Skip to main content
Sign in Create a free account
Varsity Tutors
Sign in

Primary Literature Evaluation - NAPLEX

  1. A 45-year-old man (110 kg) with major depressive disorder has inadequate response after 8 weeks of sertraline 200 mg daily and reports sexual dysfunction. You review a randomized, double-blind trial in adults with selective serotonin reuptake inhibitor partial response: adjunctive bupropion sustained-release 150 mg twice daily vs adjunctive aripiprazole 5–15 mg daily for 12 weeks; remission occurred in 28% vs 32% (risk difference 4%; 95% confidence interval −2% to 10%; p=0.18), while treatment-emergent sexual dysfunction improved in 41% vs 18% (p<0.001) and weight gain ≥5% occurred in 3% vs 15% (p<0.001). Based on the study, which treatment is most appropriate for this patient?
    Answer: Add bupropion sustained-release because remission was similar, but bupropion improved sexual dysfunction and caused less clinically significant weight gain This question tests interpretation of adjunctive antidepressant therapy trials with multiple outcomes. The patient has SSRI partial response with sexual dysfunction, making tolerability outcomes crucial. The correct answer (B) recognizes that while remission rates were statistically similar (p=0.18 indicates no significant difference), bupropion showed superior tolerability with improved sexual function (41% vs 18%, p<0.001) and less weight gain (3% vs 15%, p<0.001). Option A misinterprets p=0.18 as showing superiority when it actually indicates no significant difference. Option C incorrectly dismisses evidence-based augmentation strategies. Option D misunderstands confidence intervals - including 0 for risk difference simply confirms no significant difference in remission. When efficacy is similar between treatments, prioritize patient-specific tolerability concerns and quality of life outcomes to guide selection.
  2. A 64-year-old woman (weight 68 kg) with osteoporosis is considering denosumab vs alendronate; she has difficulty adhering to weekly dosing. A pragmatic, open-label cohort study compared denosumab every 6 months vs alendronate weekly and found hip fracture rates of 1.2% vs 1.4% over 2 years (adjusted hazard ratio 0.92, 95% CI 0.70–1.20; p=0.52); adherence was higher with denosumab. Which study limitation is most relevant to consider in this case?
    Answer: Because it was an observational cohort study, residual confounding may explain the similar fracture rates and limits causal conclusions This question evaluates limitations of observational designs in comparative effectiveness research. The key study is a pragmatic, open-label cohort study comparing denosumab to alendronate, showing similar fracture rates but higher adherence with denosumab. The correct answer identifies residual confounding as a limitation due to the observational nature, relevant for this adherence-challenged patient. Choice B misinterprets p>0.05 as proving superiority; choice C wrongly claims open-label prevents objective outcomes; choice D confuses pragmatic with inapplicable. Common errors include treating cohorts as equivalent to RCTs. Pearl: Observational studies are useful for real-world data but require caution for causality. Framework: Assess study design hierarchy; prioritize RCTs for efficacy, cohorts for effectiveness and adherence insights.
  3. A 52-year-old man (weight 86 kg) with hypertension on amlodipine 10 mg daily has an average home blood pressure of 148/92 mmHg. A randomized controlled trial compared adding chlorthalidone 12.5–25 mg daily vs hydrochlorothiazide 25–50 mg daily for 12 weeks; mean systolic blood pressure reduction was -16.5 vs -12.0 mmHg (between-group difference -4.5 mmHg, 95% CI -6.8 to -2.2; p<0.001), with higher hypokalemia in the chlorthalidone group (6% vs 2%). Based on the study, which treatment is most appropriate for this patient?
    Answer: Add chlorthalidone because it lowered systolic blood pressure more than hydrochlorothiazide in a head-to-head randomized trial, with manageable monitoring for potassium This question assesses the clinical relevance of between-group differences in blood pressure reduction from a head-to-head randomized trial. The key study factor is the 12-week RCT comparing chlorthalidone to hydrochlorothiazide as add-on therapy, with greater SBP reduction but higher hypokalemia in chlorthalidone. The correct answer prefers chlorthalidone because its superior BP lowering is clinically meaningful for this uncontrolled patient, with potassium monitoring to manage risks. Choice A dismisses the difference as not meaningful despite statistical significance; choice C wrongly claims 12 weeks is too short for BP assessment; choice D misinterprets p<0.001 as indicating unsafety rather than significance. A common error is ignoring absolute differences in favor of p-values alone. Pearl: In hypertension management, consider both efficacy and tolerability when selecting agents from the same class. Framework: Evaluate head-to-head trials by balancing statistical significance with clinical importance and patient-specific risks.
  4. A 46-year-old woman (weight 80 kg) with major depressive disorder has had partial response to sertraline 100 mg daily. A randomized, double-blind trial compared augmenting with aripiprazole 2–15 mg daily vs placebo for 8 weeks; remission occurred in 25% vs 15% (number needed to treat 10), but akathisia occurred in 11% vs 2% (p<0.001). How should the study's findings influence this patient's treatment plan?
    Answer: Consider aripiprazole augmentation as an evidence-based option while counseling on and monitoring for akathisia This question tests balancing efficacy benefits with adverse event risks in augmentation trials for depression. The key study factor is the randomized, double-blind trial showing higher remission with aripiprazole augmentation but increased akathisia. The correct answer considers aripiprazole as evidence-based while monitoring for akathisia, applicable to this partial responder. Choice B misinterprets NNT>1 as no benefit; choice C wrongly prefers placebo due to equal remission misread; choice D dismisses RCTs for depression. A common misinterpretation is overlooking tolerability in favor of efficacy alone. Pearl: Augmentation strategies should weigh NNT against NNH in shared decision-making. Framework: Use metrics like NNT and NNH to quantify benefits and harms when applying psychiatric trial data.
  5. A 69-year-old man (weight 82 kg) with community-acquired pneumonia is being discharged after 2 inpatient days and is clinically improving. A randomized trial compared 5 total days of antibiotics vs 10 total days in clinically stable adults; clinical cure was 89% vs 88% (risk difference 1%, 95% CI -3% to 5%), and adverse drug events were 12% vs 20% (p=0.02). How should the study's findings influence this patient's treatment plan?
    Answer: Use a 5-day total course if he meets clinical stability criteria because cure rates were similar and adverse events were lower This question tests applying duration-of-therapy trials to de-escalation decisions. The key study is a randomized trial showing similar cure with fewer adverse events for 5 versus 10 days in stable pneumonia patients. The correct answer supports a 5-day course for this improving patient, reducing adverse events. Choice B misinterprets CI; choice C assumes longer is better without evidence; choice D errs on randomization limiting applicability. Common misinterpretations include fearing shorter durations without data. Pearl: Shorter antibiotic courses minimize resistance and harm when efficacy is equivalent. Framework: Evaluate duration trials by clinical stability criteria for safe de-escalation.
  6. A 63-year-old man (85 kg) with heart failure with reduced ejection fraction (left ventricular ejection fraction 30%) is stable on carvedilol, sacubitril/valsartan, and spironolactone; he has type 2 diabetes and eGFR 58 mL/min/1.73 m2^2. You review a randomized, double-blind trial of dapagliflozin 10 mg daily vs placebo added to guideline-directed therapy in heart failure with reduced ejection fraction; the primary composite of worsening heart failure or cardiovascular death occurred in 16.3% vs 21.2% (hazard ratio 0.74; 95% confidence interval 0.65–0.85; p<0.001), with similar benefit in patients with and without diabetes. Based on the study, which treatment is most appropriate for this patient?
    Answer: Add dapagliflozin 10 mg daily because the trial showed reduced worsening heart failure or cardiovascular death on top of standard therapy, including in patients with diabetes and eGFR similar to his This question tests application of SGLT2 inhibitor trials in heart failure with comorbidities. The patient has HFrEF on guideline-directed therapy with diabetes and CKD stage 3a, matching the trial population. The correct answer (B) appropriately applies the trial's significant benefit (HR 0.74, p<0.001) for the composite outcome, noting the benefit was consistent in diabetes subgroups and the eGFR is adequate for dapagliflozin use. Option A incorrectly claims benefit was limited to non-diabetics when the trial showed similar benefit regardless of diabetes status. Option C misunderstands the trial design - dapagliflozin was added to, not compared against, standard therapy including MRAs. Option D misinterprets hazard ratios - values below 1.0 indicate reduced, not increased risk. When applying heart failure trials, ensure patients are on optimal background therapy and recognize that SGLT2 inhibitors provide additive benefit regardless of diabetes status.
  7. A 52-year-old woman (64 kg) with moderate persistent asthma uses budesonide-formoterol 160/4.5 mcg 2 inhalations twice daily but still has 2 exacerbations requiring oral prednisone in the last year. You review a randomized, double-blind, active-controlled trial comparing add-on tiotropium Respimat 2.5 mcg (2 inhalations once daily) vs doubling the inhaled corticosteroid dose for 48 weeks; severe exacerbation rate was 0.28 vs 0.34 per patient-year (rate ratio 0.82; 95% confidence interval 0.70–0.96; p=0.01) and mean forced expiratory volume in 1 second improved by 90 mL vs 40 mL (p=0.03). Which study limitation is most relevant to consider in this case?
    Answer: The active comparator was inhaled corticosteroid dose escalation, but adherence and inhaler technique were not objectively verified, which could bias exacerbation outcomes This question tests critical appraisal of study limitations in asthma trials. The patient has moderate persistent asthma with exacerbations despite combination therapy. The correct answer (B) identifies a key limitation: while the trial was randomized and double-blind, adherence and inhaler technique verification could significantly impact exacerbation outcomes when comparing add-on therapy versus ICS escalation. Option A incorrectly dismisses external validity concerns in well-designed trials. Option C misinterprets statistical significance - p=0.01 confirms the difference is real, not clinically meaningless. Option D incorrectly identifies the study design as cohort when it's clearly described as randomized. When evaluating asthma trials, consider that poor adherence and technique are common reasons for apparent treatment failure, and trials without objective verification may not reflect real-world effectiveness differences.
  8. A 35-year-old man (weight 90 kg) with chronic plaque psoriasis is considering starting adalimumab. A randomized, double-blind trial compared adalimumab vs placebo for 16 weeks; 75% improvement in Psoriasis Area and Severity Index occurred in 71% vs 7% (p<0.001), but the trial excluded patients with active infection and those with untreated latent tuberculosis. What is the key takeaway from the study for this patient's case?
    Answer: Adalimumab is highly effective for plaque psoriasis, but screening for infection risk (including tuberculosis) is essential because excluded populations limit applicability This question assesses the impact of exclusion criteria on safety considerations in biologic trials. The key study factor is the randomized, double-blind trial of adalimumab versus placebo in psoriasis, excluding active infections and untreated latent TB. The correct answer highlights adalimumab's efficacy but stresses infection screening due to exclusions limiting applicability. Choice B misreads response rates; choice C errs on p-value meaning; choice D wrongly states TB inclusion. A common misinterpretation is ignoring exclusions in risk assessment. Pearl: For immunosuppressants, always screen for infections per guidelines before initiation. Framework: Evaluate trial exclusions to identify gaps in safety data for high-risk patients.
  9. A 27-year-old man (weight 76 kg) with generalized anxiety disorder is choosing between escitalopram and venlafaxine extended-release. A randomized, double-blind head-to-head trial for 12 weeks found response rates of 62% with escitalopram vs 64% with venlafaxine (p=0.64), but discontinuation due to adverse events was 6% vs 13% (p=0.01). Based on the study, which treatment is most appropriate for this patient?
    Answer: Escitalopram because efficacy was similar but tolerability favored escitalopram with fewer discontinuations This question assesses balancing efficacy and tolerability in head-to-head psychiatric trials. The key study factor is the randomized, double-blind trial showing similar response but better tolerability with escitalopram versus venlafaxine XR. The correct answer prefers escitalopram due to comparable efficacy with fewer discontinuations, suitable for this GAD patient. Choice A misreads significance for response; choice C dismisses difference despite p=0.01; choice D wrongly dismisses head-to-head RCTs. A common error is prioritizing small efficacy edges over tolerability. Pearl: In anxiety disorders, tolerability often drives long-term adherence. Framework: Use discontinuation rates as a proxy for real-world tolerability in comparative trials.
  10. A 55-year-old man (weight 83 kg) with chronic low back pain is considering duloxetine. A randomized, double-blind trial compared duloxetine 60 mg daily vs placebo for 12 weeks; average pain score decreased by 1.2 vs 0.7 on a 0–10 scale (difference -0.5; p=0.004), but nausea occurred in 18% vs 6% and discontinuation due to adverse events was 9% vs 4%. How should the study's findings influence this patient's treatment plan?
    Answer: Duloxetine may offer modest pain reduction versus placebo; consider patient goals and tolerability, and monitor for adverse effects This question evaluates balancing modest pain relief with adverse effects in chronic pain trials. The key study is a randomized, double-blind trial showing small pain score improvement with duloxetine versus placebo, but higher nausea and discontinuations. The correct answer suggests duloxetine as an option with monitoring and goal discussions for this patient. Choice B overstates p=0.004 significance; choice C misreads negative difference as worse; choice D dismisses placebo-controlled trials. Common misinterpretations include expecting dramatic improvements in chronic conditions. Pearl: Multimodal approaches often needed for chronic pain management. Framework: Use effect sizes and tolerability data to inform shared decisions in pain literature.
  11. A 31-year-old woman (weight 58 kg) who is 10 weeks pregnant has nausea and vomiting not controlled with lifestyle changes. A randomized, double-blind trial in pregnant patients compared doxylamine/pyridoxine vs placebo for 14 days; symptom score improved by 4.8 vs 3.9 points (difference 0.9; p=0.02), with somnolence 14% vs 9%. What is the clinical significance of the study's findings for this patient?
    Answer: Doxylamine/pyridoxine provides a small but statistically significant symptom improvement and is a reasonable option with counseling about somnolence This question tests minimal clinically important differences in symptom-based trials. The key study factor is the randomized, double-blind trial showing small symptom improvement with doxylamine/pyridoxine versus placebo in pregnancy, with mild somnolence increase. The correct answer notes its modest benefit as reasonable with somnolence counseling for this patient. Choice B overstates somnolence as unacceptable; choice C dismisses small difference as no benefit; choice D wrongly questions RCT ethics in pregnancy. A common error is requiring large effects for significance. Pearl: In nausea of pregnancy, start with non-pharmacologic then evidence-based options. Framework: Define MCID thresholds to assess clinical relevance beyond p-values.
  12. A 74-year-old man (weight 78 kg) with heart failure with reduced ejection fraction (left ventricular ejection fraction 30%) is stable on carvedilol, lisinopril, and spironolactone; blood pressure is 118/70 mmHg and estimated glomerular filtration rate is 48 mL/min/1.73 m2^2. A randomized, double-blind trial evaluated adding dapagliflozin 10 mg daily vs placebo in patients with heart failure with reduced ejection fraction (with or without diabetes) for a median 18 months; the primary composite (cardiovascular death or worsening heart failure) occurred in 16.3% vs 21.2% (hazard ratio 0.74, 95% CI 0.65–0.85; p<0.001). What is the clinical significance of the study's findings for this patient?
    Answer: Dapagliflozin reduced cardiovascular death/worsening heart failure and is clinically meaningful to add to guideline-directed therapy in an eligible patient like this This question tests the application of composite outcomes and hazard ratios in heart failure trials to patient care. The key study is a randomized, double-blind trial of dapagliflozin versus placebo in HFrEF patients, including those without diabetes and with eGFR as low as 30 mL/min/1.73 m². The correct answer highlights dapagliflozin's reduction in CV death/worsening HF as clinically meaningful for this eligible patient on guideline therapy. Choice B is incorrect as the trial included non-diabetics; choice C misinterprets HR<1.0 as harm; choice D errs as the trial allowed eGFR ≥30, matching this patient's 48. Common misinterpretations involve misunderstanding inclusion criteria. Pearl: SGLT2 inhibitors offer cardiorenal benefits beyond glycemic control in HFrEF. Framework: When applying trial results, confirm patient matches key eligibility criteria like eGFR and comorbidities.
  13. A 58-year-old man (weight 92 kg) with type 2 diabetes (A1c 8.6%) and chronic kidney disease stage 3a (estimated glomerular filtration rate 52 mL/min/1.73 m2^2) asks about adding oral semaglutide versus sitagliptin to metformin. A randomized, double-blind trial in adults with type 2 diabetes on metformin (mean baseline A1c 8.3%; excluded estimated glomerular filtration rate <30) compared oral semaglutide 14 mg daily vs sitagliptin 100 mg daily for 26 weeks; mean A1c change was -1.3% vs -0.8% (between-group difference -0.5%, 95% CI -0.6 to -0.3; p<0.001) and weight change was -3.8 kg vs -0.7 kg (p<0.001), with more gastrointestinal adverse events on semaglutide (nausea 20% vs 7%). How should the study's findings influence this patient's treatment plan?
    Answer: Prefer oral semaglutide because it produced greater A1c and weight reduction than sitagliptin in a similar population and his kidney function meets the trial's inclusion criteria This question tests the concept of external validity and applicability of trial results to individual patients based on inclusion/exclusion criteria. The key study factor is the randomized, double-blind trial comparing oral semaglutide to sitagliptin in patients with type 2 diabetes on metformin, with exclusion of those with eGFR <30 mL/min/1.73 m². The correct answer prefers oral semaglutide because it showed superior A1c and weight reduction in a population similar to this patient, whose eGFR of 52 meets the trial's criteria, allowing reasonable extrapolation. Choice A is incorrect because the trial did not exclude eGFR <60, only <30, so results can apply; choice C misinterprets the p<0.001 as indicating no significance; choice D is wrong as 26 weeks is adequate for assessing glycemic effects. A common misinterpretation is overemphasizing exclusion criteria without checking patient alignment. When evaluating literature, assess if patient characteristics match trial demographics to determine applicability. Always balance efficacy benefits with adverse event profiles, like gastrointestinal effects here, in shared decision-making.
  14. A 62-year-old man (weight 90 kg) with type 2 diabetes (A1c 7.9%) and established atherosclerotic cardiovascular disease is considering empagliflozin. A cardiovascular outcomes randomized trial compared empagliflozin vs placebo added to standard care; cardiovascular death occurred in 3.7% vs 5.9% (hazard ratio 0.62, 95% CI 0.49–0.77; p<0.001), while nonfatal myocardial infarction was not significantly different (p=0.22). What is the key takeaway from the study for this patient's case?
    Answer: Empagliflozin reduced cardiovascular death in patients with type 2 diabetes and established cardiovascular disease, supporting its use for cardiovascular risk reduction This question assesses hierarchical outcomes in cardiovascular safety trials. The key study is a randomized CV outcomes trial showing reduced CV death with empagliflozin in T2D with ASCVD, despite neutral nonfatal MI. The correct answer supports empagliflozin for CV risk reduction in this matching patient. Choice B dismisses due to one neutral component; choice C misinterprets HR<1.0; choice D errs on population applicability. Common misinterpretations involve overemphasizing secondary endpoints. Pearl: SGLT2is provide CV benefits in high-risk T2D beyond glucose control. Framework: Focus on primary outcomes but review components for comprehensive application.
  15. A 50-year-old man (90 kg) with chronic pain is starting clopidogrel after a transient ischemic attack and asks whether genetic testing matters. You review a randomized trial in patients undergoing antiplatelet therapy where CYP2C19 loss-of-function carriers were assigned to genotype-guided therapy (ticagrelor 90 mg twice daily for carriers; clopidogrel 75 mg daily for noncarriers) vs standard therapy (clopidogrel 75 mg daily for all) for 12 months; among carriers, ischemic events occurred in 4.0% genotype-guided vs 6.5% standard (risk ratio 0.62; 95% confidence interval 0.40–0.96; p=0.03) with no significant increase in major bleeding (1.6% vs 1.4%; p=0.70). How should the study's findings influence this patient's treatment plan?
    Answer: Order CYP2C19 testing; if he is a loss-of-function carrier, consider switching to ticagrelor because genotype-guided therapy reduced ischemic events without increasing major bleeding in carriers This question tests interpretation of pharmacogenomic-guided therapy trials. The patient is starting clopidogrel for secondary prevention where CYP2C19 status affects drug metabolism. The correct answer (A) appropriately applies the trial showing genotype-guided therapy reduced ischemic events in carriers (RR 0.62, p=0.03) without increasing bleeding, supporting testing to identify carriers who benefit from alternative therapy. Option B dismisses a statistically significant finding based on p-value misinterpretation. Option C overgeneralizes by suggesting all patients need ticagrelor when benefit was specific to carriers. Option D incorrectly describes the study design - it was randomized, not observational. Pharmacogenomic trials demonstrate that targeted therapy based on genetic markers can improve outcomes in specific subgroups; when evidence supports differential treatment response, testing enables personalized therapy selection.
  16. A 39-year-old woman (60 kg) with migraine has 5–6 migraine days per month despite propranolol; she is considering an oral calcitonin gene-related peptide (CGRP) antagonist for prevention. You review a randomized, double-blind, placebo-controlled trial of atogepant 30 mg daily vs placebo for 12 weeks in episodic migraine (baseline 7.5 monthly migraine days); reduction in monthly migraine days was −3.7 vs −2.5 (least-squares mean difference −1.2 days; 95% confidence interval −1.6 to −0.8; p<0.001), with nausea in 9% vs 4%. What is the clinical significance of the study's findings for this patient?
    Answer: Atogepant provides an average additional reduction of about 1 migraine day per month versus placebo, which may be meaningful if she values fewer monthly migraine days and tolerates nausea risk This question evaluates interpretation of migraine prevention trial results and clinical significance. The patient has 5-6 monthly migraine days, similar to the trial population's baseline of 7.5 days. The correct answer (A) appropriately interprets the statistically significant but modest absolute benefit (1.2 fewer days per month) and acknowledges this may be meaningful depending on patient values, while noting the increased nausea risk (9% vs 4%). Option B misunderstands confidence intervals - excluding 0 confirms statistical significance. Option C overstates efficacy by confusing within-group change with between-group difference. Option D incorrectly limits applicability based on baseline frequency when the trial studied episodic migraine. When interpreting prevention trials, focus on absolute risk reduction and number needed to treat while considering patient-specific values about meaningful improvement versus adverse effects.
  17. A 57-year-old woman (weight 69 kg) with chronic hepatitis C is being evaluated for treatment, but her genotype result is pending. A randomized trial of a pan-genotypic regimen reported sustained virologic response at 12 weeks of 95% vs 46% with placebo (p<0.001), but the study excluded patients with decompensated cirrhosis (Child-Pugh class B or C). Which study limitation is most relevant to consider in this case?
    Answer: Exclusion of decompensated cirrhosis limits applicability to patients with advanced liver disease, so liver function status must be considered before applying results This question assesses the impact of exclusion criteria on generalizability in infectious disease trials. The key study factor is the randomized trial of a pan-genotypic HCV regimen excluding decompensated cirrhosis, showing high SVR versus placebo. The correct answer identifies exclusion of advanced liver disease as limiting applicability, relevant if this patient's status is severe. Choice B misstates placebo use affecting randomization; choice C overgeneralizes safety; choice D errs on p-value implication. Common misinterpretations include ignoring exclusions for safety. Pearl: Assess liver function staging before HCV treatment selection. Framework: Review trial exclusions to ensure patient safety when extrapolating efficacy data.
  18. A 45-year-old man (weight 91 kg) with hypertension is starting clopidogrel after percutaneous coronary intervention; pharmacogenomic testing shows CYP2C19 poor metabolizer status. A randomized trial in patients undergoing percutaneous coronary intervention compared genotype-guided therapy (ticagrelor for poor/intermediate metabolizers; clopidogrel for normal metabolizers) vs standard clopidogrel; the composite of cardiovascular death, myocardial infarction, stroke, or stent thrombosis occurred in 5.1% vs 6.9% (hazard ratio 0.74, 95% CI 0.60–0.92; p=0.006), with similar major bleeding (2.3% vs 2.1%; p=0.70). Based on the study, which treatment is most appropriate for this patient?
    Answer: Switch to ticagrelor because genotype-guided selection reduced ischemic outcomes without increasing major bleeding, and he is a CYP2C19 poor metabolizer This question tests the application of pharmacogenomic-guided therapy in primary literature evaluation for antiplatelet selection post-percutaneous coronary intervention. The key study is a randomized controlled trial comparing genotype-guided antiplatelet therapy (ticagrelor for CYP2C19 poor or intermediate metabolizers and clopidogrel for normal metabolizers) versus standard clopidogrel therapy in patients undergoing percutaneous coronary intervention. The correct choice, switching to ticagrelor, best reflects the study's findings because the patient is a CYP2C19 poor metabolizer, and genotype-guided therapy significantly reduced ischemic outcomes (HR 0.74, p=0.006) without increasing major bleeding compared to standard clopidogrel. Choice A is incorrect because genotype-guided therapy actually decreased ischemic events, not increased them, representing a misinterpretation of the hazard ratio and p-value. Choices C and D are suboptimal; C ignores the need for antiplatelet therapy post-intervention and misfocuses on unchanged bleeding rates, while D incorrectly defines statistical significance as p greater than 0.05 rather than less than 0.05. A key clinical pearl is to prioritize genotype-guided strategies in CYP2C19 poor metabolizers to optimize ischemic risk reduction while monitoring for bleeding equivalence. When evaluating primary literature, always assess how patient-specific factors like pharmacogenomics align with study inclusion criteria and outcomes to guide individualized therapy.
  19. A 29-year-old woman (55 kg) is 10 weeks postpartum and breastfeeding; she has a history of major depressive disorder and requests medication. You review a prospective cohort study comparing infants exposed via breast milk to sertraline vs paroxetine vs no selective serotonin reuptake inhibitor exposure (follow-up 6 months); the primary outcome was infant weight gain percentile change, which was similar across groups (mean difference sertraline vs no exposure +0.4 percentile points; 95% confidence interval −1.8 to 2.6), and reported infant sedation occurred in 1.2% sertraline vs 1.0% no exposure. What is the key takeaway from the study for this patient's case?
    Answer: Sertraline appears compatible with breastfeeding because infant growth outcomes were similar to no exposure and sedation was uncommon in this cohort This question evaluates interpretation of observational safety data in breastfeeding. The patient needs antidepressant therapy while breastfeeding, where randomized trials are unethical. The correct answer (A) appropriately interprets the cohort study showing similar infant growth outcomes (confidence interval includes 0) and low sedation rates (1.2% vs 1.0%) as reassuring safety data. Option B overinterprets rare adverse events as contraindications without considering baseline rates. Option C incorrectly infers efficacy comparisons from a safety-focused cohort study. Option D misunderstands the study design - it was observational, not randomized, which is appropriate for breastfeeding safety questions. When evaluating medication safety in pregnancy/lactation, prospective cohort studies provide the best available evidence; similar outcomes to unexposed infants with low absolute adverse event rates support compatible use with appropriate monitoring.
  20. A 61-year-old man (weight 95 kg) with hyperlipidemia and prior myocardial infarction is on atorvastatin 80 mg daily; low-density lipoprotein cholesterol remains 92 mg/dL. A randomized, double-blind trial in patients with atherosclerotic cardiovascular disease on maximally tolerated statin compared adding ezetimibe 10 mg daily vs placebo for 6 years; the primary composite cardiovascular outcome occurred in 32.7% vs 34.7% (hazard ratio 0.94, 95% CI 0.89–0.99; p=0.016), with an absolute risk reduction of 2.0%. What is the clinical significance of the study's findings for this patient?
    Answer: Adding ezetimibe provides a modest but statistically significant reduction in cardiovascular events and is reasonable to add for secondary prevention This question assesses the clinical significance of modest hazard ratio reductions in cardiovascular outcomes trials. The key study is a randomized, double-blind trial of ezetimibe added to statins in ASCVD patients, showing a small but significant reduction in composite CV events. The correct answer supports adding ezetimibe for its evidence-based benefit in secondary prevention for this patient with elevated LDL on maximal statin. Choice B misinterprets HR 0.94>0 as no benefit despite CI excluding 1.0; choice C wrongly limits to primary prevention; choice D errs in calling it observational. Common errors include dismissing small absolute reductions as irrelevant. Pearl: Incremental LDL lowering with adjuncts like ezetimibe can provide additive CV risk reduction. Framework: Evaluate add-on therapies by absolute risk reduction and number needed to treat for patient discussions.

Start this quiz