Research Methodology & Design Flashcards

Testing a pathogen PCR assay against closely related non-target organisms evaluates what?

Answer: Analytical specificity (exclusivity)

Exclusivity testing confirms the assay does not cross-react with related non-targets.

A study averages 3 wells per sample and treats all 30 wells from 10 subjects as n=30. What error has occurred?

Answer: Pseudoreplication

Treating non-independent technical replicates as independent inflates n and false significance.

What is the main advantage of digital PCR over qPCR for study design requiring absolute quantification?

Answer: It does not require a standard curve

Digital PCR uses Poisson statistics on partitions to quantify copies without a standard curve.

Which practice best reduces the risk of carryover contamination in laboratory workflow design?

Answer: Unidirectional workflow separating pre- and post-amplification areas

Physical separation and one-way flow prevent amplicons from reaching pre-PCR areas.

When testing many genes simultaneously for differential expression, what statistical adjustment is recommended?

Answer: Correction for multiple comparisons, such as false discovery rate control

Multiple testing inflates false positives, so FDR or similar corrections are applied.

A pilot study is most useful in PCR research design for which purpose?

Answer: Estimating variability to inform sample size and refining protocols

Pilot data provide variance estimates and reveal protocol problems before the main study.

Including an inter-run calibrator sample on every plate is intended to correct for what?

Answer: Run-to-run variation between plates

An inter-run calibrator allows Cq values from different plates to be compared by adjusting plate effects.