Correspondence and reprint requests to: Dr. T.M. Aslam Appt. 824 51 Whitworth St. West Manchester, England M15ED U.K. Tel.: +44 161 2364626 E-mail: TAslam@AOL.COM Abstract purpose To develop and test a questionnaire to assess quality of vision in pseudophakic patients. methods The problems with existing health measurement scales and the need for a new questionnaire are first discussed. Development of the new questionnaire from concept to completion is presented and all stages discussed. The questionnaire is then tested for internal consis- tency, reliability and validity. results The Cronbach Alpha for internal consistency was 0.92. British Standards Institution repeatability coefficient was satisfactory at 6.6. Discriminant construct validity testing by extreme groups demonstrated excellent discrimination between patients with func- tionally significant posterior capsule opacification (PCO) and no sig- nificant PCO (Mann-Whitney U test, p = 0.001). conclusion The questionnaire is validated as a robust, stable measure of pseudophakic visual symptoms with a high degree of clin- ical utility. It should be invaluable for the many studies that compare outcomes from different forms of modern cataract surgery with implantation of different intraocular lenses. Key words Pseudophakia; photopsias; questionnaire validity; visual acuity; intraocular lenses; cataract surgery; quality of life; poste- rior capsular opacification Introduction With modern cataract surgery and advanced intra- ocular lens design, patients and surgeons alike can demand a level of A new questionnaire for pseudophakes 241 Ophthalmic Epidemiology 0928-6586/04/US$ 22.00 Ophthalmic Epidemiology – 2004, Vol. 11, No. 3, pp. 241–253 DOI: 10.1080/09286580490514568 © 2004 Taylor & Francis Ltd. Accepted 20 January 2004 The development and assessment of a self- perceived quality of vision questionnaire to test pseudophakic patients T.M. Aslam D. Gilmour S. Hopkinson N. Patton P. Aspinall Princess Alexandra Eye Pavilion, Edinburgh, Scotland, U.K. Original article