100+ Free Public Health Assistant Practitioner (China) Practice Questions

Basic Epidemiology and Medical Statistics (流行病学与卫生统计学基础)

Comprehensive knowledge of epidemiological research designs, biostatistical analysis, and screening methodology: (1) Epidemiological Study Designs: Observational descriptive studies (cross-sectional surveys, ecological studies), analytical studies (case-control design, odds ratio OR calculation, matching; cohort study design, relative risk RR, attributable risk AR, population attributable risk PAR, prospective vs retrospective cohorts), experimental studies (randomized controlled trials RCT, field trials, community trials, blinding, intention-to-treat); (2) Measures of Disease Frequency & Health Indicators: Incidence rate, attack rate, secondary attack rate (SAR), prevalence rate (point vs period), cumulative incidence, mortality rate, cause-specific mortality, case fatality rate, infant mortality rate, standardization of rates (direct vs indirect method); (3) Causal Inference and Bias Control: Hill's causal criteria (temporal relationship, strength, biological plausibility, consistency), systematic errors (selection bias: Berkson's bias, healthy worker effect, non-response bias; information bias: recall bias, interviewer bias, misclassification; confounding bias and control via matching, restriction, stratification, multivariate modeling); (4) Screening and Diagnostic Tests: Sensitivity, specificity, false positive rate (alpha), false negative rate (beta), positive predictive value (PPV), negative predictive value (NPV), Youden index, parallel testing vs serial testing; (5) Biostatistical Fundamentals: Types of statistical data (quantitative/numerical, categorical/nominal, ordinal/ranked), measures of central tendency (arithmetic mean, geometric mean, median), measures of dispersion (range, interquartile range, variance, standard deviation, coefficient of variation), normal distribution properties (standard normal transformation Z-score, 95% and 99% reference intervals), sampling error and standard error of the mean (SEM), parameter estimation (95% confidence intervals), hypothesis testing logic (Type I error alpha, Type II error beta, test power 1-beta, P-value interpretation), Student's t-test (one-sample, paired-samples, two independent samples), Chi-square test (2x2 contingency table, continuous correction, Fisher's exact test, R×C table), non-parametric rank-sum tests (Wilcoxon signed-rank, Mann-Whitney U), linear correlation (Pearson r vs Spearman rank correlation), and statistical table/graph presentation.

Environmental and Occupational Hygiene Basics (环境卫生学与职业卫生学基础)

Environmental and workplace health determinants, toxicant mechanisms, exposure standards, and clinical pathology: (1) Atmospheric Hygiene: Structure of atmosphere, major air pollutants (particulate matter PM2.5, PM10, sulfur dioxide SO2, nitrogen oxides NOx, carbon monoxide, ground-level ozone), acute pollution episodes (London smog, photochemical smog), chronic health impacts (respiratory illness, cardiovascular mortality, lung cancer), indoor air pollutants (formaldehyde, volatile organic compounds VOCs, benzene, radon, environmental tobacco smoke), air quality standards; (2) Drinking Water Sanitation: Water resources (groundwater vs surface water), biological and chemical water contaminants, waterborne infectious diseases, endemic fluorosis (mottled enamel, skeletal fluorosis), endemic arsenism, water purification and treatment train (coagulation-flocculation, sedimentation, sand filtration, disinfection via chlorination/chloramine/UV/ozone), chlorine demand and residual chlorine (free vs combined), disinfection byproducts (trihalomethanes THMs, haloacetic acids), Standards for Drinking Water Quality (GB 5749); (3) Soil and Solid Waste Hygiene: Soil contamination pathways, sanitary landfill, incineration, hazardous waste disposal, composting, endemic goiter and iodine deficiency disorders (IDD); (4) Occupational Hygiene and Industrial Toxicology: Occupational health limits (Maximum Allowable Concentration MAC, Permissible Concentration-Time Weighted Average PC-TWA, Permissible Concentration-Short Term Exposure Limit PC-STEL), industrial dust hazards, pneumoconiosis pathogenesis, silicosis (free silica content, nodular vs diffuse fibrosis, radiographic eggshell hilar calcification, tuberculosis complication), coal workers' pneumoconiosis, asbestosis (pleural plaques, mesothelioma risk); (5) Chemical Toxicants in Industry: Lead poisoning (inhibition of ALAD/ferrochelatase, basophilic stippling of RBCs, lead line on gums, wrist drop, EDTA chelation therapy), Mercury poisoning (tremor, erethism, stomatitis, Minamata disease, dimercaptosuccinic acid DMSA treatment), Cadmium poisoning (itai-itai disease, renal proximal tubular proteinuria), Benzene toxicity (bone marrow aplasia, aplastic anemia, acute myeloid leukemia AML), Organic solvents (toluene, xylene, carbon tetrachloride hepatotoxicity), Asphyxiating gases (chemical: carbon monoxide and carboxyhemoglobin, hydrogen cyanide and cytochrome oxidase inhibition, hydrogen sulfide; simple: nitrogen, CO2, methane), Pesticide poisoning (organophosphate cholinesterase inhibition, muscarinic/nicotinic/CNS signs, atropine and pralidoxime oxime reactivation); (6) Physical Hazards and Ergonomics: Heat illness (heat cramps, heat exhaustion, heat stroke/hyperthermia, wet bulb globe temperature WBGT), occupational noise (temporary vs permanent threshold shift, 4000 Hz notch on audiogram), vibration disease (Raynaud's phenomenon / white finger disease), ionizing radiation (acute radiation sickness, deterministic vs stochastic effects), non-ionizing radiation (UV keratitis/snow blindness, microwave cataracts), and occupational health surveillance protocols.

Food Hygiene and Nutrition (营养与食品卫生学)

Nutritional biochemistry, clinical deficiency states, dietary recommendations, and foodborne toxicology: (1) Human Nutrition Fundamentals: Energy balance and Basal Metabolic Rate (BMR); Dietary proteins (essential amino acids, protein biological value BV, protein digestibility-corrected amino acid score, nitrogen balance, Kwashiorkor vs Marasmus); Dietary lipids (essential fatty acids linoleic/alpha-linolenic, saturated vs monounsaturated vs polyunsaturated fatty acids, trans fatty acids, cholesterol); Dietary carbohydrates and dietary fiber (soluble vs insoluble fiber benefits); (2) Vitamins and Minerals: Fat-soluble vitamins—Vitamin A (retinol, night blindness, xerophthalmia, Bitot's spots), Vitamin D (cholecalciferol, 1,25-(OH)2-D3, rickets, osteomalacia), Vitamin E (alpha-tocopherol antioxidant), Vitamin K (clotting factor synthesis); Water-soluble vitamins—Thiamine / Vitamin B1 (beriberi: dry, wet, Wernicke-Korsakoff), Riboflavin / Vitamin B2 (angular stomatitis, cheilosis, glossitis, scrotal dermatitis), Niacin / Vitamin B3 (pellagra 3Ds: dermatitis, diarrhea, dementia), Vitamin B6 (pyridoxine), Folate (megaloblastic anemia, neural tube defects), Vitamin B12 (cobalamin, pernicious anemia, intrinsic factor), Vitamin C (ascorbic acid, scurvy, collagen hydroxylation); Major and trace minerals: Calcium (peak bone mass, osteoporosis), Phosphorus, Iron (heme vs non-heme, iron deficiency anemia, transferrin saturation), Iodine (thyroid hormones, goiter, congenital hypothyroidism / cretinism), Zinc (taste acuity, growth stunting, acrodermatitis enteropathica), Selenium (Keshan disease cardiomyopathy, Kashin-Beck disease osteochondropathy); (3) Dietary Guidelines and Nutritional Assessment: Chinese Dietary Guidelines (中国居民膳食指南) and Balanced Diet Pagoda (平衡膳食宝塔); Dietary Reference Intakes (DRIs: EAR, RNI, AI, UL); Nutritional status assessment (dietary recall, anthropometry BMI, biochemical biomarkers, clinical deficiency signs); Special group nutrition (infancy, breastfeeding, pregnancy energy/iron/folate needs, elderly sarcopenia); (4) Food Contamination: Biological contaminants (mold mycotoxins: Aflatoxin B1 hepatocarcinogenicity and Aspergillus flavus, Ochratoxin A nephrotoxicity, Zearalenone estrogenic effect); Chemical contaminants (N-nitroso compounds, polycyclic aromatic hydrocarbons BaP from charbroiling, heterocyclic amines, acrylamide from high-heat starch frying, heavy metals Pb/Cd/Hg, pesticide/veterinary residues); Food additives (preservatives, antioxidants, colorants, nitrite limits in cured meats); (5) Food Poisoning and Outbreak Investigation: Diagnostic criteria of food poisoning; Bacterial food poisoning: Salmonella (enteritis, eggs/poultry), Vibrio parahaemolyticus (halophilic marine seafood, watery/bloody diarrhea), Staphylococcus aureus (heat-stable enterotoxin, rapid 1–6 hour onset, vomiting), Clostridium botulinum (neurotoxin, canned foods/fermented beans, cranial nerve palsies, flaccid paralysis), Bacillus cereus (emetic vs diarrheal toxins), Escherichia coli (EHEC O157:H7 hemolytic uremic syndrome HUS); Chemical food poisoning: Nitrite toxicosis (methemoglobinemia, cyanosis, methylene blue antidote), Organophosphate pesticide residues; Toxic animal and plant food poisoning: Pufferfish poisoning (tetrodotoxin, voltage-gated Na+ channel blockade, rapid respiratory arrest), Wild mushroom toxins (amatoxins/phallotoxins Amanita phalloides liver necrosis, muscarine parasympathetic overdrive), Sprouted potato (solanine alkaloid), Raw kidney beans (phytohemagglutinin destroyed by thorough boiling), Ginko seed (ginkgotoxin), Bitter almonds (amygdalin and cyanide release); Emergency epidemiological investigation of food poisoning outbreaks (case definitions, line listings, attack rate calculation, food-specific attack rate, culprit food identification, sample collection, and administrative reporting).

Disease Control, Immunization, and Health Education (疾病预防控制、免疫规划与健康教育)

Infectious disease surveillance, outbreak containment, vaccine epidemiology, chronic disease management, and behavioral health promotion: (1) Communicable Disease Epidemiology: The epidemic process triad (Source of infection: human cases, carriers, animal reservoirs/zoonoses; Transmission routes: respiratory droplets, airborne droplet nuclei, fecal-oral, waterborne, foodborne, vector-borne, contact, bloodborne, vertical perinatal; Susceptible population and herd immunity threshold); Epidemic intensity patterns (sporadic, endemic, outbreak, epidemic, pandemic); (2) Prevention and Control Measures: Three-tiered disease prevention strategy (Primary prevention: health promotion, vaccination, sanitation, environmental engineering; Secondary prevention: early detection, early diagnosis, early treatment, early isolation, early reporting; Tertiary prevention: clinical rehabilitation, disability limitation, complication prevention); Containment measures against source (isolation, treatment), routes (disinfection: concurrent vs terminal, vector control), and susceptible contacts (emergency vaccination, post-exposure chemoprophylaxis, medical quarantine observation period); (3) Statutory Infectious Disease Framework: Law of the PRC on Prevention and Treatment of Infectious Diseases (传染病防治法); Classification system—Class A (甲类: Plague 鼠疫, Cholera 霍乱; mandatory 2-hour web direct reporting, strict isolation of patients/carriers and quarantine of contacts), Class B (乙类: SARS, AIDS, viral hepatitis, polio, rabies, tuberculosis, dengue, etc.; standard 24-hour web reporting; Class B managed under Class A protocols when designated), Class C (丙类: influenza, mumps, rubella, hand-foot-and-mouth disease, acute infectious diarrhea; 24-hour reporting); Public Health Emergency Regulations; (4) National Immunization Program (NIP / 扩大国家免疫规划): Vaccine classifications (Program vaccines / Category 1 vs Non-program vaccines / Category 2); Cold chain logistics (refrigerators 2–8°C, freezer -20°C for OPV, cold boxes, temperature monitoring devices); Routine pediatric schedule: Hepatitis B vaccine (HepB: 0, 1, 6 months), BCG vaccine (tuberculosis, at birth), Poliovirus vaccine (IPV/OPV sequence), DTaP (diphtheria-tetanus-pertussis combined at 3, 4, 5, 18 months), Measles-Rubella/MMR (measles-mumps-rubella at 8 months and 18 months), Japanese encephalitis vaccine (live attenuated JEV-L), Group A and Group A+C Meningococcal polysaccharide vaccines (MPSV), Hepatitis A vaccine (HepA-L); Contraindications to vaccination (absolute: severe anaphylaxis to prior dose, acute severe febrile illness, encephalopathy; relative/temporary contraindications); Adverse Events Following Immunization (AEFI): classification (common minor vaccine reactions: fever, local erythema/induration; abnormal vaccine reactions / rare severe complications: anaphylactic shock, Henoch-Schonlein purpura, thrombocytopenia; programmatic/injection errors; coincidental events; psychogenic mass reactions); AEFI reporting, emergency management of anaphylaxis (intramuscular epinephrine 1:1000), and investigation procedures; (5) Chronic Non-Communicable Disease (NCD) Prevention: Epidemiological transition, risk factors (tobacco smoking, physical inactivity, unhealthy diet, harmful alcohol use), national basic public health service package (国家基本公共卫生服务规范) for Hypertension management (screening, 3-tier classification, quarterly follow-up, blood pressure targets <140/90 mmHg) and Type 2 Diabetes management (fasting plasma glucose screening, lifestyle counseling, quarterly glycemic monitoring, referral indications); Stroke and coronary heart disease risk stratification; Cancer screening strategies (cervical cancer HPV/Pap smear, breast cancer mammography/ultrasound, colorectal cancer FOBT/colonoscopy); (6) Health Education and Health Promotion: Principles of health communication (sender, message, channel, receiver, feedback); Behavioral change theories: KABP / KAP Model (Knowledge is the basis, Attitude/Belief is the driving force, Practice/Behavior is the goal), Health Belief Model (HBM: perceived susceptibility, perceived severity, perceived benefits, perceived barriers, cues to action, self-efficacy), Stages of Change / Transtheoretical Model (TTM: precontemplation, contemplation, preparation, action, maintenance, termination/relapse), Theory of Planned Behavior (TPB); Health promotion strategy (Ottawa Charter 5 action areas: build healthy public policy, create supportive environments, strengthen community action, develop personal skills, reorient health services); Evaluation of health education programs (formative, process, impact, and outcome evaluation).