OCN Practice Questions (2026) — Free Sample Questions with Answers

Answer: A

Annual low-dose CT of the chest: Correct. USPSTF (2021) recommends annual low-dose CT for adults 50–80 with at least 20 pack-years who currently smoke or quit within the past 15 years; he meets all criteria.

Annual chest radiograph with sputum cytology: Chest x-ray and sputum cytology did not reduce lung cancer mortality in screening trials and are not recommended for screening.

No screening, because he no longer smokes: Former smokers remain eligible until 15 years after quitting; he quit only 8 years ago.

Serum CEA level measured every 6 months: Tumor markers such as CEA are not sensitive or specific enough for lung cancer screening in asymptomatic adults.

Lung cancer screening = annual LDCT for ages 50–80, ≥20 pack-years, and current smoking or quitting within 15 years.

Answer: D

Compare the new agent with standard therapy in randomized groups: Randomized comparison with the standard of care is the purpose of a phase III trial.

Measure the tumor response rate in one specific cancer type: Estimating efficacy (response rate) in a defined disease is the main aim of phase II.

Track rare and long-term effects after FDA approval of the drug: Post-marketing surveillance after approval is phase IV.

Find a safe dose and schedule and the dose-limiting toxicities: Correct. Phase I trials establish safety, the maximum tolerated or recommended dose, schedule and pharmacokinetics.

Phase I = safety and dose; II = efficacy/response; III = randomized comparison with standard; IV = post-approval surveillance.

Answer: C

175 mg: This is the per-square-meter dose without multiplying by the patient's BSA.

700 mg: This results from using 4.0 (height × weight ÷ 3,600) without taking the square root, doubling the dose.

350 mg: Correct. 180 × 80 = 14,400; 14,400 ÷ 3,600 = 4; √4 = 2.0 m²; 175 mg/m² × 2.0 m² = 350 mg.

87.5 mg: This divides the dose by the BSA instead of multiplying, giving half the intended dose.

Dose = mg/m² × BSA; Mosteller BSA = √(cm × kg ÷ 3,600). Independent double checks of BSA and dose are required before administration.

Answer: D

Constipation will fade within 1–2 weeks as tolerance develops: Tolerance develops to sedation and nausea, but not to opioid-induced constipation.

Take a bulk fiber supplement daily with small amounts of fluid: Bulk-forming fiber without adequate fluid can worsen constipation or cause impaction in patients on opioids.

Wait until 5 days without a stool before using any laxative: Waiting allows severe constipation to develop; prevention should begin with the opioid.

Take a scheduled stimulant laxative while you take opioids: Correct. Opioid-induced constipation persists for the duration of therapy, so a prophylactic stimulant laxative (e.g., senna) is started with the opioid.

Every scheduled opioid needs a scheduled bowel regimen: no tolerance develops to constipation.

Answer: A

High potassium, high phosphorus, low calcium, high uric acid: Correct. Rapid cell lysis releases potassium, phosphate and nucleic acids (uric acid); phosphate binds calcium, causing hypocalcemia.

Low potassium, low phosphorus, high calcium, low uric acid: This is the reverse of TLS; high calcium with low phosphorus suggests hypercalcemia of malignancy instead.

High sodium, low potassium, high calcium, normal uric acid: Hypernatremia and hypokalemia are not features of TLS, which causes hyperkalemia.

Low sodium, low serum osmolality, concentrated urine: Dilutional hyponatremia with concentrated urine describes SIADH, not TLS.

TLS = 'K-P-U up, Ca down': hyperkalemia, hyperphosphatemia, hyperuricemia, hypocalcemia, risking AKI and dysrhythmias.

Answer: C

"Many people feel that way. Let's focus on your pain plan today.": This normalizes and redirects without assessing suicide risk, missing a possible warning sign.

"You shouldn't talk like that; your family needs you.": This is judgmental, closes communication and may increase isolation.

"Are you thinking about using those pills to end your life?": Correct. Stockpiling medication is a warning sign; asking directly about suicidal thoughts and plans does not increase risk and guides urgent safety steps.

"I'll tell your doctor to stop prescribing pain medicine.": Withdrawing analgesia is punitive, leaves pain untreated and does not assess or address risk.

Hoarded medication + hopelessness = ask directly about suicide, assess plan and means, stay safe, and escalate.