Table 1.

Core variables collected at baseline and follow-up in the Health and Prevention Enhancement study from 2003 to 2014

Item	List
Self-record questionnaires	Demographic and lifestyles questionnaire: socioeconomic variables, including education, household income, marital status and occupation; medical history of diabetes, hypertension, dyslipidaemia and cancer; family history of diabetes, hypertension, dyslipidaemia and cancer in first relatives; alcohol consumption and cigarette smoking Physical activity: Korea-validated version of the International Physical Activity Questionnaire short form Dietary factors: Mini-Dietary Assessment Index Sex-specific questionnaire: International Prostate Symptom Score and the International Index of Erectile Function for men; reproductive factors for women, including menstrual history (age at menarche, length and regularity of menstrual cycle), menopausal status and age, pregnancy history (including the number/methods of pregnancies and abortions) and breast feeding Psychiatric assessment questionnaire: Beck Depression Inventory and Quick Inventory of Depressive Symptomatology-Self Report
Anthropometric measurements and physical examination	Systolic and diastolic blood pressure Height, weight and waist circumference Body composition using a multifrequency bioimpedance analyser Physical examination by physician Eye examination, including visual acuity, ocular tonometry and slit-lamp test by ophthalmologist Fundus photography (persons≥35 years) by ophthalmologist Hearing test (persons≥50 years) by otolaryngologist
Laboratory blood tests	Complete blood cell count (WBC, RBC and platelet count, haemoglobin, haematocrit) Coagulation profiles (PT, PT-INR, aPTT) Diabetes profiles (fasting glucose, haemoglobin A1c) Liver function profiles (protein/albumin, AST/ALT/gamma-GTP, total bilirubin) Kidney function profiles (BUN, creatinine) Electrolytes (calcium, phosphate, sodium, potassium, chloride, total CO2) Lipid profiles (total cholesterol, triglycerides, LDL/HDL cholesterol levels) Uric acid
Urine tests	Protein, glucose, ketone, bilirubin, blood and pH
Stool exams	Occult blood in stool, parasite assay
Infections and inflammation markers	HBsAg, anti-HBs, anti-HCV HAV Ab IgG (persons<50 years) Helicobacter pylori IgG Ab	VDRL (Rapid Plasma Reagin Card Test) HIV Ag/Ab combo test Hs-CRP
Hormones	Thyroid function tests (TSH, T3, total-T4, free-T4)
Tumour markers	AFP, CEA CA19-9	CA-125 (all females) PSA (men≥35 years)
Other clinical tests	Chest X-ray (digital imaging) Pulmonary function test ECG Gastroendoscopy with pathological reports	Pap smear and gynaecological examination (women≥35 years) Mammography (women≥35 years)

AFP, alpha-fetoprotein; ALT, alanine transaminase; anti-HBs, anti-hepatitis B surface antibody; anti-HCV, anti-hepatitis C antibody; aPTT, activated partial thromboplastin time; AST, aspartate transaminase; BUN, blood urea nitrogen; CA-125, cancer antigen 125; CA19-9, cancer antigen 19-9; CEA, carcinoembryonic antigen; GTP, gamma-glutamyl transferase; HBsAg, hepatitis B surface antigen; Helicobacter pylori IgG Ab, hepatitis A IgG antibody; HDL, high-density lipid; Hs-CRP, high-sensitivity C reactive protein; INR, International Normalized Ratio; LDL, low-density lipid; PSA, prostate-specific antigen; PT, prothrombin time; RBC, red blood cell; TSH, thyroid-stimulating hormone; VDRL, venereal disease research laboratory; WBC, white blood cell.