1. Formulation of the objectives Variable vs
Formulation of the objectives Variable vs. Concepts Types of measurement scales
Dr. Sa’ed H. Zyoud

2. Formulation of the objectives
They are the goals you set out to achieve in your study.
You should word them clearly and specifically (so as to be clear to the reader).
Two types
General (main objective).
The main association/relationship you want to discover or establish.
Specific (sub-objectives).

3. Formulation of the objectives
Specific (sub-objectives).
Specific aspects of the topic that you want to investigate within the main framework of your study.
Numerically listed.
Wording should clearly, completely and specifically
Each objective should contain only one aspect of the Study.

4. Formulation of the objectives
The objectives should start with words such as:
‘to determine’
‘to find out’
‘to ascertain’
‘to measure’
‘to explore’

5. Formulation of the objectives
The wording of objectives determines the type of research
- Descriptive, Correlational, Experimental
The wording of objectives determines the type of research design you need to adopt to achieve them
- Observational study, Experimental study

6. Formulation of the objectives
Descriptive studies:
-To describe the care provided to diabetic patients.
-To find out the opinion of the patients about the medical facilities provided to them.
- To describe the demographic and clinical characteristics, risk factors and comorbidities of patients admitted with ischemic heart disease.
- To describe the medications given to diabetic patients at discharge.

7. Formulation of the objectives
Correlatinal studies:
-To ascertain the impact of anticoagulant use on the risk of thromboemobolism.
-To compare the effectiveness of warfarin and heparin on the risk of thromboemobolism.
- To assess the potential benefits of previous aspirin use on reducing mortality after ischemic heart disease.
- To determine the variables upon admission that are considered the most predictive of in-hospital mortality among ischemic heart disease.

8. Formulation of the objectives
-To ascertain if an increase in working hours will increase the incidence of drug/alcohol abuse. - To determine if the previous aspirin use can reduce mortality after ischemic heart disease.

9. Formulation of the objectives
Characteristics of the objectives
Clear
Complete
Specific
Identify main variables to be correlated
Identify the direction of the relationship

10. Formulation of the objectives
- Identify main variables to be correlated
The concepts used should be set in measurable terms so that the extent of variations in respondents’ understanding is reduced if not eliminated.
Techniques about how to operationalise concepts, and knowledge about variables, play an important role in reducing this variability.

11. Formulation of the objectives
- Identify main variables to be correlated
When people express their feelings or preferences, they do so on the basis of certain criteria in their minds. Their judgment is based upon indicators that lead them to conclude and express that opinion.

12. Definition of the Variable

13. Variable vs. Concepts
- Variable:
Can be measured via a specific scale.
- Concepts
mental images or perceptions, and their meaning vary from individual to individual (subjective impression) and can be converted into variables by indicators.
indicators- a set of criteria reflective of the concept which can then be converted into variables. .

14. Variable vs. Concepts - Variable: - Concepts - Gender. - Age
- Weight
- Religion
- Income
- Concepts
Excellence
Rich
Satisfaction
Compliance
- Violence

15. Concepts … Indicator … Variable
The choice of indicators for a concept might vary with researchers, but those selected must have a logical link with the concept.

16. Concepts … Indicator … Variable
Variables
Working definition
Rich
Income
Asset
If more than ….
Knowledge
Set of questions
Total score
If more than …

17. Types of measurement scales
Three categories:
Nominal (classificatory) scale
Ordinal or ranking scale
Numerical scale

18. Types of measurement scales
Nominal (classificatory) scale: dichotomous or binary
A nominal scale enables the classification of individuals, objects or responses into subgroups based on a common/shared property or characteristic.
A variable measured on a nominal scale may have two or more subcategories depending upon the extent of variation.
The variable “gender” can be classified into two sub-categories: male and female. ‘Types of stroke’ can be classified into 3 sub-categories, outcomes (alive or dead), yes or no.
Nominal data are describe as percentage or proportion.

19. Types of measurement scales
The ordinal or ranking scale:
Besides categorizing individuals, objects, responses or a property into subgroups on the basis of common characteristic, it ranks the subgroups in a certain order.
For example, ‘income’ can be measured either quantitatively (in dollar) or qualitatively using subcategories ‘above average’, ‘average’ and ‘below average’.
The ‘distance’ between these subcategories either equal or not equal.
‘Socioeconomic status’, ‘attitude’, ‘functional outcome’ and ‘knowledge’ are variables that can be measured on ordinal scale.
Coma scale, disability scale
Likert scales

20. e.g. GLASGOW COMA SCALE
Severe, with GCS < 9
Moderate, GCS 9–12
Minor, GCS ≥ 13.

21. Types of measurement scales
Numerical scale :
Continuous scale: has values on a continuum (e.g. age:15, 17.5
Discrete scale: has values equal to integers( number of fractures, number of visits)