Community Medicine
8 questionsSpecificity of a test is =
With reference to historical cohort study, which of the following statements is not correct?
Iodine can be used for the disinfection of which of the following? 1. Water 2. Faeces 3. Urine 4. Skin Select the correct answer using the code given below:
Consider the following: 1. Standard deviation 2. Range 3. Mode 4. Median Among the above, which is/are the measure/measures of dispersion?
Which of the following diseases has man as an incidental host with ‘Pig → Mosquito → Pig’ as the basic cycle of transmission?
A screening programme for school children was undertaken with the following results: 1. 30% boys and 60% girls were found to be anemic 2. 50% children had history of passing worms in stool 3. 10% children had poor vision 4. 5% children had enlarged tonsils In this context, which of the following is not an appropriate follow up activity?
Sullivan’s index is an indicator of:
Which one of the following mosquitoes is responsible for transmitting Japanese encephalitis?
UPSC-CMS 2014 - Community Medicine UPSC-CMS Practice Questions and MCQs
Question 101: Specificity of a test is =
- A. (True positives X 100) / (True negatives + False positives) %
- B. (True positives X 100) / (True positives + False negatives) %
- C. (True negatives X 100) / (True negatives + False positives) % (Correct Answer)
- D. (True negatives X 100) / (True positives + True negatives) %
Explanation: ***(True negatives X 100) / (True negatives + False positives) %*** - **Specificity** measures the proportion of **true negatives** correctly identified by the test among all individuals who do not have the disease. - It reflects the test's ability to **correctly identify healthy individuals** and avoid **false positives**. * (True positives X 100) / (True negatives + False positives) %* - This formula is incorrect for specificity, as it uses **true positives** in the numerator which is characteristic of **sensitivity**, not specificity. - The denominator includes true negatives but incorrectly adds **false positives**, which would be appropriate for the total number of individuals without the disease. * (True positives X 100) / (True positives + False negatives) %* - This formula represents the **sensitivity** of a test, not its specificity. - **Sensitivity** measures the proportion of **true positives** correctly identified by the test among all individuals who actually have the disease. * (True negatives X 100) / (True positives + True negatives) %* - This formula incorrectly includes **true positives** in the denominator, which is not relevant for calculating specificity. - The denominator should represent all truly negative cases (true negatives + false positives).
Question 102: With reference to historical cohort study, which of the following statements is not correct?
- A. Duration of study is shorter as compared to current cohort study.
- B. Control subjects are selected from the current population without exposure. (Correct Answer)
- C. Experience of cohort is assessed from existing records.
- D. Outcomes have occurred before the start of the investigation.
Explanation: ***Control subjects are selected from the current population without exposure.*** - In a **historical cohort study**, all data, including information on both exposed and unexposed (control) groups, is collected retrospectively from existing records. Control subjects are not usually selected from the current population. - The defining characteristic of a historical cohort is that both exposure and outcome have already occurred and are recorded prior to the study's initiation. *Duration of study is shorter as compared to current cohort study.* - This statement is correct. Because historical cohort studies utilize **pre-existing data** and outcomes have already occurred, the **follow-up period** from the researcher's perspective is significantly compressed compared to a prospective (current) cohort study. - The actual exposure and outcome events may have spanned many years in the past, but the time taken by the researcher to conduct the study is often shorter. *Experience of cohort is assessed from existing records.* - This statement is correct. A hallmark of **historical cohort studies** is their reliance on **retrospective data collection** from existing sources like medical charts, employment records, or birth registries. - Researchers do not actively follow up with individuals but rather consult these documents to track exposure and outcome status. *Outcomes have occurred before the start of the investigation.* - This statement is correct. In a **historical cohort study**, both the defining exposure(s) and the subsequent health outcomes of interest have already transpired by the time the study is initiated. - The investigator looks back in time to identify cohorts based on past exposure and then ascertains their outcomes from records recorded in the past.
Question 103: Iodine can be used for the disinfection of which of the following? 1. Water 2. Faeces 3. Urine 4. Skin Select the correct answer using the code given below:
- A. 1, 3 and 4
- B. 1 and 4 only (Correct Answer)
- C. 1, 2 and 3
- D. 1 only
Explanation: ***1 and 4 only*** - **Iodine is highly effective for water disinfection**, particularly in emergency and travel situations, killing bacteria, viruses, and protozoa - **Povidone-iodine is a standard antiseptic for skin disinfection** used pre-operatively, for wound care, and before injections due to its broad-spectrum antimicrobial activity - These are the two established and recommended uses of iodine for disinfection in medical and public health practice *1, 3 and 4* - While iodine effectively disinfects water and skin, it is **not used for urine disinfection** - Urine from healthy individuals is typically sterile and does not require routine disinfection - If disinfection of contaminated urine is needed (rare situations), other chemical agents would be preferred *1, 2 and 3* - Iodine is effective for water disinfection but **not suitable for faecal matter disinfection** - Faeces requires stronger disinfection methods: **chlorine-based compounds (sodium hypochlorite/bleach)**, heat treatment, or proper sewage treatment systems - Iodine is impractical and ineffective for the high pathogen load in faecal waste *1 only* - This option incorrectly excludes skin disinfection, which is **one of the most common applications of iodine** in medical practice - Povidone-iodine solutions (Betadine) are standard antiseptics used worldwide for skin preparation before surgical procedures
Question 104: Consider the following: 1. Standard deviation 2. Range 3. Mode 4. Median Among the above, which is/are the measure/measures of dispersion?
- A. 3 and 4 only
- B. 1 only
- C. 1 and 2 only (Correct Answer)
- D. 1, 2, 3 and 4
Explanation: ***1 and 2 only*** - The **standard deviation** quantifies the average amount of variability or dispersion around the mean, representing how spread out the data points are. - The **range** is the difference between the maximum and minimum values in a dataset, providing a simple measure of the total spread. *3 and 4 only* - The **mode** represents the most frequently occurring value in a dataset, which is a measure of central tendency, not dispersion. - The **median** is the middle value when data is ordered, also a measure of central tendency. *1 only* - While **standard deviation** is a measure of dispersion, this option incorrectly excludes the **range**, which also quantifies data spread. - Both **standard deviation** and **range** are fundamental measures used to describe the variability within a dataset. *1, 2, 3 and 4* - This option incorrectly includes the **mode** and **median**, which are measures of **central tendency**, not dispersion. - Measures of dispersion specifically describe the **spread or variability** of data, whereas central tendency measures describe the center of the data.
Question 105: Which of the following diseases has man as an incidental host with ‘Pig → Mosquito → Pig’ as the basic cycle of transmission?
- A. Japanese encephalitis (Correct Answer)
- B. Handigodu syndrome
- C. Chikungunya
- D. Kyasanur forest disease
Explanation: ***Japanese encephalitis*** - **Japanese encephalitis** is a viral disease where humans are incidental dead-end hosts. - The established transmission cycle involves **pigs as amplifying hosts** and mosquitoes (primarily *Culex tritaeniorhynchus*) as vectors, which then infect other pigs, maintaining the "Pig → Mosquito → Pig" cycle. - Water birds serve as natural reservoir hosts, while pigs amplify the virus. *Handigodu syndrome* - **Handigodu disease** is another name for **Kyasanur Forest Disease (KFD)** or a related viral hemorrhagic fever from the same region in Karnataka, India. - It is a tick-borne viral disease, not mosquito-borne, with monkeys and small mammals as reservoir hosts. - There is no "Pig → Mosquito → Pig" transmission cycle involved. *Chikungunya* - **Chikungunya** is a viral disease transmitted primarily by *Aedes aegypti* and *Aedes albopictus* mosquitoes, with humans being the primary reservoir hosts. - The transmission cycle is "Human → Mosquito → Human," not involving pigs as amplifying hosts. *Kyasanur forest disease* - **Kyasanur forest disease (KFD)** is a viral hemorrhagic fever transmitted by *Haemaphysalis* ticks, with monkeys and small mammals serving as reservoir hosts. - The transmission cycle involves ticks and forest animals, not pigs and mosquitoes, and humans are incidental hosts.
Question 106: A screening programme for school children was undertaken with the following results: 1. 30% boys and 60% girls were found to be anemic 2. 50% children had history of passing worms in stool 3. 10% children had poor vision 4. 5% children had enlarged tonsils In this context, which of the following is not an appropriate follow up activity?
- A. Referring those children with enlarged tonsils for surgery (Correct Answer)
- B. Providing iron supplementation to all children
- C. Administering mass deworming medication to all children
- D. Prescribing corrective spectacles to children with poor vision
Explanation: ***Referring those children with enlarged tonsils for surgery*** - Only **5%** of children had enlarged tonsils, and many cases of enlarged tonsils are **asymptomatic** and do not require surgery. - **Tonsillectomy** is a surgical procedure with risks and is typically reserved for recurrent infections or significant airway obstruction, which is not indicated by simple enlargement. *Providing iron supplementation to all children* - A significant proportion of children (30% boys, 60% girls) were found to be **anemic**, making universal iron supplementation a reasonable public health intervention to address widespread nutritional deficiency. - Iron deficiency is common in school-aged children and can impact **cognitive development** and physical performance. *Administering mass deworming medication to all children* - **50%** of children had a history of passing worms in stool, indicating a high prevalence of **intestinal helminthiasis** in the school population. - **Mass deworming** is a cost-effective public health strategy in areas with high prevalence to reduce the burden of worm infections and improve child health outcomes. *Prescribing corrective spectacles to children with poor vision* - **10%** of children had poor vision, a significant percentage that warrants intervention. - Providing **corrective spectacles** is an appropriate and effective follow-up to address refractive errors, which are a common cause of poor vision in children and can impact academic performance.
Question 107: Sullivan’s index is an indicator of:
- A. Morbidity
- B. Disability (Correct Answer)
- C. Mortality
- D. Health care delivery
Explanation: ***Disability*** - Sullivan's index, also known as **disability-free life expectancy**, is a measure that combines **mortality** and **morbidity** data to estimate the expected years an individual will live without disability. - It's a key indicator of the average number of years a person can expect to live in a **healthy or non-disabled state.** *Morbidity* - While related to morbidity, Sullivan's index specifically measures the **absence of disability**, rather than just the presence of disease or illness. - **Morbidity** refers to the state of being diseased or unhealthy, without necessarily quantifying the impact on daily function. *Mortality* - **Mortality** refers to the death rate or the number of deaths in a population. Sullivan's index uses mortality data in its calculation but is not solely an indicator of mortality. - It combines mortality with information on disability to provide a more nuanced picture of **population health.** *Health care delivery* - **Health care delivery** refers to the organization and provision of medical services. Sullivan's index measures health outcomes and does not directly indicate the quality or efficiency of healthcare delivery systems. - While improved healthcare can influence disability-free life expectancy, the index itself is a **health status measure**, not a healthcare system measure.
Question 108: Which one of the following mosquitoes is responsible for transmitting Japanese encephalitis?
- A. Aedes aegypti
- B. Anopheles stephensi
- C. Culex tritaeniorhynchus (Correct Answer)
- D. Mansonia
Explanation: ***Culex tritaeniorhynchus*** - This mosquito species is the **primary vector** for **Japanese encephalitis virus (JEV)** transmission in many endemic regions of Asia. - It typically breeds in **rice paddies** and other agricultural water sources, allowing for efficient transmission within populations. *Aedes aegypti* - This mosquito is the main vector for **Dengue**, **Chikungunya**, and **Zika** viruses. - It is not a significant vector for Japanese encephalitis. *Anopheles stephensi* - This mosquito is a major vector for **malaria**, particularly in urban areas of India. - It primarily transmits **Plasmodium parasites** and is not associated with Japanese encephalitis. *Mansonia* - Mosquitoes of the *Mansonia* genus are known vectors for **lymphatic filariasis** and some arboviruses. - They are not considered primary vectors for Japanese encephalitis.
Pediatrics
1 questionsWhich of the following are the features of Rubella? 1. Rashes appear within 24 hours of onset of symptoms 2. Incubation period is 2 – 3 weeks 3. False membrane is formed in throat 4. Post auricular lymph nodes enlarge Select the correct answer using the code given below:
UPSC-CMS 2014 - Pediatrics UPSC-CMS Practice Questions and MCQs
Question 101: Which of the following are the features of Rubella? 1. Rashes appear within 24 hours of onset of symptoms 2. Incubation period is 2 – 3 weeks 3. False membrane is formed in throat 4. Post auricular lymph nodes enlarge Select the correct answer using the code given below:
- A. 2 and 3 only
- B. 1, 2 and 4
- C. 1, 2 and 3
- D. 2 and 4 only (Correct Answer)
Explanation: ***Correct: 2 and 4 only*** - **Incubation period of 2-3 weeks** is accurate for rubella (14-21 days) - **Postauricular lymphadenopathy** along with suboccipital and posterior cervical lymph node enlargement are **classic hallmark features** of rubella, often appearing before the rash - These two features correctly identify rubella infection *Incorrect: 1, 2 and 4* - While statements 2 and 4 are correct, **statement 1 is medically inaccurate** - The rubella rash does NOT appear within 24 hours of symptom onset - Rubella typically has a **prodromal period of 1-5 days** with low-grade fever and malaise before the rash appears - The rash spreads from face to trunk within 24 hours, but this is different from appearing within 24 hours of initial symptoms *Incorrect: 2 and 3 only* - While the incubation period (statement 2) is correct, **false membrane formation in the throat** is characteristic of **diphtheria**, not rubella - Rubella does not cause pseudomembranous pharyngitis - This option also omits the classic postauricular lymphadenopathy *Incorrect: 1, 2 and 3* - Statement 1 is inaccurate regarding rash timing - Statement 3 describes diphtheria, not rubella - Only statement 2 (incubation period) is correct in this combination
Pharmacology
1 questionsWhich of the following is an example of ‘live attenuated vaccine’?
UPSC-CMS 2014 - Pharmacology UPSC-CMS Practice Questions and MCQs
Question 101: Which of the following is an example of ‘live attenuated vaccine’?
- A. D.P.T.
- B. Hepatitis ‘B’
- C. Typhoid (TAB)
- D. B.C.G. (Correct Answer)
Explanation: ***B.C.G.*** - The **Bacillus Calmette-Guérin (BCG)** vaccine is a **live attenuated vaccine** used worldwide for **tuberculosis prevention**. - It contains a live, but weakened, strain of *Mycobacterium bovis*, which stimulates a strong cellular immune response. *D.P.T.* - The **DPT vaccine** is a **combination vaccine** for diphtheria, pertussis (whooping cough), and tetanus. - It is currently available as an **inactivated vaccine**, specifically a **toxoid for diphtheria and tetanus** and either a whole-cell or acellular component for pertussis. *Hepatitis ‘B’* - The **Hepatitis B vaccine** is a **recombinant vaccine**, meaning it is produced using genetic engineering techniques. - It contains only the **surface antigen protein** of the Hepatitis B virus, not the whole virus, making it a non-live vaccine. *Typhoid (TAB)* - The **Typhoid (TAB) vaccine** is an **inactivated (killed) whole-cell vaccine** against *Salmonella Typhi*. - Newer typhoid vaccines, such as the polysaccharide vaccine and conjugate vaccine, are also non-live vaccines.