Should I Use a Wearable to Track My Sleep? A CBT-I Therapist’s Perspective

As a therapist who specializes in Cognitive Behavioral Therapy for Insomnia (CBT-I), I’m often asked the same question: “Should I use a wearable to track my sleep?” The rise of devices like the Fitbit, Apple Watch, Oura Ring, and others has made sleep data more accessible than ever. But how accurate are these tools, and should you rely on them to manage your sleep?

The Promise—and Limits—of Wearables

Most wearable companies report that their devices are highly accurate, and to a degree, that’s true. According to a 2024 article in the Journal of Sleep Medicine by J.E. Park and colleagues, the overall accuracy of Fitbit devices is estimated at 86.5%–88%. However, the breakdown reveals limitations:

• Light sleep: ~81% accuracy

• REM sleep: ~74% accuracy

• Deep sleep: only ~49% accuracy

This means that while wearables can give a general sense of your sleep architecture, they can be off by 20% to 50% in specific stages. That’s a wide margin if you’re hoping for precision.

Most wearables use heart rate variability and movement data to infer sleep states, but these signals can’t fully capture the nuances of your brain’s activity during sleep. So, while wearables may give you some clues, they’re not replacements for gold-standard methods like polysomnography or the subjective insights you gain from reflection and journaling.

What I Tell My Clients

I don’t discourage clients from using wearables—but I do recommend using them with realistic expectations. They can be helpful in a few key ways:

• Reducing “clock-watching” anxiety: Some people feel reassured having a general summary of their night instead of staring at the clock during awakenings. That can actually support better sleep.

• Getting a ballpark of sleep patterns: Wearables can help identify consistent trends, like late bedtimes or frequent awakenings.

• Validating perceptions: For some clients, seeing data that matches how they felt about their night can be empowering. For others, discrepancies between the data and how rested they feel can actually increase stress—so proceed with caution.

Ultimately, the usefulness of a wearable comes down to how you relate to the data. If you're becoming obsessive, anxious, or overly focused on numbers, it may be doing more harm than good. If you're taking the information with a grain of salt and using it as a curiosity rather than a judgment, it can offer some perspective.

The Subjective Side of Sleep

Wearables can only tell you so much. They cannot measure your subjective experience—how refreshed you feel, how well you function during the day, or how much your mood, stress, or environment impacted your sleep.

That’s why in CBT-I, we often recommend keeping a sleep journal. Document when you went to bed, when you fell asleep, how often you woke up, and how you felt in the morning. Equally important is noting what happened during the day—stressful events, caffeine intake, or exercise—which can all affect your night.

Final Thoughts

There’s nothing wrong with using a wearable as long as you understand its limits. It’s a tool, not a diagnosis. If you treat it as one small piece of the puzzle, alongside your own reflection and behavioral strategies, it can play a helpful role in improving sleep.

So the next time you wonder whether your wearable is telling the truth—ask yourself a different question: “Do I feel rested?” That answer, more than any algorithm, is what truly matters.

References: Park, J.E. (2024). Accuracy of Wearable Devices for Sleep Monitoring: A Review. Journal of Sleep Medicine, https://e-jsm.org/journal/view.php?doi=10.13078/jsm.240010

By Abby Neuberg LMFT