Effect of hospital on variation in visual acuity and vision-specific quality of life after cataract surgery Jose M. Quintana PhD, 1 Antonio Escobar PhD, 2 Amaia Bilbao MSc, 3 Gemma Navarro PhD, 4 Jose M. Begiristain PhD, 5 Nerea Fernandez de Larrea MD, 6 Emilio Perea PhD, 7 Txomin Alberdi, MD 8 and the IRYSS Cataract Group* 1 Professor, Chief of Service, Unidad de Investigación, Hospital Galdakao-Usansolo-CIBER Epidemiología y Salud Pública (CIBERESP), Galdakao, Vizcaya, Spain 2 Epidemiologist, Unidad de Investigación, Hospital de Basurto-CIBER Epidemiología y Salud Pública (CIBERESP), Bilbao, Vizcaya, Spain 3 Biostatistician, Fundación Vasca de Innovación e Investigación Sanitarias-(BIOEF)-CIBER Epidemiología y Salud Pública (CIBERESP), Sondika, Vizcaya, Spain 4 Epidemiologist, Unidad de Epidemiologia Clinica, Corporacio Parc Tauli, Barcelona, Spain 5 Epidemiologist, Direccion Territorial de Sanidad, San Sebastián-Donostia, Guipúzcoa, Spain 6 Epidemiologist, Agencia Lain Entralgo, Madrid, Spain 7 Epidemiologist, Hospital Costa del Sol-CIBER Epidemiología y Salud Pública (CIBERESP), Marbella, Malaga, Spain 8 Specialist, Servicio de Oftalmología, Hospital Galdakao-Usansolo, Galdakao, Vizcaya, Spain Keywords cataract extraction, outcomes assessment, phacoemulsification, variation Correspondence Dr José M. Quintana Unidad de Investigación Hospital Galdakao-Usansolo Barrio Labeaga s/n, 48960 Galdakao, Vizcaya Spain E-mail: josemaria.quintanalopez@osakidetza.net Accepted for publication: 3 December 2008 doi:10.1111/j.1365-2753.2009.01157.x Abstract Objective To evaluate the contribution of hospital-to-hospital variability in changes in clinical and health-related quality of life outcomes among patients undergoing cataract extraction by phacoemulsification. Methods Prospective observational study of 14 public hospitals. We recruited consecutive patients on waiting lists for cataract extraction. Clinical data were collected prior to the intervention and 6 weeks afterward. Subjects completed the visual function index (VF-14) prior to the procedure and 3 months afterward. Univariate and multivariate analysis were performed for visual acuity and VF-14 scores. Results Substantial differences were observed across the 14 hospitals. At baseline, mean visual acuity ranged from 0.16 to 0.34, and mean VF-14 scores ranged from 48.06 to 75.89. Following cataract extraction, the mean improvement in visual acuity ranged from 0.35 to 0.57 and in VF-14 scores from 10.94 to 41.70. The ranges were even more pronounced among patients with low visual acuity or low VF-14 scores prior to the intervention. Significant differences remained in multivariate analysis. Within the multivariate analysis, the variable ‘hospitals’ had an R 2 of 0.069 for the visual acuity model and of 0.073 for the VF-14 model, 20% and 13%, respectively, of the total variability explained.Variation was also observed within geographic regions. Conclusions Outcomes of patients undergoing cataract extractions vary widely from hos- pital to hospital, even within the same geographic region, explaining an important part of the results. Quality improvement efforts should concentrate on patients with low pre- intervention visual acuity or vision-related disability to reduce this variability in outcomes. *The IRYSS Cataract group included the following co-investigators: Dr Jesús Martínez-Tapias, Dr Eduardo Aguayo (Hospital Universitario Virgen de las Nieves, Granada); Dr Juan Ramón Lacalle (Universidad de Sevilla); Dra Marisa Baré (Corporació Sanitaria Parc Taulí, Sabadell); Dra Elena Andradas, Dr Juan Antonio Blasco (Agencia Laín Entralgo, Madrid); Inmaculada Arostegui [Departamento de Matemática Aplicada, UPV-CIBER Epidemiología y Salud Pública (CIBERESP)]; Berta Ibáñez [Fundación Vasca de Innovación e Investigación Sanitarias-CIBER Epidemiología y Salud Pública (CIBERESP)]; Dra Belén Elizalde (Dirección Territorial de Gipuzkoa); Dra Idoia Garai (Dirección Territorial de Bizkaia); Dr Felipe Aizpuru [Unidad de Investigación del Hospital de Txagorritxu-CIBER Epidemiología y Salud Pública (CIBERESP) Alava]; Susana García, Nerea Gonzalez, Iratxe Lafuente, Urko Aguirre [Unidad de Investigación del Hospital Galdakao-Usansolo-CIBER Epidemiología y Salud Pública (CIBERESP), Bizkaia]. Journal of Evaluation in Clinical Practice ISSN 1356-1294 © 2010 Blackwell Publishing Ltd, Journal of Evaluation in Clinical Practice 16 (2010) 665–672 665