prof. zekeriya aktürk 26.02.2011, sana’a

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Prof. Zekeriya Aktürk

26.02.2011, Sana’a

Research Methodology Research Methodology and Practical Biostatistics and Practical Biostatistics

Using SPSSUsing SPSS

- Introduction -- Introduction -

http://aile.atauni.edu.tr

zekeriya.akturk@gmail.com

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Aims and Objectives• At teh end of this presentation, the participants should

be aware of basic research methodology and be equipped with the information to conduct a research.

• Objectives– List stages of a research– Ask a clinically answerable question– Classify types of data– Count basic hypothesis tests and their usage– Define types of study designs

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Let us do a research togetherStatistics course participants and reasearch

Aktürk Z. Sana’a, February 25, 2011

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One literature

Askew, DA. et al. GPs involvement in and attitudes to research. Med J Aust 2002;177(2):74-77

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Stages of a research

1. Ask an answerable question2. Is the question already answered?3. Formulate hypothesis4. Decide on the method5. Application6. Analysis7. Interpret results8. Write report

Tyler CW, Epidemyology

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Most important: IdeasMy research logbook

Idea Method Application Reporting1. Usage of herbal

medicine among public

2. Effect of constipation on cognitive functions

3. …

1. Medical specialization training in Turkey

2. .

1. The effect of structured exercise on weight loss

2. Developing a national EMR database

3. .

1. Prevalence of osteoporosis in Edirne

2. Knowledge of herbs by medical students

3. .

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Answerable clinical question•Patient/problem•Intervention•Comparison•Outcomes

Is there a difference between a calorie diet and a glycemic diet in decreasing the body mass index of obese patients?

Centre for EBM http:www.cebm.net/

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Formulating the hypothesis

• H0 – There is no difference between a calorie diet and a

glycemic diet in decreasing the body mass index of obese patients.

• H1 – There is a significant difference between a calorie diet

and a glycemic diet in decreasing the body mass index of obese patients.

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Study designs(How to answer the question?)

• Observation– Case report– Prevalence– Case control– Cohort studies

• Intervention– Randomized controlled studies

• Methodological– Reliability-Validity– Sensiivity-Specifity

Case-Control Study

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Cohort study

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RCT

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Analysis – Data types

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Choosing the correct test

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Question

• Is there any significant difference between class 1 and class 6 medical students in recognising thyme?

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Hypothesis

• H0: There is no significant difference between class 1 and class 6 medical students in recognising thyme?

• H1: There is significant difference between class 1 and class 6 medical students in recognising thyme?

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Method

• Showing the picture of thyme plant to class 1 and class 6 medical students and asking whether they recognize it

Analysis - Frequencies

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Analysis – Hypothesis test

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Interpretation

• While 12% of class 1 students recognized thyme, this was 78% in class 6

• Although class 6 students are better in recognizing thyme, even among them 22% failed.

• There is a significant difference between class 1 and class 6 medical students in recognizing the picture of thyme (p<0,001).