Question 31: Data obtained from hospital records is not a representative sample of the population. What are the reasons for this ?
I. Mild cases and subclinical cases may be missed.
II. Population served by a hospital usually cannot be defined.
III. Cost of hospital care is not recorded.
IV. Admission policy for cases can vary from hospital to hospital.
Select the correct answer using the code given below :
- A. II and III only
- B. II, III and IV
- C. I and II only
- D. I, II and IV (Correct Answer)
Explanation: ***I, II and IV***
- Hospital records tend to miss **mild or subclinical cases** because these individuals may not seek hospital care, leading to an underrepresentation of the true disease prevalence.
- The **population served by a hospital is often ill-defined**, making it difficult to generalize findings to a specific community or broader population.
- **Admission policies vary between hospitals**, meaning the types of cases seen at one institution might differ significantly from another, affecting sample representativeness.
*II and III only*
- While the **population served by a hospital is often ill-defined** (II), the cost of hospital care not being recorded (III) does not directly make the sample unrepresentative of the population's health status or disease prevalence.
- The lack of cost data primarily impacts financial analysis, not the epidemiologic representativeness of patient data.
*II, III and IV*
- The statement that the **population served by a hospital usually cannot be defined** (II) and that **admission policies vary** (IV) are valid reasons for non-representativeness.
- However, the **cost of hospital care not being recorded** (III) is not a direct reason why hospital data would fail to represent disease patterns or demographics of the general population.
*I and II only*
- Missing **mild and subclinical cases** (I) and an **ill-defined target population** (II) are valid reasons for unrepresentative data.
- However, this option omits the crucial point that **hospital admission policies vary** (IV), which significantly influences the types of cases included in hospital records and their generalizability.