** stands for **whole-cell, recombinant B subunit** vaccine, also known as **Dukoral**. * It is an **oral inactivated vaccine** containing killed *Vibrio cholerae* O1 bacteria and the recombinant B subunit of the cholera toxin, providing immunity against cholera. * **WC-rBS is the WHO-prequalified cholera vaccine** widely used in India and recommended for travellers and in epidemic settings. * It provides protection against both O1 and O139 serogroups and offers some cross-protection against ETEC (enterotoxigenic *E. coli*). *CVD 103-HgR* * **CVD 103-HgR** (commercially known as **Vaxchora**) is an **oral live-attenuated cholera vaccine** approved by the FDA. * It is a genetically modified *Vibrio cholerae* O1 Inaba strain with deleted cholera toxin genes. * While this is also a cholera vaccine, **it is primarily used in the United States** and is not the standard vaccine used in India or recommended by WHO for mass vaccination campaigns. * In the Indian context and for NEET-PG examinations, **WC-rBS (Dukoral) is the recognized cholera vaccine**. *Ty21a* * **Ty21a** is an **oral live-attenuated vaccine** used to prevent **typhoid fever**. * It is specifically designed to target *Salmonella Typhi* bacteria, not *Vibrio cholerae*. *None of the options* * This option is incorrect because WC-rBS is the well-established and WHO-recommended vaccine for the prevention of cholera in the Indian context.
Question 56: What is the concentration of type 3 virus in the trivalent oral polio vaccine?
- A. 400,000 TCID 50
- B. 100,000 TCID 50
- C. 300,000 TCID 50
- D. 600,000 TCID 50 (Correct Answer)
Explanation: ***600,000 TCID 50*** - The **trivalent oral polio vaccine (tOPV)** traditionally contained specific concentrations of each serotype: **type 1 (1,000,000 TCID50/dose)**, **type 2 (100,000 TCID50/dose)**, and **type 3 (600,000 TCID50/dose)**. - Type 3 poliovirus requires a **higher concentration (600,000 TCID50)** compared to type 2 to achieve adequate immunogenicity and protection. - The **World Health Organization (WHO)** established these specific formulations for tOPV to ensure optimal efficacy and safety for each serotype. *100,000 TCID 50* - This is the concentration of **type 2 poliovirus** in tOPV, not type 3. - Due to the **global eradication of wild poliovirus type 2** by 2015, tOPV was replaced with bivalent OPV (bOPV) containing only types 1 and 3 in routine immunization programs. *400,000 TCID 50* - This concentration does not correspond to any standard poliovirus serotype in the traditional trivalent oral polio vaccine. - This value falls between type 2 (100,000) and type 3 (600,000) concentrations but is not used. *300,000 TCID 50* - This concentration is not the standard for any poliovirus serotype in the traditional trivalent oral polio vaccine. - Each serotype has a **distinct, empirically determined concentration** to achieve optimal immunity while minimizing adverse effects.
Question 57: What is the common adulterant found in black pepper?
- A. Khesari dal
- B. Fine sand
- C. None of the options
- D. Dried papaya seeds (Correct Answer)
Explanation: ***Dried papaya seeds*** - **Dried papaya seeds** are a common adulterant in black pepper due to their similar size, shape, and color, making them difficult to distinguish visually. - Adulteration with papaya seeds is often done to increase the bulk and weight of the black pepper product, thereby reducing production costs. *Khesari dal* - **Khesari dal (Lathyrus sativus)** is a type of lentil known for causing **lathyrism**, a neurotoxic disorder, but it is not typically used to adulterate black pepper. - Its appearance and texture are distinctly different from black pepper, making it an unsuitable adulterant. *Fine sand* - **Fine sand** can be an adulterant in spices, but it is more commonly found in powdered spices like chilli powder or turmeric due to its fine particle size. - While it adds weight, its presence in whole black pepper would be easily detectable due to its abrasive texture and grittiness. *None of the options* - This option is incorrect because **dried papaya seeds** are a well-documented and common adulterant in black pepper. - The similarities in appearance make it a frequent choice for unscrupulous suppliers.
Question 58: What is the target age group for the Integrated Management of Neonatal and Childhood Illnesses (IMNCI)?
- A. Up to 5 years (Correct Answer)
- B. Up to 10 years
- C. Up to 15 years
- D. Up to 20 years
Explanation: ***Up to 5 years*** - The **Integrated Management of Neonatal and Childhood Illnesses (IMNCI)** program focuses on children from **birth up to five years of age**. - This age range was chosen because it represents the period with the highest rates of **childhood morbidity and mortality** due to common preventable and treatable illnesses. *Up to 10 years* - While children up to 10 years might experience various illnesses, the primary focus of **IMNCI** is specifically on the **under-five age group**. - Expanding the program to this age group would require different diagnostic and management protocols for conditions less prevalent in younger children. *Up to 15 years* - The **IMNCI strategy** is designed for the specific health needs and common illnesses found in infants and young children, not adolescents. - Health challenges for children aged 5-15 years often involve different conditions and require distinct healthcare approaches. *Up to 20 years* - Individuals up to 20 years fall into adolescent and young adult health categories, which are outside the scope of the **IMNCI program**. - Their health needs are significantly different from those of neonates and young children targeted by IMNCI.
Question 59: What does perinatal mortality include?
- A. Deaths after 28 weeks of gestation
- B. Deaths within the first 7 days after birth
- C. From the period of viability
- D. Both late fetal deaths and early neonatal deaths (Correct Answer)
Explanation: ***Both late fetal deaths and early neonatal deaths*** - Perinatal mortality encompasses deaths occurring both in the **late fetal period** (typically after 20-22 weeks of gestation, or commonly defined as 28 weeks or more) and during the **early neonatal period** (the first 7 days of life). - This broad definition helps to capture mortality related to conditions around the time of birth, including those stemming from **pregnancy complications**, labor, delivery, and immediate postnatal adaptation. *Deaths after 28 weeks of gestation* - This describes **late fetal deaths** (stillbirths) but does not include deaths that occur after birth, thus only covering a part of perinatal mortality. - Perinatal mortality is a broader measure that combines both stillbirths and early infant deaths. *Deaths within the first 7 days after birth* - This specifically defines **early neonatal deaths**, which are a component of perinatal mortality, but it excludes fetal deaths. - Perinatal mortality aims to assess factors impacting survival around the time of birth, both before and immediately after. *From the period of viability* - The period of viability refers to when a fetus can survive outside the uterus, which varies (often cited as 20-24 weeks), and would include very premature fetuses, but it isn't an explicit definition of perinatal mortality itself. - This term describes when a fetus is considered potentially viable but does not define the specific timeframe or types of deaths included in perinatal mortality.
Question 60: What does the black color signify in the triage system?
- A. Deceased (Correct Answer)
- B. Transfer to hospital
- C. Immediate treatment required
- D. Low priority treatment
Explanation: ***Correct: Deceased (Black Tag)*** - In a **mass casualty incident (MCI)**, the color black in the triage system signifies that an individual is **deceased** or has injuries so severe that survival is unlikely given the available resources. - Triage efforts focus on those with a higher chance of survival, and time and resources are not allocated for resuscitation of black-tagged individuals. *Incorrect: Transfer to hospital* - This is not a color classification but rather an action taken after a patient has been triaged, typically for those with **yellow** or **red** tags. - The color tags themselves denote the **urgency of medical intervention**, not the destination. *Incorrect: Immediate treatment required* - This status is typically represented by a **red tag**, indicating a patient with life-threatening injuries who requires immediate intervention. - Individuals with a red tag have a high priority for rapid medical treatment and transport. *Incorrect: Low priority treatment* - This status is usually represented by a **green tag**, indicating patients with minor injuries who can wait for treatment. - These individuals are often referred to as "walking wounded" and do not require immediate medical attention.