ESCRS - Patient Reported Outcome Extension ;

Patient Reported Outcome Extension

The project

The aim of this project is to offer surgeons and scientists a possibility to link patient-reported outcome measures to clinical outcome data. This will enable better knowledge of indications for surgery and offer a tool for clinical improvement work based on the patients’ outcome.

The project is funded by the ESCRS

Status of the project

The Catquest-9SF questionnaire for cataract surgery is currently available with validated translations in English, German, Italian, Dutch, Spanish, Slovakian and Swedish and will soon be available in Danish. For the QIRC refractive surgery questionnaire, validated translations are available in English and Greek, while Italian, Dutch, Swedish, German, Spanish and Slovakian translations are in progress. The project is open for more languages as we find interested colleagues in other countries.

Scientific basis behind the project

Patient-centered outcomes research aims at combining patient-reported outcomes with clinical outcomes data. The goal is to improve care using both patient-reported and clinical data. To combine these data gives information on which clinical data that are related to patient satisfaction and ability to live a preferred life. It also gives information about the influence of risk factors on the self-assessed outcome. A fruitful way to analyze patient-reported outcomes and clinical outcomes is to study what signifies a diverging outcome.


Patient-reported outcomes are measured using questionnaires. The questionnaire should also be short and suitable for patient’s self-administration to streamline implementation. Patients need to fill in the questionnaire before surgery and three months after surgery. The questionnaire should be scored using Rasch analysis to provide legitimate interval scoring and constructed and validated by modern psychometric techniques.

According to a recent publication evaluating different available questionnaires, the Catquest-9SF appears to be an ideal questionnaire for cataract surgery and the Quality of Life Impact of Refractive Correction (QIRC) appears ideal for refractive surgery.

Both Catquest-9SF and QIRC are validated in several languages: Catquest-9SF: Swedish, English, German, Dutch, Italian, Spanish, Slovakian; QIRC : English, Italian, Spanish, German, Dutch, Greek. The questionnaire data should be stored in a registry linked to the EUREQUO and not in the EUREQUO registry itself for legal reasons. The questionnaire registry should contain functions for automatic evaluation of the results. The results should be linked to the output reports from the EUREQUO database. Clinics or surgeons participating in the EUREQUO database are offered the possibility to connect the patient questionnaire to their data collection of outcomes for a limited period of time. This will enable surgeons to compare with other clinics on what disability level their patients are operated on and the magnitude of improvement after surgery. Collecting data on patient-reported outcomes will also generate new information about patient satisfaction with vision and indications for cataract surgery. This will benefit both patients and surgeons.

Purpose and goal

The purpose of the EUREQUO project was to measure outcomes of cataract and refractive surgery. The original EUREQUO system was designed for measuring clinical outcome data. However, outcomes of surgery must take into account both the clinical outcome and the patient’s opinion about the outcome. Cataract surgery is usually performed as elective surgery to improve the patient’s quality of life. Therefore, the patient’s perceived benefit of surgery is as important as the clinical outcome.
When patient-reported outcome measures are connected to clinical outcome measures in cataract or refractive surgery it will be possible to identify opportunities for improvement of quality of care. It will also be possible to analyze indications for surgery and, if needed, modify the indication settings. This means for instance, that it may be possible to predict which patients that will not have benefit of surgery because they are too healthy or too poor before surgery.

Clinical workflow

Two different questionnaires will be used, one for cataract surgery – Catquest-9SF, and one for refractive surgery – QIRC. Both questionnaires are Rasch analyzed which means that they are constructed according to modern psychometric standards (Item-Response theory). Collecting data with these two questionnaires means of course that the patient has to fill in the answers of the questionnaire items.
Patient’s data can be collected in two ways; by a paper form or by a web site that the patient can log in to. At the moment the paper form model will be used.
The paper form will be presented to the patient once before surgery and then 3 months after surgery. The preoperative questionnaire can be completed by the patient during visiting the clinic. This can be done at the preoperative examination visit or on the day of surgery (before surgery!). It is important that the decision to operate is taken before the patient fills in the questionnaire. The postoperative questionnaire can be sent home to the patient together with a paid response envelope addressed to the clinic. The completed paper form has to be transcribed into the EUREQUO web form by a health care professional.

Result Interpretation

Each completed item will give an item score. The average score of all items will give a person score. The patient-reported outcome is calculated as the difference between the preoperative and postoperative person scores.

Result calculation

Each questionnaire has a raw score. The raw score is a ranking score (ordinal data) depending on what response option the patient has ticked. If for instance there are 4 response options including from the slightest problem to the greatest problem, the raw score will be 1 (slightest), 2, 3 and 4 (greatest).
The raw score will not be used for calculating the result. Instead a Rasch score will be used. The Rasch score takes into account that the items are of varying difficulty and that the distance between the response options are not equally big. The Rasch score is interval data and can be treated with parametric statistics.

Rasch scoring Reference

The EUREQUO system will provide you with a conversion table for each questionnaire.

How to participate

The PROE extension is available to all physicians documenting their Cataract and Refractive surgeries using the EUREQUO project.

Publications Catquest-9SF

Lundström M, Pesudovs K. Catquest-9SF patient outcomes questionnaire. Nine-item short-form Rasch-scaled revision of the Catquest questionnaire. J Cataract Refract Surg. 2009;35:504-513.

Gothwal VK, Wright TA, Lamoureux EL, Lundström M, Pesudovs K. Catquest Questionnaire: Re-validation in an Australian cataract population. Clin Experiment Ophthalmol 2009;37:785-794.

Harrer A, Gerstmeyer K, Hirnschall N, Pesudovs K, Lundstrom M, Findl O. The impact of bilateral cataract surgery on vision-related activity limitations. J Cataract Refract Surg. 2013 May;39(5):680-685.

Skiadaresi E, Ravalico G, Polizzi S, Lundström M, González-Andrades M, McAlinden C. The Italian Catquest-9SF cataract questionnaire: translation, validation and application. Eye and Vision 2016. 3:12 doi: 10.1186/s40662-016-0043-9

Visser MS, Dieleman M, Klijn S, Timman R, Lundström M, Busschbach JJV, Reus NJ. Validation, norm scores and test-retest for the Dutch Catquest-9SF. Acta Ophthalmol. 2016 Oct 24. doi: 10.1111/aos.13287.

Lundström M, Llovet, F, Llovet A, Martinez del Pozo M, Mompean B, González J-V, Pesudovs K. Validation of the Spanish Catquest-9SF in patients achieving a monofocal or trifocal intraocular lens. J Cataract Refract Surg 2016; 42:1791–1796.


Prof. Mats Lundström

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