FAQs for HOPDs and ASCs

What is OAS CAHPS?

The Consumer Assessment of Healthcare Providers and Systems Outpatient and Ambulatory Surgery (OAS CAHPS) survey is a patient experience of care survey for Medicare-certified hospital outpatient departments (HOPDs) and ambulatory surgery centers (ASCs).

How was the survey developed?

The survey development process followed the principles and guidelines outlined by the Agency for Healthcare Research and Quality (AHRQ) and its Consumer Assessment of Health Providers and Systems (CAHPS® ) Consortium in developing a patient experience of care survey. This included reviewing surveys submitted as a result of a public call for measures; reviewing existing literature; conducting focus groups with patients who had recent outpatient surgery or procedures; conducting cognitive interviews with patients to test their understanding and ability to answer the questions; obtaining stakeholder input on the draft survey and other issues that may impact survey implementation; and conducting a field test in 2014. The goal of the survey development process was to identify and include dimensions of care that patients and other consumers want or need to inform their choice of an HOPD or ASC. In 2015, CMS conducted a mode experiment to assess the effects of using three data collection modes of administration and to determine whether ratings of outpatient/ambulatory care vary by patient characteristics.

What are the survey topics?

The survey measures patients' experiences on topics that are important when choosing an HOPD or ASC. The questions relate to facilities and staff, communication about the procedure and preparing for discharge and recovery.

What is the current status of the survey?

Voluntary national reporting program began in January 2016 and will continue until noted in future rulemaking. The current OAS CAHPS survey protocol allows for three administration modes: mail only, telephone only and mail with telephone follow up.

What is the mode experiment?

The Web mode experiment will be conducted by RTI International to investigate the feasibility of adding Web-based data collection.

The mode experiment will test mail- only, telephone- only, web- only, web with mail follow-up, and web with telephone follow-up modes of data collection. A representative sample of HOPDs and ASCs will be selected and recruited. The recruitment effort begins in January 2019; data collection is projected to begin in the Spring of 2019.

What are the benefits to participating in the mode experiment?

  1. Participation provides an opportunity to understand patients' experiences at HOPDs and ASCs.
  2. Survey findings will identify areas for improvement for participating facilities.
  3. CMS will cover the costs of implementing the Web mode experiment; RTI will prepare and mail the questionnaires, prepare and send the Web survey and conduct the telephone interviews as well as prepare summary results.
  4. At the conclusion of the study, overall de-identified frequencies of survey responses will be shared with all participating HOPDs and ASCs; aggregate results will be sent to each participating HOPD or ASC separately.

What is needed from HOPDs and ASCS for the mode experiment?

Over a period of three consecutive sample months starting Spring 2019, participating HOPDs and ASCs will provide a list of patients who had an outpatient surgery or procedure in the prior month. Patients selected from each of the three months will receive either a mail, telephone, web, or a mixed mode survey. Each data collection period, regardless of mode, will last approximately six weeks. Patients will be randomly assigned to one of the five data collection modes. The survey will be available in English and Spanish.

What patient information is needed from participating HOPDs and ASCs?

The following is a list of patient information needed:

  • Name
  • Address
  • Telephone number
  • Email Address
  • Date of birth
  • Gender
  • Date the surgery or procedure was performed
  • Level I CPT Surgery Codes (10021-69990) or the following G-codes (G0104, G0105, G0121, G0260)

Patients who have been sampled for another survey administered for the facility should be excluded from the mode experiment. RTI will work with HOPDs and ASCs or their designated vendors to facilitate this process.

What data security measures are in place?

RTI has policies, procedures, systems, and processes in place to ensure that personally identifiable information (PII) and private health information (PHI) are protected and secured at all times. We are happy to provide a letter from RTI's Privacy Officer addressing more specifically how RTI protects PII and PHI.

Are HOPDs and ASCs required by federal law to participate in the Web mode experiment?

No. Participation is voluntary. However, we hope all selected HOPDs and ASCs will participate in this study so that the general population of providers that perform outpatient surgeries and procedures is accurately and fairly represented.

What if I have additional questions about OAS CAHPS or the mode experiment?

We welcome questions and comments via our email address at or our toll- free number 1-866-590-7468 (please leave a message).