NEW! ARC specialty clinic in Round Rock

Effective Monday, January 19, 2026, ARC opens a new specialty clinic, ARC Greenlawn Specialty, with 15 physicians and advanced practice clinicians (APCs) relocating practices to this clinic. If this change affects your appointment(s), you will receive communications via email, text, or phone. Please be sure to read all notifications from ARC. Read more.

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Christopher Darnall

Christopher K. Darnall, MD Pronunciation Guide

Neurology
Sleep Neurology

ARC Patient Feedback

Guide to ARC Patient Feedback and Ratings

Austin Regional Clinic (ARC) doctors, staff, and leadership are committed to providing our community with high quality convenient care. One of the ways we demonstrate this priority is through our online transparency.

You can review our provider ratings and comments on our web site with the confidence that they are all based on verified visits. We post all patient feedback relevant to the entire visit and only refrain from posting comments that are libelous, profane, or those that risk the privacy of our patients.

The below guide provides details about how we collect and share our patient feedback.

Who runs the survey?

ARC partnered with Press Ganey to collect patient feedback about their doctor’s visit. We gather feedback from text surveys that are sent after the visit. Press Ganey is an independent third party customer feedback company that provides the technology to collect the feedback and display ratings and comments on our web site. All ratings are submitted by actual patients and verified by ARC.

How do patients receive the survey?

Patients for whom we have a mobile phone number receive a text survey within two hours of checking in for their visit. Patients are asked to complete the survey and provide ratings and comments regarding their experience at different touch points of their visit. We use this feedback to recognize doctors and staff, identify issues we can correct, and enhance our care.

Do you post all positive and negative comments?

ARC posts all positive and negative patient feedback that is relevant to the entire visit. We refrain from posting comments that are libelous, profane, or those that risk the privacy of our patients.

What questions do we ask?

ARC asks questions that touch on the overall patient experience related to their visit. Anyone seeking detailed information about each question can view the ratings for each specific question on the Reviews tab on the provider bio page on the website. We calculate our provider star ratings based on the responses to question number six below. We calculate our location star ratings based on the responses to all the below questions.

  1. Rate how easy it was to make your appointment.
  2. Rate the helpfulness of the front-desk staff.
  3. Rate the helpfulness of the doctor's nurse and/or medical assistant (MA).
  4. Did the healthcare provider or doctor provide the care you expected?
  5. How likely is it that you would refer a friend/family member to this doctor or NP/PA?
  6. Please let us know anything that you particularly liked or disliked about your experience with today’s office visit.

Why don't all providers display a rating?

Since more recent data provides a more accurate picture, we require a minimum of 30 patient surveys per doctor in the last 12 months before we post a physician’s rating.

Why can I only see comments from the last 90 days?

ARC physicians and staff review all comments and act to rectify issues. Since the purpose of the feedback is to allow us to improve the overall patient experience, we display the last 90 days of comments which are the most relevant for the practice.

Can anyone complete a survey or post a comment about a physician?

No. Only patients having an outpatient visit by an ARC physician receive a survey. The results are based entirely from patients who have actually been treated by the physician in our clinics.

How is patient information protected?

Comments are reviewed and approved prior to being published to the website. If a comment contains any personally identifiable information, that information will be removed from the comment.

Accepting new patients ARC Four Points Ages seen: 18 - 99 Joined ARC: 2026

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About Christopher K. Darnall, MD

  • Dr. Darnall grew up in Jackson, MS. In his free time, he enjoys spending time with his wife and two daughters and their two dogs. Dr. Darnall likes to exercise by swimming and trail running, and he enjoys cooking and traveling with friends. His favorite Central Texas spot is Barton Springs pool.

In school, my favorite courses were in the biological sciences. I loved learning about the natural world and scientific discoveries, but I was not drawn to research. Medicine offered a practical application for science that would let me care for patients and continue to learn. I became fascinated with the brain and neurophysiology. Sleep medicine emerged as a new frontier in neuroscience that has direct and indirect effects on quality of life, performance, and overall health. My approach is to be kind, to listen, to advise, and to collaborate with my patients in selection of tools that provide the best means of symptomatic improvement.

Services

Diagnostic Sleep Testing and Interpretation

Diagnostic Sleep Testing and Interpretation

ARC sleep neurologists order and interpret diagnostic sleep studies, including polysomnography, multiple sleep latency tests, and home sleep tests.

Evaluation and Treatment of Sleep Disorders

Evaluation and Treatment of Sleep Disorders

ARC sleep neurologists provide care for a variety of sleep disorders, including obstructive and central sleep apnea, narcolepsy, idiopathic hypersomnia, parasomnia, REM sleep behavior disorder, sleep terrors, sleepwalking, restless legs syndrome, periodic limb movement disorder, circadian rhythm disorders, and insomnia.

Locations & Hours

Credentials

  • Board Certifications
    Board Certified in Sleep Medicine
  • Fellowship
    Clinical Neurophysiology (2007) and Sleep Medicine (2008), University of Texas Health Science Center Houston, TX
  • Residency
    Internal Medicine Internship, University of Texas Health Science Center Houston, TX, 2003

    Neurology Residency, University of Texas Health Science Center Houston, TX, 2006
  • Medical School
    University of Mississippi School of Medicine, Jackson, MS, 2002
  • Education
    BA in Biology, The University of Texas at Austin, 1998
  • Professional Positions
    • Member, Travis County Medical Society
    • Member, American Academy of Sleep Medicine
    • Member, Texas Neurological Society

Mentions

Surgical providers

Surgical providers are specially trained and licensed physicians who can perform surgical procedures to treat injuries, diseases, and other health conditions. Surgical providers can also diagnose and manage medical conditions, oversee pre-operative and post-operative care, and work closely with your primary care team to coordinate your care.

Non-surgical providers

Non-surgical providers are highly trained and licensed physicians, physician assistants, and nurse practitioners who specialize in diagnosing, managing, and treating medical conditions through non-surgical medical care.

Ages Seen

Children (ages 3-11)
Adolescents (ages 12-18)
Toddlers (ages 0-2)