The technical success rate of home sleep testing (HST) devices has steadily improved decade by decade. Some HSTs today allow for duplicate sensors in case one falls off during the study, and several use accelerometry-based algorithms that estimate actual sleep time despite not incorporating an EEG. However, user error remains a challenge that prevents HSTs from being as accurate as in-lab sleep studies. Sleep professionals must ensure that when faced with a technically inadequate study, the patient is re-studied—either with a second HST or with an in-lab PSG.

According to a recent Sleep Review webinar “Get Reliable HST Results the First Time,” the number-one reason for unusable HST studies is patient error in setting up the device at home (identified by 42.3% of attendees as the most common reason). Many attendees (38.4%) cited patient error post-device-set-up, such as a sensor falling off, as their biggest obstacle. Much less common, according to the webinar poll, are not enough time in bed/time asleep (13.5%) and equipment error or failure (5.8%).

Patient error may include placing a belt in the wrong position or forgetting to push the device’s “on” button. Some of these errors may be mitigated by built-in alarms or alerts on the device itself; some HSTs will notify the patient if, for example, the cannula has fallen out. So be cognizant of what alerts would be most useful to your patient population when making future device purchases.

What options do sleep centers utilize when patient error renders an HST study unreadable? Webinar presenter Andrea Ramberg, RPSGT, says her employer Centegra Health System will give the patient the benefit of the doubt and will typically do the home study again. “Most of the time, we won’t charge for that first one [if the results are unusable], or we’ll charge a minor fee,” Ramberg shared during the Q&A. Some insurance companies will cover a second HST if the first one returns inadequate results, but Ramberg’s experience with not charging is certainly a lower-hassle solution. Another option sometimes employed at Centegra Health is bringing the patient in for an in-lab study, thereby virtually eliminating any chance of patient error.

In a study published in the Journal of Clinical Sleep Medicine of 111 patients who had a technically inadequate HST, 71% were diagnosed with obstructive sleep apnea in a subsequent PSG.1 “There’s definitely a reason to re-test in an attended setting when you have a technically inadequate study,” said Alyssa Cairns, PhD, citing this study in the webinar. She also noted that at least 5 hours of recording is needed to ensure that the study is representative of the patient’s sleep breathing.2

Of course, 20 minutes of prevention can be worth 300 minutes of re-testing. All 3 webinar presenters—Ramberg, Cairns, and Keith Knittle, RPSGT—noted that patient education at the time of device delivery is paramount to a reliable home sleep study. Thorough education can give both you and the patient the confidence that the study will be done seamlessly the first time.

1. Zeidler MR, Santiago V, Dzierzewski JM, Mitchell MN, Santiago S, Martin JL. Predictors of obstructive sleep apnea on polysomnography after a technically inadequate or normal home sleep test. J Clin Sleep Med 2015;11(11):1313–1318.
2. Wittine LM, Olson EJ, Morgenthaler TI. Effect of Recording Duration on the Diagnostic Accuracy of Out-of-Center Sleep Testing for Obstructive Sleep Apnea. Sleep. 2014 May 1;37(5):969–975.