Question

100 patients with infectious hepatitis and 100 neighbourhood healthy control were questioned regarding a history of eating raw clams or oysters within the preceding 3 months.

-What is the study type/design?

-what were the key features in this text that assist you in deciding that this is the design?

-What are the advantage /disadvantage of using this design?

-What could be the research question or hypothesis of this study?

Answer 1

(a)

This is Observational study type/ design.

(b)

The key features in this text that assist you in deciding that this is the design: " were questioned regarding a history ...". From this, we understand that the researcher has no control over the variables. The researcher just gets relevant information without manipulation or intervention.

(c)

(i) Advantages of Observational study type/ design:

(1) Observational study enables researcher to elicit required information in real world aspect, in this case, effect of eating raw clams or oysters in infectious hepatitis directly from concerned individuals, instead of conducting separate experimentation.

(2) In some cases, such as the present case study, Observational study type/ design is the only technique for analysis of effect of eating raw clams or oysters in infectious hepatitis, since it is impossible to experiment with actual individuals.

(ii) Disadvantages of Observational study type/ design:

(1) there is a potential for subjective bias in Observational study type/ design. The researcher may unconsciously influence the participants in answering the questionnaire on effect of eating raw clams or oysters in infectious hepatitis.

(2) The accuracy of the results of Observational study type/ design is dependent on the proper interpretation, which is many times different from one researcher to another.

(d)

The research question or hypothesis of this study :

What is the effect of eating raw clams or oysters in infectious hepatitis?