SELECTING RESEARCH DESIGN Yulia Sofiatin COMMUNITY RESEARCH PROGRAM 5 2012

RESEARCH METHODOLOGY Formulating research problem Conceptualizing research design Constructing instrument Selecting samples Reporting Data processing Research proposal Data collection

Choose the most appropriate study design for each study objective/title : Qualitative study Cross-sectional Case-control Cohort study Experimental study Descriptive study Case-report

Mother’s perception on oral rehydration in West java The effect of peer-education on student’s sexual activity Carbohydrat isolation in several kind of peas Incidence of stroke in families with and without family history of hypertension Measurement of FEV1 of 100 medical students after 30 minutes Treadmill exercise Comparison of FEV1 of 100 medical students before and after 30 minutes/day aerobic exercise for 3 months

Association between breast cancer and number of cigarette smoking in women. Pattern of bone fracture in patients with motorcycle accident admitted to Emergency Room, Hasan Sadikin Hospital. Correlation between the knowledge of peer-educator and peer’s knowledge on smoking cessation. Rare experience: treatment of severe distribution shock after albumin administration in male patient with lupus nephritis

Time line of different study design Cross Sectional Case Control Cohort study Case Report T i m e l i n e ` Case Series Clinical Trial

Case control Starting point With disease CONCLUSION Without disease Exposure A With disease CONCLUSION Exposure B Without disease

Cohort Starting point With disease CONCLUSION Without disease Exposure A With disease CONCLUSION Exposure B Without disease

Cross-sectional Study Metformin Population Sample Compl (+) Compl (-) Sulfonil urea Compl (+) Compl (-)

Clinical Trial Outcome Treatment No Yes Sample Placebo No Yes CONCLUSION Placebo No Yes Population Random selection Blinded administration

Laboratory experimental Disease Effect Population Treatment No Yes Sample CONCLUSION Objects Placebo No Yes Random selection Control Blinded administration

Selection of study design depends on: Research question/problem/objective Time & resources availability Common/rare disease Expected outcome Quality of data Established design

Although screening of blood donors prevents HCV infection through blood transfusion, the prevalence of the infection remains high in patients who are on chronic hemodialysis, presumably because of previous frequent blood transfusions and nosocomial transmission. A recent study in patients with normal renal function showed that interferon treatment lowered the rate of the occurrence of hepatocellular carcinoma by a factor of 2, whereas another study reported that the therapy improved the survival but did not reduce the risk of liver disease in chronic hepatitis C. The therapy has also been applied to hemodialyzed patients, but several limitations compromise its usefulness for these patients: Interferon is expensive, liver biopsy for definite diagnosis is reported to be risky for hemodialyzed patients because of their tendency of bleed, the therapy may cause serious adverse effects, and, most important, the natural history of HCV infection in hemodialyzed patients is unclear. J Am Soc Nephrol 11: 1896–1902, 2000

Based on the article above, several problems arise Based on the article above, several problems arise. Choose the most appropriate study design for each study questions. Cross sectional study Cohort study Case control study Clinical trial Experimental study Qualitative study

Choose the most appropriate research design Is screening to blood donors in our facility conducted in an appropriate manner? How big is the correlation between blood transfusion and HCV infection in our setting? How long does it take for a chronic hemodialysis patient to suffer HCV infection? Is interferon in our patients as effective as in patients in the research?