Scientific Research in Health: Methods, Types, and Priorities

Introduction to Scientific Research in Health

Etymology: The term “research” originates from the Latin in (on) and vestigare (find, inquire, investigate, follow traces), meaning to find or describe something. In science, research is a systematic, controlled, and critical process to discover or interpret facts, phenomena, relationships, or laws.

Research Activity: Develops or contributes to generalizable knowledge, encompassing theories, principles, information, and data collection.

Theoretical Foundations

Scientific Knowledge: Overview and basic concepts.

Conocer (Knowing): An intellectual process establishing a relationship between the knower (actor) and the known object (reality). Knowledge is acquired through recognizing an existing reality with certain features.

Knowledge Derivation:

  • Empiricism: Knowledge from random experience, without a personal research method.
  • Science: Observation, description, explanation, and prediction using logical methods.

Types of Health Research

Basic, clinical, epidemiological, and social science research.

Why Health Research?

  • To study relevant health problems and produce transferable clinical results.
  • To optimize health resource use, ensuring sustainability and equity in healthcare.
  • To serve healthy individuals and those with risk factors, extending beyond traditional clinical research.

Classification of Research

Research is classified by:

  1. Application of Results: Applied, Basic, Basic-oriented, and Development work.
  2. State of Knowledge: Exploratory, Descriptive, Explanatory, and Correlational.
Types of Investigations by Application
  • Applied Research: Addresses practical problems with direct, applicable solutions.
  • Basic Research: Seeks new knowledge without immediate practical application.
  • Basic-Oriented Research: Connects indirectly to practice, with potential future applications.
  • Development Work: Focuses on creating and refining new materials, products, or procedures.
Types of Investigations by Knowledge State
  • Exploratory Studies: Clarify and define problems in little-known areas.
  • Descriptive Studies: Build on exploratory studies to detail characteristics and relationships.
  • Explanatory Studies: Investigate cause-effect relationships through experimental (clinical trials) or analytical observational (cohort, case-control) methods.
  • Correlational Studies: Measure the degree of relationship between variables.

Types of Research by Potential Application

Applied, Basic, Basic-oriented, Development work.

Types of Research by Knowledge Status

Exploratory, descriptive, explanatory, correlational.

I. Experimental Studies

Researchers control the variable of interest and randomly assign subjects.

a) Laboratory Tests:

Controlled environment, manipulation of variables, often using animals or human cells/tissues. Example: drug dosage and side effect evaluation in animal models before human trials.

b) Controlled Clinical Trials:

Evaluate treatments or preventive measures in patients with a disease, using random assignment and blinding where possible.

c) Field Studies:

Preventive interventions in disease-free subjects, requiring large sample sizes and random assignment. Example: vitamin C for cold prevention, hepatitis B vaccine efficacy.

d) Randomized Study Groups (Clusters):

Community-based interventions, randomly assigning clusters of individuals. Example: evaluating educational programs on burns or drug use prevention.

Community Test:

Pilot studies evaluating interventions’ impact on community health.

II. Quasi-Experimental Studies

Non-random assignment of interventions. Example: fluoride supplementation in one community versus another.

III. Observational Studies

No variable manipulation, observing naturally occurring events.

a) Cross-Sectional Studies:

Prevalence studies, assessing exposure and disease simultaneously. Example: malnutrition prevalence in hospitalized children.

b) Case-Control Studies:

Comparing past exposures between individuals with (cases) and without (controls) a disease. Example: factors associated with intrauterine growth restriction.

c) Cohort Studies:

Following disease-free subjects based on exposure status, observing disease incidence over time. Example: leukemia incidence after Hiroshima bombing.

d) Screening Studies:

Identifying diseases in apparently healthy individuals using tests. Example: newborn screening for metabolic disorders, HIV testing in at-risk children.

e) Case Studies:

Describing clinical features of rare or unusual conditions. Example: congenital lobar emphysema case report.

f) Ecological Studies:

Analyzing population-level data. Example: pneumococcal mortality by region.

g) Hybrid Studies:

Combining multiple study types. Example: case-control analysis within a cohort study.

Research Design Classifications

I. Directionality
a) Prospective:

Data collected after study initiation.

b) Retrospective:

Data collected before study initiation.

c) Bi-directional:

Combination of prospective and retrospective data collection.

II. Measurement Occasions
a) Transversal:

Single measurement.

b) Longitudinal:

Multiple measurements over time.

III. Number of Samples
a) Descriptive:

Single population or sample.

b) Comparative:

Two or more populations or samples.

Priorities in Health Research

Evidence-Based Medicine, Quality of Care, Organizational Models and Service Delivery, Integration of Health Care, Prescriptions and Economic Analysis, Communication, Inequalities, and Health Promotion.

Focus of Research at Local Level

  1. Health education
  2. Environmental health
  3. Health services
  4. Nutritional status of the population
  5. Appropriate technologies and traditional medicine
  6. Perception of health disease
  7. Quality of care and satisfaction of people