What is PROWL?
The goal of the FDA’s PROWL (Patient Reported Outcomes with LASIK) studies was to validate a new questionnaire that gives patients an accurate and complete way to report their experience with vision and LASIK. The questionnaire – a first – provides a better, more consistent collection of the patient’s reporting of visual symptoms, dry eye symptoms, as well as patient satisfaction after LASIK, overall satisfaction with vision, daily functioning and well being.
“The PROWL studies are important,” said American Society of Cataract and Refractive Surgery President Kerry D. Solomon, M.D. “This is the first scientifically validated patient questionnaire for LASIK and it has a lot of potential. It provides not only an entirely new set of data that we hope will provide more insights on LASIK outcomes for patients, but also a platform for better patient education and, ultimately, more educated decisions about vision correction. With time and use of the questionnaire, surgeons will get accurate and consistent information from the patient’s perspective.”
What was learned from the LASIK PROWL Studies and why it matters?
First, the FDA PROWL studies acknowledge the body of clinical evidence confirming the safety and effectiveness of LASIK. With that knowledge, the study’s authors wanted to further explore the patient experience with LASIK, including reports of visual and ocular symptoms and satisfaction with vision and LASIK. Their findings suggested that with a valid questionnaire, patients more accurately assess and report symptoms and satisfaction.
In order to test the performance of the questionnaire – validate it from a scientific perspective – two small sample populations of LASIK patients were given the survey of patient reported outcome (PRO) questions.
- PROWL-1 was conducted at a military center with 262 active-duty Navy personnel (ages 21-52 years of age).
- PROWL-2 had 312 civilian participants (ages 21-57 years of age) located at five private practice and academic centers around the country.
The observational study focused on the functionality of the questionnaire. However, as a result of the LASIK procedures being performed, some additional data was reported:
- Both groups reported high satisfaction rates, between 96 and 99 percent
- A small but significant subset of patients – those without symptoms prior to LASIK – experienced new visual symptoms such as glare, halos, or starbursts, or mild, moderate, or severe dry eye symptoms, 3 months after surgery.
- Overall, the prevalence of visual symptoms and dry eye decreased after having LASIK and improved over time.
- Through the questionnaire, very few patients reported their symptoms impacted their daily activities or well-being.
Has our understanding of LASIK side effects changed?
From a clinical perspective, absolutely not. LASIK side effects are well-known and understood through a huge volume of research. However, what is significant is that patient reported methods offer an entirely new set of data for clinicians and researchers to tap into. This helps to characterize the experience with LASIK more broadly and, perhaps, more accurately moving forward.
Side effects from LASIK are rare, recent studies suggest fewer than 2 percent of patients undergoing modern LASIK report symptoms. This relatively low percentage of patients experience side effects during the recovery and healing process and these include dry eye and visual symptoms such as glare, halos and starbursts. Typically, these symptoms resolve with time or, occasionally, with additional treatment. In particular, those patients who choose to have the most advance treatment profiles with the latest technologies have been shown to have higher levels of satisfaction with the procedure.
“As we have said many times before, LASIK is surgery and can produce post-operative effects,” said Dr. Solomon. “Factors such as the patient’s expectations and understanding of LASIK have an important bearing on outcomes. It’s also true that not all people who undergo LASIK are good candidates for the procedure. The ultimate key to steady improvement in LASIK outcomes is patient education, effective counseling before and after the procedure, and effective screening to make sure that people who undergo LASIK are good candidates. LASIK is one of many vision correction options, and patients should choose and be guided toward the options that are right for them.”
Importantly, doctors want to thoroughly understand those patients who do experience symptoms and the PRO questionnaire may well represent an important advancement in accurately reporting and characterizing symptoms.
The PRO Questionnaire
The PROWL survey instrument consists of more than 68 questions intended to help patients self-assess and report a range of issues including, satisfaction with current vision, satisfaction with LASIK surgery, and the existence, bothersomeness, and effect on usual activities of visual symptoms including: double images, glare, halos and starbursts. The questionnaire incorporates both written definitions of symptoms and images to help illustrate the symptom and severity levels. The baseline FDA PROWL questionnaire took study participants on average of 20 minutes to complete.
So, what’s the bottom line?
The PROWL studies affirm an ongoing commitment to careful, thorough patient counseling about the risks for side effects and symptoms from LASIK. Using validated questionnaires, such as the one created for the PROWL study, is an excellent vehicle for collecting accurate and consistent information from patients. LASIK practices will have access to the PROWL questionnaire and should strongly consider incorporating its use as it may allow eye care professionals and patients to make more educated decisions about vision correction. If you are among the thousands of people considering vision correction options, you owe it to yourself and your vision to become as informed as possible about LASIK and other procedures. If you are reading this, you have found the ARSC Insight blog and we encourage you to subscribe.
Read more from the FDA here.