I. Key Factors Affecting Blood Test Accuracy

1. Dietary Factors:

Do not change your dietary habits before blood sampling and refrain from alcohol for 24 hours. Fasting (at least 8 hours, ideally 12-14 hours, but no more than 16 hours) is required for tests including, but not limited to, fasting blood glucose, fasting insulin, fasting C-peptide, lipid profile, blood viscosity, bone metabolism markers, and platelet aggregation.

2. Physiological Changes

Avoid strenuous exercise 24 hours prior to blood sampling. On the day of the test, remain calm and rest for at least 5 minutes prior to sampling. If post-exercise sampling is required, follow the physician’s instructions and inform the laboratory personnel.

II. Urine Testing Guidelines 

1. Collection Requirements for Urine Specimens

(1) For Routine Urinalysis, Urine HCG, and Chyluria Testing

Cleanse the external genitalia and collect a fresh midstream urine sample, preferably 5–10 mL from the first morning void. Ensure the sample is free from contamination by menstrual blood, vaginal discharge, semen, or feces, and deliver it for testing within 2 hours.

(2) For Urine Culture

Female Patients: Cleanse the vulva with soapy water followed by a rinse with sterile water, wipe with a sterile gauze, and, using a finger to separate the labia, collect 5–7 mL of midstream urine in a sterile container.  

Male Patients: Retract the foreskin, clean the urethral orifice with soapy water, rinse with clean water, and collect 5–7 mL of midstream urine in a sterile container.  

Deliver the sample promptly for testing.

(3) 24-Hour Urine Collection

For tests such as endogenous creatinine clearance, quantitative urine glucose, protein, creatinine, creatine, and electrolyte measurements, a 24-hour urine collection is required.

Collect all urine over a 24-hour period, accurately record the total volume on the requisition form, mix the specimen thoroughly, then transfer 10 mL into a clean, dry container and deliver it.

2. Stool Sample Testing Guidelines

(1) For Routine Stool Analysis, Occult Blood, and Parasitic Examinations

Collect a fresh stool sample approximately the size of a fingertip (around 5 g), preferably containing purulent, bloody, or mucous components and place it in a clean, dry, non-absorbent container with a lid. Deliver it for testing within 1 hour.

(2) For Stool Culture

Natural defecation collection: After natural bowel movement, select 2–3 g from the purulent, bloody, or mucous portions, or 2–3 mL of the liquid component, and place it in a sterile container. Record the collection time and deliver promptly.

Rectal Swab: Moisten a sterile cotton swab with saline, insert it 4–5 cm into the anus, gently rotate, then place it in a sterile tube for immediate testing.

3. Collection of Other Body Fluid Specimens

(1) Sputum

For routine sputum analysis, the first sputum of the morning is ideal. Patients should rinse their mouth with water and cough deeply from the lower respiratory tract. Record the collection time and send the sample promptly.  

For sputum culture, rinse with sterile water before coughing into a sterile container and send the sample immediately.

(2) Prostate Specimens

 Routine examination: A sample is collected by a physician, smeared onto a slide, and sent for testing immediately.  

 Culture: Collect the specimen under sterile conditions, place it in a sterile tube, and deliver it promptly.

(3) Cerebrospinal Fluid (CSF): Collected via lumbar puncture by a physician into three separate tubes for immediate testing.

(4) Vaginal Discharge Specimen: Collected by an obstetrician/gynecologist, typically from the vagina, posterior fornix, or cervical os, placed in a sterile tube and delivered promptly.

(5) Other Male Urogenital Specimens:

Collected by a physician, primarily using swabs from the urogenital tract; in select cases, prostatic fluid or semen may be obtained.

(6) Pus for Fluid Cultures

Collected under sterile conditions by a physician, placed in a sterile tube, and delivered immediately.