Public Health Sciences

Instructions given by a patient in anticipation of the need for a medical decision. Details vary per state law. Oral advance directive: Incapacitated patient's prior oral statements commonly used as guide. Problems arise from variance in interpretation. If patient was informed, directive was specific, patient made choice, and decision was repeated over time to multiple people, then the oral directive is more valid. Written advance directive: Specific healthcare interventions that a patient anticipates he or she would accept or reject during treatment for a critical or life-threatening illness. A living will is an example. Medical power of attorney: Patient designates an agent to make medical decisions in the event that he/she loses decision-making capacity. Patient may also specify decisions in clinical situations. Can be revoked by patient if decision-making capacity is intact. More flexible than a living will. Do not resuscitate: DNR order prohibits cardiopulmonary resuscitation (CPR). Other resuscitative measures that may follow (eg, intubation) are also typically avoided.

Sexual changes:- Men – slower erection/ejaculation, longer refractory period- Women – vaginal shortening, thinning, and drynessSleep paterns: ↓ REM and slow-wave sleep; ↑ sleep onset latency; ↑ early awakenings↑ suicide rate↓ vision and hearing↓ immune response↓ renal, pulmonary and GI function↓ muscle mass, ↑ fatIntelligence does not decrease.

Primary disease prevention: Prevent disease before it occurs (eg, HPV vaccination).- Decrease disease incidence Secondary disease prevention: Screen early for and manage existing but asymptomatic disease (eg, Pap smear for cervical cancer, colonoscopy for patients age >65).- Decrease disease prevalence Tertiary disease prevention: Treatment to reduce complications from disease that is ongoing or has long-term effects (eg, chemotherapy, physical therapy for spinal injury patients, low-dose aspirin for patients with previous MI).- Prevent recurrence and slow progression Quarternary disease prevention: Identifying patients at risk of unnecessary treatment, protecting from the harm of new interventions (eg, electronic sharing of patient records to avoid duplicating recent imaging studies).

Organizational environment in which everyone can freely bring up safety concerns without fear of censure. Facilitates error identification. Event reporting systems collect data on errors for internal and external monitoring.

Forcing functions (those that prevent undesirable actions [eg, connecting feeding syringe to IV tubing]) are the most effective. Standardization improves process reliability (eg, clinical pathways, guidelines, checklists). Simplification reduces wasteful activities (eg, consolidating electronic medical records). Deficient designs hinder workflow and lead to staff workarounds that bypass safety features (eg, patient ID barcodes affixed to computers due to unreadable wristbands).

Process improvement model to test changes in real clinical setting. Impact on patients:- Plan – define problem and solution- Do – test new process- Study – measure and analyze data- Act – integrate new process into regular workflow

Structural: Physical equipment, resources, facilities- Example: Number of diabetes educators Process: Performance of system as planned- Example: Percentage of diabetic patients whose HbA1c was measured in the past 6 months Outcome: Impact on patients- Example: Average HbA1c of patients with diabetes Balancing: Impact on other systems/outcomes- Example: Incidence of hypoglycemia among patients who tried an intervention to lower HbA1c

Focuses on systems and conditions rather than an individual's error. The risk of a threat becoming a reality is mitigated by differing layers and types of defenses. Patient harm can occur despite multiple safeguards when "the holes in the cheese line up."

May involve patient identification, diagnosis, monitoring, nosocomial infection, medications, procedures, devices, documentation, handoffs. Medical errors should be disclosed to patients, independent of immediate outcome (harmful or not). Active error: Occurs at level of frontline operator (eg, wrong IV pump dose programmed). Immediate impact. Latent error: Occurs in processes indirect from operator but impacts patient care (eg, different types of IV pumps used within same hospital). Accident waiting to happen.

Root cause analysis: Retrospective approach. Applied after failure event to prevent recurrence.- Uses records and participant interviews to identify all the underlying problems (eg, process, people, environment, equipment, materials, management) that led to an error. Failure mode and effects analysis: Forward-looking approach. Applied before process implementation to prevent failure occurence.- Uses inductive reasoning to identify all the ways a process might fail and prioritizes them by their probability of occurrence and impact on patients.

<1 year: Congenital malformations > Preterm birth > SIDS 1-14 years: Unintentional injury > Cancer > Congenital malformations 15-34 years: Unintentional injury > Suicide > Homicide 35-44 years: Unintentional injury > Cancer > Heart disease 45-64 years: Cancer > Heart disease > Unintentional injury 65+ years: Heart disease > Cancer > Chronic respiratory disease

Defined as readmission for any reason within 30 days of discharge from original admission.Readmissions may be reduced by discharge planning and outpatient follow-up appointments. Medicare: Congestive HF > Septicemia > Pneuonia Medicaid: Mood disorders > Schizophrenia/psychotic disorders > Diabetes mellitus with complications Private insurance: Maintenance of chemotherapy or radiotherapy > Mood disorders > Complications of surgical procedures or medical care Uninsured: Mood disorders > Alcohol-related disorders > Diabetes mellitus with complications

The effect of exposure to risk factors may depend on the duration and intensity of the exposure; long-term exposure may be necessary well before an effect on the disease process is clinically evident (eg, lung cancer devloping after decades of smoking exposure).

Unit of analysis is populations, not individuals. The frequency of a given characteristic (eg, vitamin D intake) and a given outcome (eg, multiple sclerosis) are studied using population data. Ecological studies are useful to generate hypotheses but should not be used to make conclusions regarding individuals within these populations (ecological fallacy).

Measure of the severity of a disease or conidition. It is defined as the proportion of reported cases of a specific disease or condition that are fatal within the population affected by the disease or condition over a specific time. CFR can be calculated as the number of fatal cases of disease/condition divided by the total number of people with the disease/condition.

Method used to predict the probability of a binary outcome (eg, the presence or absence of gastric cancer) based on 1 or more independent variables that can be either continuous or categorical. For example, a test used to predict the probability of gastric cancer based on alcohol consumption, tobacco use, and charred food consumption.

Stratified analysis

A third variable that positively or negatively influences a study outcome; occurs when the exposure has different effect between groups.Not considered a bias in itself. Example: A certain drug works in children, but does not have any effect in adults. Solution: Stratified analysis. When the popuation is stratified according to the factor, different results will be seen.

Total number of new cases (in an initially disease-free population) over a specific period divided by the number of people at risk at the beginning of the period. Does not account for deaths in the period under study because the people who died were, at some point during the intervening period, still considered part of the baseline population at risk for the disease.

The percentage of incidence of disease among exposed individuals that can be attributed to the exposure. (RR-1)/RR AR/incidence of disease in exposed group x 100

An unexpected occurence involving death or serious physical or psychological injury (eg, inpatient suicide, death of a full-term infant, retained object after surgery, wrong patient/side/procedure) that requires immediate investigation.