Clinicomm set 2

In a hospital outbreak investigation of carbapenem-resistant Klebsiella pneumoniae, which study design best determines the risk factors for colonization among ICU patients while controlling for confounders?

• Cross-sectional

• Case-control with matching

• Prospective cohort

• Ecological

During an RCT assessing a new rapid sepsis screening tool, interim analysis shows borderline benefit (p=0.049). Which approach avoids inflated Type I error?

• Original p-value

• Bonferroni

• Sequential boundaries (O'Brien-Fleming)

• Stop now

Non-inferiority trial of two HAP regimens: CI for difference in cure rates lies entirely within the non-inferiority margin. Interpretation?

• Inferior

• Non-inferior

• Superior

• Inconclusive

Early discharge protocol using troponin: NPV is 99% in low-risk chest pain. What most affects NPV?

• Sensitivity

• Specificity

• Disease prevalence

• Sample size

Hospital hand hygiene observations: Hawthorne effect will most likely…

• Inflate observed compliance

• Deflate

• No effect

• Increase random error

Oncology survival analysis violates proportional hazards. Best alternative?

• Log-rank only

• Cox with time-varying covariates/stratified Cox

• Paired t-test

• Ignore

ICU sepsis bundle trial: RR=0.85 (95% CI: 0.60-1.02).

• Statistically significant

• Clinically meaningful but not statistically significant

• No relevance

• Both

Retrospective decade-long liver transplant outcomes at a tertiary center: most likely bias?

• Recall

• Lead-time

• Selection bias

• Measurement

Time-series of monthly CAUTI rates before/after silver catheters. Best method for autocorrelation?

• Chi-square

• ARIMA

• ANOVA

• Logistic regression

Hip-rehab trial with large loss to follow-up in one arm. Most robust analysis?

• Per-protocol

• Intention-to-treat

• On-treatment

• Sensitivity only