Optimization And Evaluation Of Vision-related Quality Of Life Measurement Tools

Objective: To validate the Chinese-version Low Vision Quality of Life questionnaire(CLVQOL)via Rasch Analysis in Chinese population and investigate the CLVQOL as an instrument for obtaining minimal clinical important changes after cataract surgery.In oreder to determine which utility value assessment method is more suitable to evaluate quality of life changes due to dry eye symptoms.Then evaluate the long-term changes in dry eye symptoms and vision-related quality of life(VRQo L)in age-related cataract patients after phacoemulsification.Methods: 1.Qualified community residents in Shanghai were recruited and their demographic information and visual acuity were collected.Psychometric properties of the CLVQOL were tested using Rasch Analysis,including unidimentionality,person separation index(PSI),person reliability(PR),outfit MNSQ,and differential item functioning(DIF),etc.2.Patients underwent cataract surgery in Shanghai General Hospital,Shanghai Jiao Tong University,who fit the inclusion criteria were recruited.Two CLVQOLs were administered,including a preoperative CLVQOL and a CLVQOL at the end of the 3 months follow-up period,and were completed using face-to-face interviews or phone interviews conducted by trained investigators.The minimal clinically important difference(MCID)was calculated using an anchor-based method and a distribution method.3.Dry eye outpatients with a presenting visual acuity of 20/25 or better in the worse-seeing eye were recruited from the Department of Ophthalmology,Shanghai General Hospital,Shanghai Jiao Tong University.Presenting distance visual acuity,tear film break-up time(BUT),Schirmer I test(SIt)and fluorescein(FI) were assessed.The severity of dry eye symptoms was assessed using the Ocular Surface Disease Index(OSDI),and utility values were measured using the time trade-off(TTO),standard gamble(SG1,SG2)and RS methods.Different utility values were compared with each other.The most appropriate utility value method to evaluate quality-of-life changes solely due to dry eye symptoms is determined by calculating the correlation between OSDI score and different utility values.4.Cataract patients after phacoemulsification combined with IOL implantation(Ph-IOL)in one eye were enrolled.Visual acuity,BUT and SIt were measured before and 1,3,and 6 months after surgery.OSDI scores were used to evaluate the severity of dry eye symptoms.Utility values were also assessed.Results: 1.The first scale of the original CLVQOL was found to be multidimensional,and was divided into 2 scales.Then a new 5-scale CLVQOL was developed and all 5 scales were proved to be unidimensional.No notable DIF was found for all 25 items across different age or gender subgroups.2.Statistically significant positive changes in the CLVQOL scores indicated significant improvement of vision related quality of life after cataract surgery.With the larger value between the two results as the final value,the MCID values of the CLVQOL were 7.63.3.The utility scores measured with TTO,SG1,SG2 and RS were 0.95 ±0.11,0.96 ± 0.10,0.99 ± 0.07 and 0.89 ± 0.10,respectively.The utility scores evaluated by the TTO,SG1,SG2 and RS methods were significantly different from each other(p < 0.05).Only the utility scores measured with RS were significantly correlated with the composite OSDI score,“environmental trigger” and “eye discomfort” section scores(p <0.05).4.The Log MAR VA in the operated eye increased after Ph-IOL,approaching a peak at 3 months(0.26±0.15).The BUT and SIt results decreased one month after surgery and gradually recovered until 6 months.OSDI scores increased significantly after surgery and gradually decreased until 6 months.Utility values measured with TTO,SG2 or RS correlated significantly(p < 0.05)with VA and OSDI scores pre-and postoperatively.Conclusions: All items demonstrated acceptable fit to the Rasch analysis and anew 5-scale CLVQOL was developed,and it is proved to be reliable and valid.CLVQOL scores are appropriate instruments for obtaining clinically important changes after cataract surgery.This study is an effective exploration for establishing cataract surgery efficacy standards,which helps clinical and scientific research workers in ophthalmology to gain a more in-depth understanding when using CLVQOL.RS is more sensitive than TTO and SG for the evaluation of altered quality of life due to dry eye symptoms.Dry eye symptoms persist more than 3 months after Ph-IOL.Utility values were negatively influenced by dry eye symptoms.