Question

a. What are the research reliability and validity? What is internal validity and construct validity? What are the difference between reliability and validity?

b. Please describe research hypothesis and statistical hypothesis. What are the difference between these two kinds of hypotheses?

c. What are three level of research? Exploratory research, descriptive research and explanatory research? What are the difference between them?

d. What are case-control design, nested case-control design, and cohort design? What are the difference between case-control design and population-based case-control / nested case-control design, and cohort design?

e. Please define the relative risk (RR) and odds ratio (OR). What is the difference between relative risk and odds ratio?

f. Please describe the number needed to treat (NNT) and number needed to harm (NNH). What is the difference between NNT and NNH?

Answer 1

a-Research quality is evaluted through research reliability and validity. Research reliability means the methods and techniques used to get the data and test are reliable or not. Validity means accuracy of the data.

internal validity means there must the a relation between the research question and the result and not any other reason or facctors .

Construct validity measures how well the result got from test are accurate.

b-Research hypothesis can be general type related to observations,life style etc.Statistical hypothesis is based on variables and done with systematic approach.

c-These are types of research

1-Exploratory-To explore some idea or insights into some known or unknown subject.Like Covid 19

2-Descriptive-To describe some event or happening of something.

3-Explanatory-It defines the cause and effect of something and explain the event.

D.case control design means the study in which the outome gathered on the basis of supposed causal attribute.Like patient have syptomes of covid 19 and how they recovered.

nested case-control design,-cases and controls are drawn from the population in a fully enumerated cohort .

cohort design=These means like in case of Covid 19 patient whole country is under observation and every thing is measured so as to reduce the level of infected patients.

The design with some common charaterisctics and represented by sample/population.