Material and methods part 1
Material and methods part 2
MATERIAL AND METHODS LAYOUT
CROSS SECTION STUDY
Outline
- Population/patients
- Screening
- Procedures/Survey
- Definition of variables
- Ethical clearance
- Statistical analysis
Population/patients
- Provide a brief outline of
- study population
- clinical services in question
- Study location/ area
- participants
- study areas and disease/ case distribution
- Location /area where the participants were recruited
- Hospital base
- Population base
- Duration of study: for e.g. From Nov 1, 2003, to Sept 30, 2014,
Screening/Survey
- screening / survey method is described with references
- staff qualification an training
- Quality-control measures to check data completeness and consistency.
- Define questionnaire/investigation/procedures
Procedure
- Preliminary data
- demographic data
- questionnaires
- surveys
- examination
- cases:
- diagnostic criteria
- inclusion and exclusion criteria
- Outcome
- The primary endpoint
- Secondary end points
Ethical clearance
- Written informed consent
- Study protocol was approved by Regulatory Agency/ethics committee
- Study was done in accordance with the principles of the Declaration of Helsinki and the International Council for Harmonization Good Clinical Practice guidelines.
Definition of variables
- Definition of variables
- Study variables
- Outcome variables
Statistical analysis
- Null hypothesis
- Power and alpha
- Sample size calculation and expected power of the study.
- Statistical methods adopted to calculate
- The primary endpoint
- primary analysis
- categorical exposure variables(association between outcome and intervention)
- Odd ratio
- Confidence interval, Confidence level
- Comparative evaluation of any study variable to predict disease
- logistic regression models
- model-fitting info
- Secondary end points
- categorical exposure variables(association between outcome and intervention)
- Data analysis software
- primary analysis
Sample size calculation

Confidence level: 95% p < 0.05, Z= 1.96
Confidence level: 99% p < 0.001, Z= 2.58

CASE CONTROL STUDY
What is a case control study?
Example of case control study
Outline
- Population/patients
- Cases and control
- Procedures/Survey
- Definition of variables
- Ethical clearance
- Statistical analysis
Population/patients
- Provide a brief outline of
- study population
- clinical services in question
- Study location/ area
- participants
- study areas and disease/ case distribution
- Location /area where the participants were recruited
- Hospital base
- Population base
- Duration of study: for e.g. From Nov 1, 2003, to Sept 30, 2014,
- Sample size
- Sample size
- Cases
- control
- randomization
- Matching criteria for cases and controlling
- Matching ratio between cases and control
- Recall bias
Cases and control
- Case and control
- Inclusion criteria
- Exclusion criteria
- Matching criteria (in the video below)
- Matching ratio
Matching criteria
Procedure
- Preliminary data
- demographic data
- Cases and control
Variables
- Dependent variable /outcome variable
- Independent variables /comorbidities
Ethical clearance
- Written informed consent
- Study protocol was approved by Regulatory Agency/ethics committee
- Study was done in accordance with the principles of the Declaration of Helsinki and the International Council for Harmonisation Good Clinical Practice guidelines.
Descriptive analysis of the study variables
- qualitative variables
- frequencies and percentages
- quantitative variables
- means and SD
- Differences between means
- t test for independent data
- To compare proportions within the group of cases,
- The χ2test or the Fisher exact test for expected values of less than 5.
Odd ratio
- to compare the odds of developing primary study outcome( dependent variable) for each co-morbid condition(independent variable)
- Crude odds ratios (ORs) and 95% confidence intervals (CIs)
- univariate logistic regression analysis for both groups.
- The resulting ORs were also adjusted for matching criteria.
- The resulting ORs were also adjusted for matching criteria for case and control.
Calculating the odds ratio