Title: Dr. S. Nishan Silva
1Research Methodology
- Dr. S. Nishan Silva
- (MBBS)
2Stages in the Research Process
Define Problem
Planning a Research Design
Conclusions and Report
Planning a Sample
Processing and Analysing the Data
Gathering the Data
3Research Process Research Process Research Process
Phase I Preparation Phase Phase II Implementation phase Phase III Outcome Phase
1. Select a problem for research 7. Collect the data 9. Interpret research findings.
2. Literature review 8. Analyse data 10. Report the study
3. Formulate research question
4. Select research approach and design
5. Select data collection method.
6. Specify a population
4Research Methods - Timeframe
- Research Project
- Develop Research Proposal
- and obtain approval
- Develop and test questions
- Develop and test tool
- Obtain participants
- Administer instrument(s)
- Ongoing data collection and analysis
- Final collection of data
- Research Report
Day 344
51. Problem Identification and statement of
research problems
- Sources to identify problems
- Nursing experience
- Personal, of collegues
- Of hospital records
- Nursing Literature
- Nursing journals, books
- Theory
- Text books
62. Process of Selecting a Research Problem
- The topic is RESEARCHABLE
- The question is THEORY BASED
- The research is a feasible project
- The researcher has the ability to carry out the
study
73. Writing a problem statement
- Convert the topic in to a STATEMENT
- Question, statement or hypothesis
- A hypothesis is a statement of predicted
relationship or difference between two or more
variables
8A good research statement should have,
- Area of focus
- Population
- Research design
- Setting of the study
9Different levels of research problems
- Level 1
- One variable
- One Population
- Level 2
- Two variables
- Relationship between them
- Level 3
- Experimental type designs, finding causes
- Manipulation of one variable to find its effect
on the other
104. Define Variables
- What is a variable?
- A characteristic, property or attribute of the
person or thing under investigation.
11Types of variables
- Dependant Variable
- It is the researched, observed variable
- It changes according to the manipulating variable
- Independent Variable
- The variable that is manipulated
- Extraneous variable
- Other variable (outside the research) that can
interrupt - May be controlled increase accuracy
- Discrete variable
- A variable that it finite a whole number ex-
days, patients - Continuous variable
- That is infinite
- Spans a range
12Defining variables
- Conceptual definition
- Defining as it is understood
- Ex- Social class
- Operational definition
- Working definition
- Definition to be used in the research
- Ex Fathers usual occupation as stated by the
Mother
135. Literature review
- Definition
- It is a critical summery of available theoretical
and research literature on the selected research
topic.
14Finding Literature
- Library catalogues manual and electronic
- Indexes and abstracts
- Ex MEDLINE, CINAHL, PubMED
- e-Medicine
15- Guidelines in doing the Review
- Search for existing literature in the library and
on the web
- 2. Prepare a working bibliography. Record all
vital details concerning the books or research
you are including in your bibliography - Write in index cards group together references
from a. booksb. journals and periodicalsc.
unpublished material - 3. Examine each material, then decide which ones
will actually be included in your review
166. Population and sample
- Population define as much as possible
- Time bound?
- Geographically bound?
- Process of selecting a sample sampling
- Bias?
- Therefore
- Probability sampling
- Non probability sampling
17Developing a Sampling Plan
- Define the Population of Interest
- Identify a Sampling Frame (if possible)
- Select a Sampling Method
- Determine Sample Size
- Execute the Sampling Plan
18Defining Population of Interest
- Population of interest is entirely dependent on
Management Problem, Research Problems, and
Research Design. - Some Bases for Defining Population
- Geographic Area
- Demographics
- Usage/Lifestyle
- Awareness
19Probability Sampling
- Simple Random Sampling
- Everyone has a chance of getting included
- Random numbers table
- Stratified Random Sampling
- Population divided in to strata segments
- Then do simple random sampling for each strata
- Systematic Sampling
- Using every -----th person.
20Random numbers table
21Non-probability Sampling
- Convenience sampling
- Also called accidental. As you meet them.
- Purposive sampling
- Judgemental sampling
- Selects groups according to criteria
- Quota sampling
- Quotas from pre-decided characteristic groups
- Convenience sampling within a group
- Cluster sampling
- Multistage sampling
- Larger clusters and smaller clusters within
22Multistage Sampling
- Stage 1
- randomly sample clusters (schools)
- Stage 2
- randomly sample individuals from the schools
selected
23Determining Sample Size
- How many completed questionnaires do we need to
have a representative sample? - Generally the larger the better, but that takes
more time and money. - Answer depends on
- How different or dispersed the population is.
- Desired level of confidence.
- Desired degree of accuracy.
24Other factors
- Inclusion criteria?
- Who gets in?
- How to filter?
- Exclusion criteria?
- Who stays out?
- How to determine?
257. Research Design
- Quantitative Research
- Experimental Designs
- Non-experimental Designs
- Descriptive Design
- Exploratory Design
- Co-relational Design
- Retrospective Design
- Quasi-experimental Designs
- Qualitative Research
26Experimental Designs
- Researcher manipulates variable/s
- The design uses control groups
- The selection of sample is based on random
sampling
27Non-Experimental Designs
- Descriptive Design
- Description of a data collection on several
variables - Exploratory Designs
- To find out relationship between dependant
variable and independent variable without any
manipulations . (Observe as it is) - Co-Relational research Design
- Relationship between two variables in the same
sample - Retrospective Design
- Collect data on variables after they have
happened (looking back at the past).
28Cross-Sectional Versus Longitudinal Studies
- Cross-Sectional Studies
- A study can be done in which data are gathered
just once, perhaps over a period of days or weeks
or months, in order to answer a research
question. - Longitudinal Studies
- Studying people or phenomena at more than one
point in time in order to answer the research
question. - Because data are gathered at two different
points in time, the study is not cross-sectional
kind, but is carried longitudinally across a
period of time.
29Quasi-Experimental Research
- Researcher does manipulate the independent
variable - But unable to randomly allocate
- Uses a convenient sampling method to form the
sample.
30Qualitative Research
- What? Why? How?
- Data words / pictures etc
- The unfolding process determines the next step
- Researcher is the key instrument of data
collection - Open ended questionaires / Interviews / Video
recordings / Observations
31Qualitative - Definition
- qualitative researchers study things in their
natural settings, attempting to make sense of or
interpret phenomenon in terms of the meanings
people bring to them. (Denzin Lincoln, 2000,
p.3).
32Qualitative Research Designs
- Descriptive / Exploratory Design
- Interpretative Design
- Ethnography
- Anthropological
- Methods Interviews/ Observations / Records /
Life history facts / news reports / Diaries - Phenomenology
- What it is like to have a certain experience?
- Ask peoples real life experiences / use novels/
films - Ground Theory
- Researcher formulates tentative theories using
inductive reasoning - Follows up those ideas with further enquiry
deductive reasoning
33Data Collection methods
- Types of data to be collected
- Quantitative Data
- Data that is collected as numbers
- Qualitative data
- As words, pictures, documents, Photos
34Data Collection Methods and Instruments
- Bio-Physical measurements
- Observations
- Questionnaires
- Advantages?
- Disadvantages?
- Interviews
- Unstructured Open ended questions
- Structured Close ended questions
- Interview schedules and interview guides
- Advantages ? Disadvantages?
35Issues in research instrument
- Suitable for use
- Language / Culture
- Based on theory frame of the study
- Should test the theory / not too much of other
info. - Collect adequate info
- Valid / Reliable / Un-biased
- Accurate
- Protocol
- Simple directions for users
- Uncomplicated
- Easy to administer
- Not taking too much time / effort
36Pilot Project
- Smaller version
- Test the instrument (questionnaire)
- Small sample from the same or similar population
- Sort out problems
- Understandability
- Validity
- Accuracy
37Reliability and Validity
- Reliability
- Basic sources of inaccuracy
- Deficiency (error)
- Inconsistency between readings
- Methods to test reliability
- Test-retest method
- Same test twice with a rest in between
- Equivalent Test
- Two tests given to two samples with different
behaviors - Split half method
- Separate scores for even numbered and odd
numbered items analyzed. -
38Reliability and Validity
- Validity
- Types of Validity
- Predictive validity
- Ability of the instrument to predict future
behavior - Content validity
- Adequacy of coverage
- Concurrent validity
- Ability to differentiate people based on a
criterian - Construct validity
- Whether the theory is measured or something else
is? - Face validity
- Whether it appears to be valid
39Data Analysis
- How to process the collection (?papers)
- Master data sheets
- Coding
- Master tables
- Statistics
40Flowcharting the Research Process (2)
Survey (Interview, Questionnaire) Experiment
(Laboratory, Field) Secondary Data
Study Observation
Collection of Data (Fieldwork)
Editing and Coding Data
Sample Design
Data Processing and Analysis
Interpretation of Findings
Probability Sampling
Non-Probability Sampling
Report
41Read Research Statistics Chapter
42The MOST IMPORTANT TIME for the statistics to be
involved with a research study is in the very
BEGINNING
STATISTICS CAN HELP OBTAIN THE MAXIMUM AMOUNT
INFORMATON FROM AVAILABLE RESOURCES
43HOW??? HELP WITH THE DESIGN OF THE
EXPERIMENT DETERMINE SAMPLE SIZE NEEDED DEVELOP
PROCESS OF COLLECTING DATA DISCUSS VARIABLES TO
BE MEASURED AND HOW THEY RELATE TO THE OBJECTIVES
OF THE STUDY PROVIDE METHODS OF ANALYZING THE
DATA HELP TRANSLATE STATISTICAL CONCLUSIONS INTO
SUBJECT MATTER CONCLUSIONS
44Why Use Statistics?
- Descriptive Statistics
- identify patterns
- leads to hypothesis generating
- Inferential Statistics
- distinguish true differences from
- random variation
- allows hypothesis testing
45Describing the Data with Numbers
- Measures of Central Tendency
- MEAN -- average
- MEDIAN -- middle value
- MODE -- most frequently observed value(s)
46Describing the Data with Numbers
- Measures of Central Tendency
- MEAN -- average
- MEDIAN -- middle value
- MODE -- most frequently observed value(s)
47Histogram-Frequency Distribution Charts
This is called a normal curve or a bell
curve This is an idealized curve and is
theoretical based on an infinite number derived
from a sample
48The Normal Curve and Standard Deviation
A normal curve Each vertical line is a unit of
standard deviation 68 of values fall within 1
or -1 of the mean 95 of values fall within 2
-2 units Nearly all members (gt99) fall within 3
std dev units
49Terms
- confidence interval
- The range of values we can be reasonably certain
includes the true value.
5095 Confidence Intervals
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