220905P - IDENTIFYING HEALTH PROBLEMS AND CHOOSING RESEARCH PRIORITIES

Presentation at a workshop on Research Methodology in Health Sciences held at the Northern Area Armed Forces Hospital on 5 September 2022. By Professor Omar Hasan Kasule Sr. MB ChB (MUK). MPH (Harvard), DrPH (Harvard)

1.0 IDENTIFYING HEALTH PROBLEMS BY MEASUREMENT OF DISEASE INCIDENCE

• New disease is measured by incidence.
• Incidence rate (IR) = incident number/ total person-time.
• Cumulative incidence = incident number / susceptible population at the start.

2.0 IDENTIFYING HEALTH PROBLEMS BY MEASUREMENT OF DISEASE PREVALENCE

• Existing disease is measured by prevalence.
• Prevalence proportion = # cases of illness at a particular time (old and new) / # of individuals in the population at the same time.
• Prevalence can be point, period, and lifetime prevalence.
• Prevalence proportion = incidence rate x average duration of disease.
• Prevalence is useful for administrative purposes.
• Prevalence is not used for etiological studies because the time sequence is not obvious. Prevalence changes due to changes in incidence and duration.

3.0 IDENTIFYING HEALTH PROBLEMS BY MEASURING EXCESS DISEASE (ODDS RATIO)

• OR up to 0.3 = strong benefit,
• OR 0.4 – 0.5 = moderate benefit,
• OR 0.6 – 0.8 = weak benefit,
• OR 0.9 – 1.1 = no effect,
• OR 1.2 –1.6 = weak hazard,
• OR 1.7 –2.5 = moderate hazard,
• OR >=2.6 = strong hazard.

 

4.0 IDENTIFYING HEALTH PROBLEMS BY MEASURING DISEASE IMPACT

• Life expectancy at birth.
• A common measure of disease impact is the years of potential life lost (YPLL).
• YPLL is the number of years a person would have lived if he did not die prematurely
• Premature death is generally considered below 65 years.
• QUALITY ADJUSTED LIFE YEAR (QUALY) is a generic measure of disease burden combining quantity and quality of life. I QUALY = 1 year in perfect health
• DISABILITY ADJUSTED LIFE YEARS (DALY) is an overall measure of overall disease burden. 1 DALY = loss of the equivalent of one year of full health.

5.0 DETERMINING RESEARCH PRIORITIES BY ASKING VITAL QUESTIONS

• Does a health problem exist?: Is there a gap between the actual and the ideal? Are the reasons for the gap not clear? Is potentially more than one solution possible?
• What information needed to define a research question?: 1. Information on present health status 2. Information to evaluate on-going interventions 3. information to define problems.
• What criteria used to prioritize among research questions: 1. relevance 2. urgency 3. political acceptability 4. feasibility of study 7. applicability of results 8. ethical acceptability

6.0 SELECTING RESEARCH PRIORITIES BY THE NOMINAL GROUP TECHNIQUE 1 - PROCESS

• Individuals list their ideas on paper,
• Lists are displayed and are grouped,
• Voting and ranking,
• Scoring and re-discussion,
• Second vote and re-ranking

7.0 SELECTING RESEARCH PRIORITIES BY THE NOMINAL GROUP TECHNIQUE 2 - ADVANTAGES

• Separation of discussion from voting,
• Voting is anonymous,
• Results indicate input from all members,
• Voting aggregates individual judgments

8.0 STEPS IN HEALTH PROBLEM ANALYSIS

• Obtaining views of managers and health care workers.
• Specification of the core problem(s).
• Triangulation, looking at a problem from various angles.
• Listing factors of the problem, the relation between the problem and the factors and the interrelations among factors.
• Grouping factors as: socio-cultural, economic, service related, disease related. 6. Constructing a problem analysis diagram.

9.0 STATING THE HEALTH PROBLEM

• Socio-cultural and economic background to the problem.
• Health status assessment.
• Nature of the problem: how, who, when, where, how.
• Solutions tried in the past.
• Justification for new research.
• Type of information needed.
• Definition of crucial terms and concepts.

10.0 FORMULATION OF RESEARCH OBJECTIVES

• Types of research objectives: 1. general 2. specific.
• Advantages of stating research objectives: 1. focusing the study 2. avoiding unnecessary data collection 3. organizing the study in parts/phases.
• Guidelines for writing objectives: 1. coherent and in logical sequence 2. in operational terms 3. realistic 4. action verbs.
• Research title: 1. must be concise 2.  must reflect objectives.

11.0 RESEARCH HYPOTHESES

• Types of hypotheses: 1. null hypothesis 2. alternative hypothesis.
• Hypotheses based on causal relations.
• Criteria of causality (sababiyyat) by Bradford Hill: strength of association, consistency, specificity, temporarily, biological gradient, plausibility,  coherence, experiment, analogy).
• Advantage of hypothesis-based research: 1. Research based on hypotheses is more powerful than research based only on stating problems. 2. avoiding fishing trip findings.