RPSGT Data Analysis & Reporting 3 — Questions and Answers
Question 1: In the final PSG report, Total Sleep Time (TST) is calculated as:
- Time in bed minus time awake after sleep onset
- Lights out to lights on
- Sleep onset to final awakening
- Total recording time minus all wake periods (Correct answer)
Correct answer: Total recording time minus all wake periods
TST equals total recording time minus all wake epochs (including pre-sleep wake, WASO, and wake after final awakening).
Question 2: Which scoring rule applies when a mixed apnea transitions from a central to an obstructive pattern?
- Score as central apnea
- Score as obstructive apnea
- Score as mixed apnea (Correct answer)
- Score as hypopnea
Correct answer: Score as mixed apnea
Events beginning with absent respiratory effort and ending with obstructive features are scored as mixed apneas.
Question 3: A technologist notes chin EMG bursts lasting 0.1–0.5 seconds occurring in REM sleep. These are best described as:
- REM sleep behavior disorder activity
- Phasic REM muscle activity (Correct answer)
- Sleep bruxism
- Hypnic jerks
Correct answer: Phasic REM muscle activity
Short, irregular chin EMG bursts (0.1–0.5 sec) during REM are classified as phasic REM muscle activity per AASM scoring rules.
Question 4: Sleep efficiency is best defined as:
- REM time divided by total recording time
- TST divided by total recording time × 100
- TST divided by time in bed × 100 (Correct answer)
- NREM time divided by TST × 100
Correct answer: TST divided by time in bed × 100
Sleep efficiency = (TST ÷ time in bed) × 100, where time in bed runs from lights out to lights on.
Question 5: During REM sleep, which finding would prompt a technologist to flag for possible REM sleep behavior disorder?
- Absence of sleep spindles
- Sustained chin EMG elevation throughout REM epochs (Correct answer)
- Alpha rhythm intrusion
- Increased delta power
Correct answer: Sustained chin EMG elevation throughout REM epochs
RBD is characterized by loss of normal REM atonia — sustained or repeated chin EMG elevation during REM epochs is the key PSG marker.
Question 6: What is the inter-scorer reliability statistic most commonly used to evaluate PSG staging agreement?
- Pearson correlation coefficient
- Cohen's kappa (Correct answer)
- Spearman rho
- Intraclass correlation coefficient
Correct answer: Cohen's kappa
Cohen's kappa is the standard statistic for measuring inter-rater agreement on categorical sleep stage scores.
Question 7: A CSR (Cheyne-Stokes respiration) pattern requires a minimum of how many central apneas or hypopneas?
- 2
- 3 (Correct answer)
- 4
- 5
Correct answer: 3
AASM criteria for CSR require ≥3 consecutive central apneas/hypopneas with a cyclic crescendo-decrescendo pattern.
RPSGT Data Analysis & Reporting 3
In the final PSG report, Total Sleep Time (TST) is calculated as: