EPB - Ch. 1

Risk analysis definition

Multidisciplinary public health field involving risk assessment, communication, and management to define health risks from biologic, chemical, thermal, or mechanical hazards

Four components of risk assessment

Hazard identification, dose-response assessment, exposure assessment, risk characterization

Hazard definition

Any agent (biologic, chemical, thermal, mechanical, psychosocial) with potential to cause harm — cannot cause harm without human interaction

Hazard identification

Determines whether an agent actually causes adverse effects on biologic tissue using laboratory and field studies

Dose-response assessment

Determines the relationship between amount of hazard at target tissues/organs and levels of response (illness, mortality, fitness, body weight)

LD₅₀ vs ED₅₀

LD₅₀ is the lethal dose causing mortality in 50% of subjects; ED₅₀ is the exposure dose causing illness in 50% of subjects

Confidence band in dose-response curves

Indicates precision/reliability of estimates — widest at very low and very high doses, where accuracy is most compromised

Limitations of animal-to-human generalizability

Differences in dose delivery method, posture, similarity of animal to human system, and human heterogeneity of response

Heterogeneity of response

Variation in human biologic response to uniform exposure due to age, sex, body mass, disease status, and hydration status

Exposure assessment

Determines the level of a hazard experienced by a population; accounts for source of exposure, level of exposure, and how it is absorbed by the body

Key shift in exposure assessment methods

From self-reported assessments to objective monitors (air monitors, physical activity monitors, biomarkers like urinary cotinine and blood alcohol)

Risk characterization

Final step of risk assessment; involves one or more estimates of the association between a given exposure and likelihood of a disease outcome

Forms of risk estimates (least to most valid)

Correlation coefficient (least valid), regression estimate, simple proportion, relative risk — always accompanied by confidence intervals or bands

Risk communication definition

Quantifying and characterizing the likelihood that a hazard will cause harm in terms meaningful to the public

Micromort

A 1

Highest daily risk of death by micromort

Car crash and police duty accumulate a 1

Key factors in public risk perception

Choice and control — people tolerate risks they choose (driving) but fear risks they cannot control (flying), even when statistically safer

Health communication definition

Use of communication strategies to inform and influence individual and community decisions that promote health and prevent disease

Health literacy definition

How well individuals understand health communication messages in order to make appropriate health decisions

Three types of health literacy (2003 National Assessment)

Clinical type (patient-provider interaction), prevention type (maintaining health behaviors), navigation type (understanding healthcare system/insurance)

Additional health literacy components

Numeracy (working with numbers), computer/e-health literacy (accessing health info online), media literacy (critically analyzing media health messages)

Three public health uses of health communication

Prevention, risk communication, and crisis communication (e.g., disease outbreaks, natural disasters)

Social/health marketing definition

CDC-developed customer-centered, science-based approach to developing and implementing health campaigns for targeted audiences

Communication strategy

A planned document expressing the components needed for an effective campaign — includes target audiences, channels, key images, intended actions, and audience benefits

Risk management definition

Strategies taken to eliminate risks or lower them to acceptable levels, often determined by a government agency with scientific and public input

Six examples of risk management

Making recommendations, regulatory development, licensing laws, standard setting, control measures, monitoring and surveillance

Statistical threshold for "TRUE" risk in public health science

P-value below 0.05 with statistical power of beta ≥ 0.80

Tension in risk management decision-making

Must balance sound science (requiring statistical significance) with timely public health practice (requiring decisions with limited evidence)

Cost-benefit considerations in risk management

Must weigh scientific data, resource availability, and social/political/economic consequences of taking or not taking action

Why conduct risk analysis

To determine health and disease effects from different exposures, compare new vs. existing technologies, set risk management priorities, and build public consensus on safety