The EQ-5D-3L valuation study for Bermuda: using an on-line EQ-VT protocol.

BACKGROUND: In many countries, methods of economic evaluation and Health Technology Assessment are used to inform healthcare resource allocation decisions. These approaches often require EQ-5D health outcomes measures. This study aimed to create an EQ-5D-3L value set for Bermuda from which EQ-5D-5L Crosswalk values could be obtained. METHODS: Respondents in Bermuda were recruited locally. A team of Trinidad-based interviewers with prior EQ-5D-3L valuation experience conducted valuation interviews on-line using the EQ-VT protocol. Respondents completed composite time-trade off (cTTO) and discrete choice experiment (DCE) tasks. A hybrid model that included both the cTTO and DCE data was estimated. An EQ-5D-5L crosswalk value set was then created from the EQ-5D-3L index values. Coefficients in the resulting crosswalk model were compared with those of crosswalk and valuation studies from other countries. RESULTS: The valuation tasks were completed by a near-representative sample of 366 adult Bermuda citizens. Half of the respondents reported being in state 11111. The lowest EQ VAS and EQ-5D-3L index values were 20 and - 0.120 respectively. The hybrid model produced all logically consistent and statistically significant coefficients that in turn produced index values that were very similar to those obtained in a preliminary model (MAD of 0.027). DISCUSSION: The on-line EQ-VT valuation study was successfully conducted in Bermuda and the values therein can now be used for economic analysis in Bermuda. The Bermuda values differed considerably from those of the other countries against which they were compared. Challenges were encountered with recruitment for an on-line survey in a small population.

Estimating the Health-Related Quality of Life Benefit of Prophylactic Treatment for COVID-19 in Immunocompromised People: A Multimethod Valuation Study.

Background: Pre-exposure prophylaxis (PrEP) for COVID-19 provides additional protection, beyond vaccines alone, for individuals who are immunocompromised (IC). This may reduce the need for preventative behavioral modification, such as shielding-a behavioral restriction limiting an IC individual to minimize face-to-face interactions and/or crowded places. Therefore, PrEP may improve psychosocial well-being and health-related quality of life (HRQoL) for individuals with IC conditions. Objective: To estimate the potential HRQoL and utility benefit of PrEP for prevention of COVID-19 in individuals with IC conditions who may not have an adequate response of full vaccination (and therefore are at "highest risk" of severe COVID-19) that can be used in future economic evaluations of preventative therapies against COVID-19. Methods: Vignettes describing HRQoL associated with 2 pre-PrEP states (shielding and semi-shielding behavioral restrictions) and a post-PrEP state were developed from a literature review and tested through interviews with clinicians (n = 4) and individuals with IC conditions (n = 10). Vignettes were valued by a general population sample (N = 100) using a visual analog scale (VAS), time trade-off (TTO), and EQ-5D-5L. A sample of individuals with IC conditions (n = 48) valued their current HRQoL and a post-PrEP vignette using VAS and EQ-5D-5L. Results: Individuals with IC conditions reported a mean current EQ-5D-5L score of 0.574, and 0.656 for post-PrEP based on the vignette. PrEP would lead to behavior changes for 75% (30/40) of individuals with IC conditions and an emotional benefit for 93% (37/40) of individuals with IC conditions. Mean values from the general population valuation based on EQ-5D-5L ranged from 0.606 ("shielding") to 0.932 ("post-PrEP"). Conclusion: This study quantified the expected health state utility benefit of reduced psychosocial burden and behavioral restriction. PrEP would potentially result in a utility gain between 0.082 and 0.326, dependent on valuation approach and expected change in behavioral restrictions, leading to improvements in daily activities and emotional well-being.

A Direct Comparison Between Discrete Choice With Duration and Composite Time Trade-Off Methods: Do They Produce Similar Results?

OBJECTIVES: Discrete choice experiments including a duration attribute (DCEd) represent a promising candidate method for valuing health-related quality-of-life instruments. However, it has not been established that DCEd can produce similar results as composite time trade-off (cTTO) or EuroQol Valuation Technology (EQ-VT) valuations of the EQ-5D-5L instrument. This study provides a direct comparison between cTTO and EQ-VT, and DCEd valuation methods. METHODS: An EQ-VT study was conducted in Trinidad and Tobago to value the EQ-5D-5L. 1079 respondents each completed 10 cTTO tasks and 12 discrete choice experiments tasks without a duration attribute. A separate sample of 970 respondents each completed 18 split-triplet DCEd tasks. Several regression models were applied to the EQ-VT data, and the DCEd data were analyzed using mixed logit models with an exponential discount rate. The estimated values were compared using scatterplots and Bland-Altman plots. RESULTS: The ordering of dimensions was identical in level 5 for cTTO/EQ-VT and DCEd models, with pain/discomfort being the most important dimension and usual activities being least important. cTTO/EQ-VT models produced a value for state 55555 ranging between -0.52 and -0.69, whereas this was -0.543 for the nonlinear mixed logit model for the DCEd data. Scatterplots and Bland-Altman plots suggested excellent agreement between cTTO/EQ-VT and DCEd-based estimates. CONCLUSIONS: CTTO/EQ-VT and DCEd valuations produce similar results when correcting DCEd for nonlinear time preferences. The ordering of importance of the dimensions and scale are identical, suggesting that the 2 methods measure the same construct and produce similar results.

Is anchoring at 'dead' a theoretical requirement for health state valuation?

Values that accompany generic health measures are typically anchored at 1 = full health and 0 = dead. Some health states may then be considered 'worse than dead' (WTD) and assigned negative values, which causes fundamental measurement problems. In this paper, we challenge the assumption that anchoring values at 'dead = 0' is necessary for quality-adjusted life year (QALY) estimation. We summarise the role of 'dead' in health state valuation and consider three critical questions: (i) whether the measurement properties of health state values require 'dead'; (ii) whether 'dead' needs to be valued relative to health states; and (iii) whether values for states WTD are meaningful or useful. We conclude that anchoring 0 at dead is not a requirement of health status measurement or cost-effectiveness analysis. This results from reframing QALYs as the relevant unit of measurement and reframing values as being derived from QALYs rather than the reverse.

Testing "Pits" Time Trade-Off: Can Data Quality be Improved by Removing Death From Valuation of Health States?

OBJECTIVES: Composite time trade-off (cTTO) often exhibits issues such as a value clustering at -1, potentially due to suboptimal valuation task design. We developed a novel time trade-off which uses the "pits" state as an anchor state and enables a unified time trade-off procedure for all health states (referred to as "pTTO"). This study aimed to test the pTTO for valuation of EQ-5D-5L health states. METHODS: A total of 120 members of the general public were invited to value 3 pairs of dominant/dominated EQ-5D-5L states using both cTTO and pTTO and the "pits" state using cTTO. We compared the pTTO with cTTO in terms of feasibility (interviewer-rated task-completing difficulty), acceptability (participant-reported task experience), value distribution, logical consistency, and discriminatory ability (using the standardized response mean, an effect size measure, derived from 3 pairwise comparisons of states with dominant/dominated relationship). RESULTS: The pTTO demonstrated similar feasibility to cTTO but slightly lower acceptability. The pTTO values exhibited a smoother and more continuous distribution compared with cTTO values. Relative to the cTTO, the pTTO showed higher individual-level logical consistency rate for the pairs comprising severe states (stringent criterion: 53.04% vs 17.39%; less stringent criterion: 82.61% vs 78.26%). The standardized response mean value based on pTTO values were higher than those based on cTTO values for the pair comprising severe states (0.388 vs -0.140). CONCLUSIONS: The pTTO appeared to be feasible and acceptable to value EQ-5D-5L states. The pTTO values were less clustered, more logically consistent, and discriminative compared with the cTTO values for severe health states.

A time trade-off study to determine health-state utilities of transplant recipients with refractory cytomegalovirus infection with or without resistance.

BACKGROUND: Health-state utility values (HSUVs) for post-transplant refractory cytomegalovirus (CMV) infection (with or without resistance [R/R]) were determined using a time trade-off (TTO) survey completed by 1,020 members of the UK general public. METHODS: Existing literature and qualitative interviews with clinicians experienced in treating R/R CMV were used to develop initial draft vignettes of health states. The vignettes were refined to describe three clinical states of R/R CMV: clinically significant and symptomatic (CS-symptomatic CMV); clinically significant and asymptomatic (CS-asymptomatic CMV); and non-clinically significant (non-CS CMV). Each clinical state was valued independently and combined with three events of interest: graft-versus-host disease; kidney graft loss; and lung graft loss to generate twelve vignettes. The final vignettes were evaluated by a sample of the UK general public using an online TTO survey. Exclusion criteria were applied to the final data to ensure that responses included in the analysis met pre-defined quality control criteria. RESULTS: Overall, 738 participants met the inclusion criteria and were included in the analysis. The sample was representative of the UK general population in terms of age and sex. Non-CS CMV had the highest mean HSUV (95% confidence interval) (0.815 [0.791, 0.839]), followed by CS-asymptomatic CMV (0.635 [0.602, 0.669]), and CS-symptomatic CMV (0.443 [0.404, 0.482]). CS-symptomatic CMV with lung graft loss had the lowest mean HSUV (0.289), with none of the health states considered on average worse than dead. CONCLUSIONS: Post transplant R/R CMV has substantial impact on the health-related quality of life of patients. The utility values obtained in this study may be used to support economic evaluations of therapies for R/R CMV infection.

A Methodological Study to Compare Alternative Modes of Administration With Value EQ-5D Using Preference-Elicitation Techniques.

OBJECTIVES: Time trade-off (TTO) and discrete choice experiment (DCE) preference-elicitation techniques can be administered using face-to-face interviews (F2F), unassisted online (UO) surveys, or remote-assisted (RA) interviews. The objective of this study was to explore how the mode of administration affects the quality and reliability of preference-elicitation data. METHODS: EQ-5D-5L health states were valued using composite TTO (cTTO) and DCE approaches by the UK general population. Participants were allocated to 1 of 2 study groups. Group A completed both F2F and UO surveys (n = 271), and group B completed both RA and UO surveys (n = 223). The feasibility of survey completion and the reliability and face-validity of data collected were compared across all modes of administration. RESULTS: Fewer participants reported receiving sufficient guidance on the cTTO tasks during the UO survey compared with the 2 assisted modes. Participants across all modes typically reported receiving sufficient guidance on the DCE tasks. cTTO data were less reliable from the UO survey compared with both assisted modes, but there were no differences in DCE data reliability. cTTO data from all modes demonstrated face-validity; however, the UO survey produced higher utilities for moderate and severe health states than both assisted modes. Both F2F and RA modes provided comparably reliable data. CONCLUSIONS: The reliability of DCE data is not affected by the mode of administration. Interviewer-assisted modes of administration (F2F or RA) yield more reliable cTTO data than unassisted surveys. Both F2F and RA surveys produced similar-quality data.

Estimation of health utility values for alopecia areata.

PURPOSE: Alopecia areata (AA) is an autoimmune-mediated inflammatory dermatological disease characterised by non-scarring hair loss affecting the scalp and sometimes other hair-bearing sites. This study aimed to elicit health state utility values (HSUVs) from the UK general population for AA using time trade off (TTO) interviews. METHODS: Vignette descriptions of health states defined by the extent of hair loss were developed (as well as one describing caregiver burden). These were developed using data from standardised patient reported outcome (PRO) measures, a literature review and qualitative interviews. Health states were defined based on the severity of alopecia tool (SALT), which assesses extensiveness of scalp hair loss. HSUVs were then elicited for each health state in TTO interviews with the UK public. RESULTS: One caregiver and five patient health states were developed based on the literature review findings, clinical trial PRO (Hospital Anxiety and Depression Scale and Alopecia Areata Patient Priority Outcomes Questionnaire) data and qualitative interviews with patients (N = 11), clinical experts (N = 4) and caregivers of adolescents with AA (N = 10). These data showed a more severe impact among patients with more extensive hair loss. One hundred and twenty participants evaluated the vignettes in TTO interviews. Patient HSUVs ranged from 0.502 for the most extensive hair loss health state (SALT 50-100 + eyebrow and eyelash loss) to 0.919 (SALT 0-10) for the mildest health state. The caregiver HSUV was 0.882. CONCLUSION: Quantitative and qualitative data sources were used to develop and validate vignettes describing different AA health states. Patient and caregiver HSUVs demonstrate a large impact associated with AA, especially for states defined by more extensive hair loss.

Health state utilities associated with weight loss: preferences of people with type 2 diabetes and obesity in Japan.

AIMS: Health state utilities associated with weight change are needed for cost-utility analyses (CUAs) examining the value of treatments for type 2 diabetes and obesity. Previous studies have estimated the utility benefits associated with various amounts of weight reduction in the US and Europe, but preferences for weight change in Asian cultures may differ from these published values. The purpose of this study was to estimate utilities associated with reductions in body weight based on preferences of individuals with type 2 diabetes and obesity in Japan. METHODS: Health state vignettes represented type 2 diabetes with respondents' own current weight and weight reductions of 2.5%, 5%, 7.5%, 10%, 12.5%, 15%, and 20%. Utilities were elicited in time trade-off interviews with a sample of respondents in Japan with type 2 diabetes and body mass index (BMI) ≥25 kg/m2 (the cutoff for obesity in Japan). RESULTS: Analyses were conducted with data from 138 respondents (84.8% male; mean age = 58.0 years; mean BMI = 29.4 kg/m2) from all eight regions of Japan. Utility gains gradually increased with rising percentage of weight reductions ranging from 2.5% to 15%. Weight reductions of 2.5% to 15% resulted in utility increases of 0.013 to 0.048. The health state representing a 20% weight reduction yielded a wide range of preferences (mean utility increase of 0.044). Equations are recommended for estimating utility change based on any percentage of weight reduction (up to 20%) in Japanese people with type 2 diabetes and obesity. LIMITATIONS: This study was conducted in a sample with limited representation of patients with BMI >35 kg/m2 (n = 13) and relatively few women (n = 21). CONCLUSION: Results may be used to provide inputs for CUAs examining the value of treatments that are associated with weight loss in patients with type 2 diabetes and obesity in Japan.

Assessment of health state utilities associated with adult and pediatric acid sphingomyelinase deficiency (ASMD).

INTRODUCTION: Acid sphingomyelinase deficiency (ASMD) type B is a rare genetic disorder leading to enlargement of the spleen and liver, pulmonary dysfunction, and other symptoms. Cost-utility analyses are often conducted to quantify the value of new treatments, and these analyses require health state utilities. Therefore, the purpose of this study was to estimate utilities associated with varying levels of severity of adult and pediatric ASMD type B. METHODS: Seven adult and seven child health state vignettes describing ASMD were developed based on published literature, clinical trial results, and interviews with clinicians, patients with ASMD, and parents of children with ASMD. The health states were valued in time trade-off interviews with adult general population respondents in the UK. RESULTS: Interviews were completed with 202 participants (50.0% female; mean age = 41.3 years). The health state representing ASMD without impairment had the highest mean utility for both the adult and child health states (0.92/0.94), and severe ASMD had the lowest mean utility (0.33/0.45). Every child health state had a significantly greater utility than the corresponding adult health state. Differences between adult/child paired states ranged from 0.02 to 0.13. Subgroup analyses explored the impact of parenting status on valuation of child health states. DISCUSSION: Greater severity of ASMD was associated with lower mean utility. Results have implications for valuation of pediatric health states. The resulting utilities may be useful in cost-utility modeling estimating the value of treatment for ASMD.

Disutility of Cognitive Processing Speed (CPS) Impairment in the Context of Multiple Sclerosis: A Time Trade-Off (TTO) Elicitation Study.

Introduction: Cognitive impairment, especially relating to cognitive processing speed, is a major cause of disability in people with multiple sclerosis (MS). Utility values are quantitative estimates of the quality of life experienced in specific health states and are a key component of cost-effectiveness modelling. However, existing health state utility values in MS typically focus on physical ability and are generally derived using generic (not disease-specific) measures of quality of life. The objective of the current study was to generate health state utility values for levels of cognitive impairment. We used a direct utility elicitation approach called the time trade-off (TTO) methodology. Materials and Methods: Health state descriptions were created following interviews with healthcare professionals, patients, and caregivers in the United States (n=35), and with healthcare professionals in the UK (n=5). Three health states (mild, moderate, and severe impairment) were defined based upon a well-established and validated test for cognitive dysfunction called the Symbol Digit Modalities Test (SDMT) and described using qualitative interview findings. Next, interviews with members of the general public in the UK were conducted to estimate utility values for each health state using the TTO methodology. The procedure was based on the established Measurement and Valuation of Health (MVH) protocol, which generates values on a scale from 0.0 to 1.0. Results: Mean health state utility values were 0.77 ± 0.24 in "mild impairment" (SDMT 43-40), 0.57 ± 0.26 in "moderate impairment" (SDMT 39-32), and 0.34 ± 0.28 in "severe impairment" (SDMT ≤ 31). Discussion: Results indicate that the public perceives that health states of cognitive slowing (as observed in MS) are associated with a substantial reduction in affected individuals' health-related quality of life, quantified using the TTO methodology. Future economic modeling should consider how utility impacts of both cognitive and physical disability can be appropriately incorporated.

Comparing heuristic valuation processes between health state valuation from child and adult perspectives.

OBJECTIVES: Health state valuation assumes that respondents trade off between all aspects of choice tasks and maximize their utility. Yet, respondents may use heuristic valuation processes, i.e., strategies to simplify or avoid the trade-offs that are core to health state valuation. The objective of this study is to explore if heuristic valuation processes are more prevalent for valuation from a 10-year-old child's perspective compared to the use of an adult perspective. METHODS: We reused existing data in which EQ-5D health states were valued from adult and child perspectives with composite time trade-off (cTTO) and discrete choice experiment (DCE) tasks. Our analyses focused on comparing completion time and responding patterns across both perspectives. We also explored how reflective of a set of heuristic strategies respondents' choices were in both perspectives. RESULTS: We found no evidence for systematic differences in completion time across perspectives. Generally, we find different responding patterns in child perspectives, e.g., more speeding, dominance violations, and clustering of utilities at 1.0, 0.8, and 0. Very few heuristic strategies provide a coherent explanation for the observed DCE responses. CONCLUSION: Our results provide some, albeit indirect, evidence for differences in heuristic valuation processes between perspectives, although not across all data sources. Potential effects of heuristic valuation processes, such as transfer of responsibility, may be identified through studying responding patterns in cTTO and DCE responses.

Valuing selected WAItE health states using the Time Trade-Off methodology: findings from an online interviewer-assisted remote survey.

PURPOSE: The Weight-Specific Adolescent Instrument for Economic Evaluation (WAItE) is a physical weight-specific patient reported outcome measure for use in adolescence. The purpose of this study was to use the Time Trade-Off (TTO) methodology, administered using an online interviewer-assisted remote survey, to obtain utility values for several health states from the WAItE descriptive system from a sample of the UK adult general population. METHODS: The adult sample was gathered using a market research company and a sample of local residents. All participants completed the same interviewer-assisted remote survey, which included rating WAItE states of varying impairment using the TTO. RESULTS: 42 adults completed the survey. Utility values were gathered for four health states, ranging from low impairment to the most severe health from the WAItE descriptive system (the Pits state). Consistent orderings of the WAItE health states were observed; the health state with the lowest level of impairment was valued highest and the Pits state was valued lowest. Several respondents (n = 7, 17%) considered the Pits state to be worse than death; however, the mean value of this health state was 0.23. CONCLUSIONS: The utility value of the Pits state relative to death generated from this study will be used to anchor latent values for WAItE health states generated from a Discrete Choice Experiment onto the 0 = death, 1 = full health Quality Adjusted Life Year (QALY) scale as part of a valuation study for the WAItE in the UK population. This study also provides further evidence that interviewer-assisted digital studies are feasible for collecting TTO data.

Exploring non-iterative time trade-off methods for valuation of EQ-5D-5L health states.

INTRODUCTION: The composite time trade-off (cTTO) method is used as the primary method for valuing EQ-5D-5L health states, but it requires intensive interviewer training and stringent quality control, which increases the burden of conducting cTTO studies. In this study, two non-iterative variants of the TTO method, non-stopping TTO (nTTO) and open-ended TTO (oTTO), were tested head-to-head with the cTTO method aiming to reduce the administration burden. METHODS: 31 EQ-5D-5L health states from an orthogonal array was selected and valued by a general public sample in China. Data were collected by 7 interviewers with all interviewers performed an equal number of interviews using all three TTO methods. We compared the value distribution, logical consistency, administration burden, and modeling performance of these three TTO methods. RESULTS: In total, 422 participants participated in the valuation interviews, with 139 using the nTTO method, 140 using the oTTO method, and 143 using the cTTO method. Both oTTO and nTTO methods saved around 10 min for conducting an interview. The mean values of three methods were similar with each method showed different characteristics in their value distributions. cTTO outperformed the other two methods in terms of modeling performance. DISCUSSION: Both non-iterative TTO methods showed potential for valuing EQ-5D health states, although their data distributions and modeling performance were inferior to the cTTO method. The results of this study showed the potential of these two alternative non-iterative TTO methods.

Do people with different sociodemographic backgrounds value their health differently? Evaluating the role of positional objectivity.

Objective: The fundamental disconnect between the actual and the perceived health of an individual raises considerable skepticism on the self-reported health data as it may be confounded by an individual's socio-economic status. In this light, the present study aims to assess if people with different sociodemographic backgrounds value their health differently. Methods: The health-state valuation using time-trade off was performed in a cross-sectional survey among a representative sample of 2,311 adults from India. Individuals were selected using a multistage stratified random sampling from five Indian states to elicit their present health-state, and to perform the health-state valuation exercise using computer assisted personal interviewing. A single block of standardized health-states was valued by multiple individuals, each belonging to different socio-demographic group. The difference in the valuation of health was assessed using bivariate analysis. The impact of different sociodemographic factors on the health-state valuation was evaluated using Tobit regression model. Results: Differences in the valuation of health were observed among different groups of age, religion, family type, state of residence, substance abuse, presence of ailments at the time of valuation, and number of dependent members in the household. Even after controlling for the severity of the administered health states, factors having a significant association with the valuation of health are age, religion, state of residence, substance abuse, family type, number of dependent members in the household, and presence of chronic or both acute and chronic ailments. Younger individuals place a higher value to their health as compared to their older counterparts. As compared to a healthy individual, a person with ailments rates the same health-state as worse. Conclusion: Inequalities in self-reported ill-health cannot be attributed to positional objectivity; age, religion, state of residence, substance abuse, family type, dependents, and ailments impact individual health valuation.

Quantifying health utilities of young adult orthodontic patients using the time trade-off method: a cross-sectional study

ABSTRACT Objective: To study the feasibility of time trade-off (TTO) method in quantifying health utility ratings in different types of malocclusion. Material and Methods: In this cross-sectional study, 70 orthodontic patients aged 18 years or above, reporting for treatment/consultation, were included and interviewed. Malocclusion-related health utilities were assessed through the TTO method, and oral health-related quality of life was measured with the help of Orthognathic Quality of Life Questionnaire (OQLQ). Angle's classification of malocclusion was recorded. Bivariate analyses and multivariate Poisson's regression were done to find out an association between the oral health utility values, OQLQ and demographic and clinical characteristics. Results: Patients with skeletal Class III malocclusion had lower health utility values than those with Class I and Class II malocclusions (p=0.013). Poisson's regression showed that Angle's Class II division 1 (0.90, CI 0.84 to 0.97), Class III (0.68, CI 0.59 to 0.95) and Skeletal malocclusion (0.79, CI 0.71 to 0.87) and OQLQ scores (1.0, CI 1 to 1.003) were found to be significant predictors of TTO utility scores. Conclusions: TTO utilities were found to be valid and well correlated with clinical findings. Health utilities could serve as useful and reliable markers of health-related quality of life (HRQL) among individuals or communities and help cost-effective preventive or intervention programs planning.

RESUMO Objetivo: Estudar a viabilidade do método Time trade-off (TTO) para quantificar escores de valoração da saúde em diferentes tipos de má oclusão. Material e Métodos: Neste estudo transversal, foram incluídos e entrevistados 70 pacientes ortodônticos com idade igual ou superior a 18 anos, que compareceram para tratamento/consulta. A valoração da saúde em relação à má oclusão foi avaliada por meio do método TTO e a qualidade de vida relacionada à saúde bucal foi medida com a ajuda do Questionário de Qualidade de Vida Ortognática (Orthognathic Quality of Life Questionnaire, OQLQ). A classificação da má oclusão segundo Angle foi registrada, e análises bivariadas e regressão multivariada de Poisson foram feitas para verificar qualquer associação entre os escores de valoração da saúde bucal, OQLQ e características demográficas e clínicas. Resultados: Os pacientes com má oclusão esquelética de Classe III apresentaram escores de valoração da saúde mais baixos do que aqueles com má oclusão de Classe I e Classe II (p=0,013). A regressão de Poisson mostrou que a Classe II de Angle divisão 1 (0,90, IC 0,84 a 0,97), Classe III (0,68, IC 0,59 a 0,95), má oclusão esquelética (0,79, IC 0,71 a 0,87) e os escores do OQLQ (1,0, IC 1 a 1,003) foram considerados preditores significativos dos escores de valoração pelo método TTO. Conclusões: Os escores do TTO foram considerados válidos e bem correlacionados com os achados clínicos, e podem servir como marcadores úteis e confiáveis da qualidade de vida relacionada à saúde (health-related quality of life, HRQL) entre indivíduos ou comunidades, e ajudar no planejamento de programas de prevenção ou de intervenção, com uma boa relação custo-benefício.

Assessment of vision-related quality of life in Chinese glaucoma patients by utility analysis / 中华实验眼科杂志

BackgroundThe influence of glaucoma on the quality of life in patients is of increasing concern for ophthalmologists in recent years. However,some studies demonstrated that different types of questionnaires about quality of life have various disadvantages. Therefore, to accurately and fully assess the influencing factors of quality of life in glaucoma patients is very important. ObjectiveThe present study was to survey the self-reported visionrelated quality of life(QOL) in glaucoma patients by means of utility analysis and to tentatively analyze its influencing factors. Methods Patients with glaucoma were recruited from a single tertiary ophthalmic department. Standard face-to-face interviews were conducted. Utility values of linear rating scale ( RS ) and time trade-off ( TTO ) were calculated to evaluate the self-reported vision-related QOL of the patients. The correlations of the utility values with the patients' general and ophthalmologic characteristics were also analyzed. This survey was approved by the Ethic Committee of Beijing Tongren Hospital. Oral informed consent was obtained from the subjects before the study.ResultsA cross-sectional study was designed. A total of 86 glaucoma patients were enrolled in this study with 62 male and 24 female, with a mean age of 44. 67 years old. The mean utility values measured by RS and TTO were 0. 62± 0. 19 and 0. 77 ± 0. 12, respectively, and no evidential correlation was found between these two values ( r =0. 074, P=0. 499 ). The RS value was associated with daily visual acuity,mean deviation(MD) of visual field and the history of trabeculectomy. Neither daily visual acuity nor MD showed a significant correlation with the TTO value. Age, work status and educational background contributed to higher utility value for the TTO method. After adjusting for age, work status and educational level,patients with visual acuity in the worse-seeing eye better than 0. 3 showed a higher TTO value than those with less than 0. 3. Conclusions Utility analysis possesses the advantages of convenience and sensitivity. RS utility value is easily affected by the Objective visual status and surgery history in glaucomatous patients,which reflects the subjective assessment of patients'visual quality. However, TTO value is primarily associated with age,work status and education level rather than visual function in glaucoma patients,which is therefore subjective assessment of the disease-related quality of life. These Results indicate that visual function impairment is not a determining factor for the QOL of glaucoma patients.