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INTRODUCTION TO OPERATIONS RESEARCH
Niranjan Saggurti, PhDSenior Researcher
Scientific Development WorkshopOperations Research on GBV/HIV
AIDS 2014, Melbourne, July 22, 2014
Goal of Operations Research
• To increase the efficiency, effectiveness and quality of services delivered by providers
• To increase the availability, accessibility and acceptability of services desired by clients
• To use information collected to strengthen provision of services
Operations Research Process It involves 5 critical steps:1. Problem identification and diagnosis 2. Strategy selection 3. Strategy testing and evaluation 4. Information dissemination 5. Information utilization
Categories of Operations Research Studies • Exploratory or Diagnostic Studies
Problem isn't known
• Field Intervention Studies Program approach not known
• Evaluation Studies Impact not known
• Cost-Effectiveness Studies Cost and effectiveness not known
Steps in Operations Research
Problem Identification
• Is it an important problem? • To whom is it important?• How can the problem be addressed
by the program? • What health improvements will result
from solving this problem?
Is the Problem Researchable
• Do I need to do research to solve the problem?
• Can the problem be corrected by common sense and experience?
• Do I have enough time, money and qualified persons to do research?
• Will decision makers listen to research results?
• What ethical issues need to be considered?
Stating an OR Problem
• Describe the problem in terms of health issues facing the specified population(s)
• Describe the nature and extent of the problem
• Identify other program strategies that have been tried to solve similar problems
• Restate the problem as a question to be answered through research
Strategy to Solve the Problem
• Once an operations research problem has been identified, defined and justified a range of strategies for solving the problem can be suggested.
Choosing a Strategy to test Feasibility
• Can the program afford it?• Can it be easily implemented? • Will it be effective? • Is there enough time to test it?• Do the staff and managers want to
test it?
Research Hypotheses, Objectives and Variables
Hypotheses
• Hypotheses is a statement that specifies the expected relationship between two or more variables that can be tested through collecting information and conducting experiment
E.g. Contraceptive use will be higher in villages where the fieldworker is married than in villages where the field worker is unmarried.
Objectives
• Objectives relate to reasonable and expected contributions of the study to broad social, economic or health concerns
• An ultimate objective is that the study will provide program administrators/ mangers and policy makers with information that can be used to improve service delivery activities or reformulate policy.
Independent variables
• Programmatic factors that can be manipulated
• Strategy being tested • The “cause”
Dependent Variables
• Characteristics we expect to change • Outcomes and/ or impact being
measured • The “effect”
Types of Study Designs to Test Hypotheses
True and Quasi-Experimental Design
Quasi-Experimental Design • Does not use random assignment • Open to many threats to validity • At best, only suggestive of causality
True Experimental Design • Uses random assignment • Protects against threats to validity • Demonstrates causality
Units of Study in Operations Research
• Individuals: clients, providers, the general public
• Groups: facilities (e.g. clinics), villages, districts
Note: When unit of study is a group, the group not the individual must be used as variance measure
Symbols
= Between groups not randomly assigned
RAExperimental Group
Control Group= Random Assignment of
cases to the groups
= The passage of time
= Intervention
= Observation
= A single group of subjects
X
O
X and O in a row
- - - - - - - - - - - - - - -
Classic Experimental Design
RAExperimental Group O1 X O2
Control Group O3 O4
Time
Pretest-Posttest Non-Equivalent Control Group Design
• No random assignment
Experimental Group O1 X O2
Control Group O3 O4
Time
- - - - - - - - - - - - - -
Time Series Design
• Repeated measures on the same group over time
• No control or comparison group
ExperimentalGroup O1 O2 O3 X O4 O5 O6
Time
Non-Experimental Designs• Case StudyExperimental Group
X O1
• One Group Pre-test/Post-testExperimental Group
O1 X O2
Time
Time
Good Design to Study Integrated Services
PROGRAM XYES
PROGRAM XNO
PROGRAM YYES
X+Y Y
PROGRAM YNO
X 0
Overview of Data Collection Methods • Quantitative methods describe what
people do (e.g, how many people are using IUD). Need a lot of people for statistical analysis if the rates of usage is low.
• Qualitative methods explore why people think and behave as they do (e.g., why difficult to use IUD). Need a lot of in-depth information from few people.
Ensure Results are Used
• Plan a utilization strategy that anticipates what actions are needed to change the way services are currently implemented
• Allow sufficient time, funds and qualified persons to do a good job