UJI KLINIS RCT dan UN-RCTKursus Metodologi Penelitian PPDS

PREPARING THE RESEARCH DESIGN

Research design is the conceptual structure within which research would be conducted.

The function of research design is to provide for the collection of relevant information with minimal expenditure of effort, time and money.

The preparation of research design, appropriate for a particular research problem, involves the consideration of the following :1. Objectives of the research study.2. Method of Data Collection to be adopted3. Source of informationSample Design4. Tool for Data collection5. Data Analysis-- qualitative and quantitative

What Is Clinical Research?Research that takes place in clinical settingsCase studiesCase seriesDescriptive & retrospective studiesClinical trialsRandomized controlled trials

What Is A Clinical Trial?A research study in which a specific treatment is compared to a control conditionControl ConditionNo treatmentPre-treatment (pre- vs. post-)PlaceboStandard careAnother experimental intervention

Types of trials

Types Of ResearchDescriptive vs. AnalyticalApplied vs. FundamentalQuantitative vs. QualitativeConceptual vs. EmpiricalSome Other Types of Research

Quantitative researchQuantitative research often aimed at testing a research hypothesis. Involve the analysis of numerical data.Hypotheses = propositions about relationships between variables or differences between groupsEg. Do patients treated with drug A show greater improvement than those treated with Drug BOther quantitative studies aim to describe characteristics of a sampleEg. health needs of a local community

Quantitative techniques

Two main approaches:Surveys and questionnairesExperimental designs and intervention

Staging Clinical TrialsEfficacy vs. EffectivenessStages of DevelopmentDiscovery & pre-clinical studiesPhase I, II, III, IV

Efficacy and effectivenessEfficacy Does the intervention work in tightly controlled conditions?Strict inclusion/exclusion criteriaHighly standardized treatmentsExplicit procedures for ensuring complianceFocus on direct outcomes

Efficacy and effectivenessEffectiveness Does the intervention work in real world conditions?Looser inclusion/exclusion criteriaTreatments carried out by typical clinical personnelLittle or no provision for insuring complianceFocus on less direct outcomes (e.g., quality of life)

Efficacy and effectiveness studies optimize different aspects of validityclinical research [intervention] studies continuum:

EfficacyEffectivenessMost studies fall somewhere in between these anchorsExperimental (RCTs)Quasi-experimental/Observational designsInternal ValidityExternal ValidityFrom: Winstein & Lewthwaite, Eugene Michels Forum: CSM, Nashville TN, February 7, 2004

Experimental Study DesignA study in which a population is selected for a planned trial of a regimen, whose effects are measured by comparing the outcome of the regimen in the experimental group versus the outcome of another regimen in the control group. Such designs are differentiated from observational designs by the fact that there is manipulation of the study factor (exposure), and randomization (random allocation) of subjects to treatment (exposure) groups.

Experiments

Enables researchers to demonstrate how manipulating one set of variables (independent variable) produce systematic changes in another set of variables (outcome or dependent variables)

Why Performed ?Provide stronger evidence of the effect (outcome) compared to observational designs, with maximum confidence and assuranceYield more valid results, as variation is minimized and bias controlledDetermine whether experimental treatments are safe and effective under controlled environments (as opposed to natural settings in observational designs), especiallywhen the margin of expected benefit is doubtful / narrow (10 - 30%)

Experimental DesigntimeStudy begins here (baseline point)StudypopulationInterventionControloutcomeno outcomeoutcomeno outcomebaselinefutureRANDOMIZATION

Experimental DesignAdvantagesBest establishes cause-and-effect relationshipsDisadvantagesArtificiality of experimentsFeasibilityUnethical

Characteristics of True DesignsManipulation (treatment)RandomizationControl group

**Difficult to establish cause-and-effect.Correlational research often done first to establish relationships that may be examined for cause-and-effect.Cause-and-effect are not established by statistics but rather by logical thinking and sound research design. You must establish that no other plausible explanation exists for the changes in the DV except the manipulation done to the IV.