The components of a research

The research question The research question is: uncertainty in the universe the investigator really wishes to settle, the clinical study is the oparationalized counterpart addressed by the study plan.

Imagination & creativity The research question: is the objective of the study; often begins with a vague and general concern that must be narrowed, it is originated from : Build on experience Be alert to new ideas Imagination & creativity Methods of hypothesis formulation: Method of agreement Method of deference Method of concomitant variation

So it should be: A concrete researchable issue Interesting Pass the “So what” test. Ethical Feasible to study (No.,Cost,technique expertise) Relevant

Dynamics Research Question Study plan actual study Findings in the study Truth in the study truth in the universe Implement design Inference1 Inference2 External Validity Internal validity

Summary A good way to develop the study plan is to write a one sentence summary and to expand this into 1-2 pages outline that sets out the study elements in a standardized sequence later on the study plan will be expanded into the protocol of the operations manual.

The Inference The final inference that will be drawn from the study subjects to the pop. At issue here are the relationships between:- The research quest. (what the investigator really wants to answer) The study plan (what the study is designed to answer) The actual study (what the study will actually answer)

Sampling Pop.: is a set of units,the perfect way of research is to study the whole pop., but this is usually (but not always) difficult to what feasible, so we take a sample of the pop., this is done in three steps: 1-Define the target pop.: large set of all patients or people throughout the world to whom the results will be generalized) depending on clinical and demographic characteristics (ex. All teenagers with asthma). 2- Define the accessible pop. (subset of the target pop. that is available for the study depending on geographic and temporal characteristics (ex. Teenagers with Asthma living in Baghdad during the year 2007) 3- Define the sample: which is selected from the accessible pop. by either randomized (probability) or non-randomized (non-probability) method of sampling. It should be representative for the accessible pop. & easy to do.

Recruitment:- We have two main goals: 1-To recruit enough subjects to meet the sample size requirement 2-To recruit a sample that is unbiased

Re capping the errors in choosing the sample:- The advantage of sampling is efficiency, it allows the investigator to draw inferences about a large population at relatively small cost in time and effort .The disadvantage is the sources of error it introduces which are either: Design error: in selecting the suitable subject for the research. Implementation error: By choosing a non-representative sample (for ex. Selection bias,….) The art of designing the protocol for acquiring study subjects is to find the best compromise between the prevention of errors of the reasonable cost in time and money.

Research question study plan actual study Target Pop. Intended sample actual subjects Findings in the Truth in the Truth in the study study universe implementation design