Data Analysis & Reporting Flashcards

Which of the following leg movement events should NOT be included in the PLM index calculation?

Answer: Movements occurring within 0.5 seconds of an apnea termination

AASM rules exclude leg movements occurring within 0.5 seconds before or after a respiratory event from the PLM count.

On a PSG report, WASO stands for:

Answer: Wake after sleep onset

WASO (Wake After Sleep Onset) is the total wake time occurring between sleep onset and the final awakening.

An EEG epoch shows a burst of 12–15 Hz activity lasting 0.5 seconds over central derivations. This should be scored as:

Answer: Sleep spindle

Sleep spindles are 12–15 Hz (sigma) bursts lasting ≥0.5 seconds, typically maximal over central derivations.

Which artifact most commonly mimics slow eye movements (SEMs) in EOG channels during drowsiness?

Answer: Sweat artifact

Sweat artifacts produce slow, broad deflections in EOG channels that can resemble slow eye movements and must be distinguished by context.

A patient has 45 minutes of REM sleep in 6.5 hours of TST. What is the REM sleep percentage?

Answer: 13.8%

REM % = (45 min ÷ 390 min) × 100 = 11.5%; however 45/390 = 0.1154, rounding to 11.5% — wait, 45/390=0.1154=11.5%. Select 11.5%.

In a PSG report, the respiratory disturbance index (RDI) differs from AHI because it also includes:

Answer: Respiratory effort-related arousals (RERAs)

RDI = AHI + RERA index; it counts apneas, hypopneas, AND respiratory effort-related arousals per hour of sleep.

A technologist reviewing a home sleep apnea test (HSAT) must remember that the AHI from HSAT is based on:

Answer: Total recording time rather than total sleep time

HSAT devices typically cannot confirm sleep; the AHI is therefore calculated per hour of total recording time, which can underestimate severity.