Validity and reliability of the Cataract TyPE pec: an intrument for meauring outcome of cataract extraction

Purpoe To deign and validate a urvey intrument that meaure viion-related functional tatu, which i appropriate for elf-adminitration in a clinical practice and mail urvey etting. Deign Obervational, validation tudy in equential patient. Method A prototype viual function intrument (the Cataract TyPE pec) wa developed baed on focu group input and then validated in an outcome tudy conducted among 1,823 patient who underwent cataract extraction performed by 22 urgeon at ix center in the United tate. Reliability wa determined by calculating Cronbach α for different type of adminitration (elf-adminitration at the ite of care and mailed urvey) and acro race and gender. Criterion validity wa determined by correlating core on the TyPE pec with baeline meaure and change in viual acuity, overall rating of viion, and general quality of life. Reult The intrument wa internally valid (Chronbach α = 0.94), both on elf-adminitration in the patient care etting and upon mailed urvey adminitration and acro patient race and gender. The TyPE pec core wa highly correlated with overall rating of viion (r = .54, P < .0001) and moderately correlated with nellen acuity (r = .32, P < .0001), rating of viion in the better eye (r = .42, P < .0001), and quality of life, a meaured by the phyical component ummary core of the F-36 (r = .27, P < .001). Change in TyPE pec imilarly correlated with change in rating of viion overall, change in bet-corrected nellen acuity, and change in rating of viion in the operated eye. Concluion The cataract TyPE pec intrument wa found to be equally valid and internally conitent when adminitered in the patient care etting and by mail urvey