basic research design

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Basic Research Design

Understanding and Using the Designing a Research Project

Worksheet

Major Parts of a Research Project

1) Overall Research Question

2) Type of Design

3) Setting

4) Participants

5) Variables

6) Hypotheses and Research Questions

7) Statistical Testing

Article Used in This LectureHungford, D. W. Williams, J. M., Furbee, P. M., Manley, W. G., Helmkamp, J. C., Horn, K., and Pollock, D. A. (2003). Feasibility of screening and intervention for alcohol problems among young adults in the ED. American Journal of Emergency Medicine, 21, 14-22.

Overall Research Question

What do you actually hope to learn during your study?

Hungerford et al. study:

Is it feasible to screen and perform a brief alcohol intervention with young adults in the ED?

Type of Design• Survey

• Epidemiological / Data Mining

• Randomized Study

• Nonrandom Study

Survey• Person-2-Person

• Other Outlet

• Mail

• Web Based

Epidemiological / Data Mining

• Personally Collected Data

• Government Agency Data

• Hospital Records

• Other Source of Data

Ecological Study

Use data collected about populations and compare them to other populations. No actual measure of exposure is done.

Ecological Fallacy

Communities may differ in many factors, and one or more of these may be the underlying reason for difference in observed disease and death rates.

Randomized Study

• Non-Blinded Study

• Single Blinded Study

• Double Blinded Study

Nonrandomized Study

• Case-Control

• Cohort

Case Control Study

Start with people who have a specific outcome (disease), and attempt to work backwards to find out if there was exposure to a hazard of interest.

Cohort Study

Researcher observes health outcomes of a group that has potential exposure to a hazard over a period of time.

Hungerford et al. study:

Mixed Design

•Survey•Non-randomized design

-- Cohort Study

Types of Experimental

Designs

• O1 = Observation #1

• O2 = Observation #2

• X = Study Intervention

• Group (Which research group does someone belong?)

Basics of Study Design

Pre-experimental Designs

One-Shot Case Study Design

X O• Expose someone to the

intervention and then observe the outcome.

• You really do not know if your intervention causes the change.

One group pretest – posttest design

O1 X O2

• Still a problem of unknown intervening variables (variables that cause the change that you are not measuring).

Static Group Design

Set Group 1 X O1Set Group 2 O1

• Two set groups (EOH and OVMC) and all at EOH get the IV.

• You do not know if there are initial group differences.

True Experimental

Designs

Pretest-Posttest Control Group Design

Group 1: O1 X O2Group 2: O1 O2

• The outcome can be effected by exposure to the pretest when an IV is given.

• If you are given a test, then taught, and then given the same test – You’ll perform better because you knew what to look for during the lesson.

Posttest-Only Control Group Design

• It is more economical.

• Eliminates the possibility of pre- and posttest interactions.

Group 1: O1 X O2Group 2: O2

Solomon Four-Group Design

Group 1: O1 X O2Group 2: O1 O2Group 3: X O2Group 4 O2

• This design corrects for the flaws in the other designs.

Hungerford et al. study:

This study was a One-shot Case Study. Everyone who participated in the study received the intervention.

Setting of Study

Where will the survey/study be conducted?

Hungerford et al. study:•Rural, University Based ED•Study happened only between noon and 1 AM (for peak hours).•School associated with the hospital has been ranked by The Princeton Review for being the #1 party school.

Participants

1)Will your participants have specific characteristics?

2)How will you select/acquire your participants?

3)Do you need a letter of consent?

1)Will your participants have specific characteristics?

Hungerford et al. study:

All participants had to be between the ages of 18 & 39.

Only participants who had consumed alcohol in the previous 12-months were included.

2) How are you going to select/acquire participants?

Hungerford et al. study:

Participants who did not speak English, were combative, or were too drunk for participation were excluded from the study.

All participants were recruited between the dates of August 1, 1998 to June 9, 1999.

3) Do you need a letter of consent for participation?

Hungerford et al. study:

YES!!!

Variables

Any entity that can take on different values.

Dependent Variables

The variable that is effected or not effected by another variable in a research study.

Independent Variables

The variable that is being manipulated or examined in a study to see if it effects the dependent variable.

Example

In a study by Wrench and Booth-Butterfield (2001), it was found that a physician’s humor orientation influenced her or his patient’s level of satisfaction.

What was the IV and DV?

IV = Physician Humor Orientation

DV = Patient Satisfaction

Levels of Measurement

1)Independent Variables

-- Screen Positive or Screen Negative (aka were they heavy or non-heavy drinkers)

-- Legal or illegal drinking age

Hungerford et al. study:

1)Dependent Variables• Post intervention alcohol moderation• Post intervention help-seeking

behaviors• ED staff perceptions of participant

cooperation

Hungerford et al. study:

Research Questions and Hypotheses

Research Questions (RQs): Questions that you want specifically answered through your data.

Hypotheses (H): Predictions you make about data associations in your study based on previous research.

ActivityBased on the DVs and IVs from the Hungerfold et al. study, can you identify any logical research questions to ask?

RQ1: Will there be a difference between the screen positive and negative participants and their post intervention alcohol moderation behavior?

Hungerford et al. study:

RQ2: Will there be a difference between the legal and illegal alcohol consumers and their post intervention help-seeking behavior?

RQ3: Will the ED staff see the screen Positive and Negative participants as being equally cooperative?

RQ4: Will the ED staff see the legal and illegal alcohol consumers as being equally cooperative?

H3: The ED staff will see the screen negative participants as being more cooperative than screen positive participants.

H4: The ED staff will see the legal alcohol consumers as being more cooperative than the illegal alcohol consumers.

Statistical TestingOnce you know what your research questions / hypotheses and you know the level of measurement of your IVs and DVs, the statistical determination is very easy.

See Picking a Test Handout

Prepared by:Jason S. Wrench, Ed. D.

Medical Educational SpecialistWest Virginia School of Osteopathic Medicine

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