The economic value added (EVA) resulting from medical care of functional amblyopia, strabismus, (pathologies of binocular vision) and asthma.

INTRODUCTION: Value analysis in health care calculates the economic value added (EVA) that results from improvements in health and health care. Our purpose was to develop an EVA model and to apply the model to typical and hypothetical (instantaneous and perfect) cures for amblyopia, surgical strabismus and asthma, as another, but non-ophthalmological disease standard for comparison, in the United States. METHODS: The model is based on changes in utility and longevity, the associated incremental costs, and an estimate of the value of life. Univariate sensitivity analyses were performed to arrive at a plausible range of outcomes. RESULTS: For the United States, the EVA for current practice amblyopia care is 12.9B dollars (billion) per year, corresponding to a return on investment (ROI) of 10.4% per yr. With substantial increases in investment aimed at maximal improvement ("perfect cure"), the EVA is 32.7B per yr, with ROI of 5.3% per yr. The EVA for typical surgical strabismus care is 10.3B per yr. A perfect cure may yield EVA of 9.6B per yr. The EVA for asthma is 1317B per yr (ROI 20.4% per yr.., while a perfect cure may yield EVA of 110 B per yr. Sensitivity analysis demonstrated the relatively large effects of incidence, utility, and longevity, while incremental costs have a relatively minor effect on the EVA. CONCLUSION: The economic value added by improvements in patient-centered outcomes is very large. Failing to make the necessary investments in research, prevention, detection, prompt treatment and rehabilitation of these diseases, at virtually any conceivable cost, appears economically, medically, morally and ethically deficient and consequently wasteful at very least economically for our society.

Evidence-based medicine: the value of vision screening.

OBJECTIVE: To review the literature for evidence-based medicine (EBM), to assess the evidence for effectiveness of vision screening, and to propose moving toward value-based medicine (VBM) as a preferred basis for comparative effectiveness research. METHODS: Literature based evidence is applied to five core questions concerning vision screening: (1) Is vision valuable (an inherent good)?; (2) Is screening effective (finding amblyopia)?; (3) What are the costs of screening?; (4) Is treatment effective?; and (5) Is amblyopia detection beneficial? RESULTS: Based on EBM literature and clinical experience, the answers to the five questions are: (1) yes; (2) based on literature, not definitively so; (3) relatively inexpensive, although some claim benefits for more expensive options such as mandatory exams; (4) yes, for compliant care, although treatment processes may have negative aspects such as "bullying"; and (5) economic productive values are likely very high, with returns of investment on the order of 10:1, while human value returns need further elucidation. CONCLUSION: Additional evidence is required to ascertain the degree to which vision screening is effective. The processes of screening are multiple, sequential, and complicated. The disease is complex, and good visual outcomes require compliance. The value of outcomes is appropriately analyzed in clinical, human, and economic terms.

Cost-utility analysis of screening and laser treatment of retinopathy of prematurity.

PURPOSE: Retinopathy of prematurity (ROP) is a major cause of lifelong blindness beginning in infancy. Utility analysis is used to describe the effect of illness and medical intervention on an individual's quality of life during the course of a lifetime. In this study, cost-utility analysis is used to evaluate the cost-effectiveness of both screening and laser photoablation for ROP. METHODS: Data from 2 neonatal intensive care units were recorded for infants screened and treated for ROP between March 4, 2004, and January 5, 2006. The cost model was developed using procedures classified by Current Procedural Terminology and the costs paid for by the Centers for Medicare and Medicaid Services for 2006. Visual acuities were obtained from 10-year post-laser data and from the 10-year post-CRYO-ROP untreated cohort. RESULTS: During the study period, 515 infants received screening and treatment for ROP. They required a mean 3.4 exams per infant; 11.2% received laser photoablation. Mean visual acuities were 0.5 (Snellen 20/40) for laser-treated eyes and 0.20 (Snellen 20/100) for those who did not receive treatment. The cost-effectiveness of screening and laser photoablation of ROP in 2006 is $650/quality-adjusted life years. When discounted 3% per year for the time value of money, the cost is $1,565/ quality-adjusted life years. CONCLUSIONS: The screening and laser photoablation of ROP continue to be extremely cost-effective medical interventions.

Anterior and nasal transposition of the inferior oblique muscles in patients with missing superior oblique tendons.

INTRODUCTION: Patients with missing superior oblique (SO) tendons present with overelevation/underdepression in adduction. Unilateral cases often exhibit abnormal head postures, whereas in bilateral cases, there may be a marked V-pattern with upgaze exotropia. These patients may have craniosynostosis. METHODS: Nine children with unilateral (n = 2) or bilateral (n = 7) absent SO tendons underwent anterior and nasal transposition of the inferior oblique (IO) muscles, some in combination with horizontal rectus recession for horizontal strabismus. They were evaluated 6 to 46 months postoperatively for alignment and oculomotor examination. Cyclodeviations were not evaluated in most children. RESULTS: Postoperatively, all patients improved. Both unilateral cases were orthotropic with no abnormal head posture. In the bilateral cases, vertical deviation in adduction and exotropia in upgaze had largely cleared, although some symptoms remained, most notably vertical deviation in side gaze (3 patients) and V-pattern esotropia in downgaze (2 patients). A patient missing both SO tendons as well as the left superior rectus muscle, who had the anterior and nasal transposition on the right side only, remained with 25(Delta) left hypotropia. CONCLUSIONS: Anterior and nasal transposition of the IO muscle reduces overelevation in adduction and helps eliminate or reduce divergence of the eyes in upgaze, but esodeviation may persist in downgaze. This procedure was most effective in unilateral absence of the SO tendon. It is likely to benefit patients with severe congenital fourth nerve palsy in which standard IO muscle weakening procedures have been ineffective.

The Amblyopia and Strabismus Questionnaire: English translation, validation, and subscales.

PURPOSE: To establish the English-language version of the Amblyopia and Strabismus Questionnaire (ASQE). DESIGN: Prospective cohort study. METHODS: A structured translation process was followed to generate the ASQE, a 26-item instrument (originally in Dutch) containing five subscales for fear of losing the better eye, distance estimation, visual disorientation, double vision, and social contact and appearance. The ASQE was administered to 150 adults in a private practice setting. All had strabismus with or without amblyopia and visual acuity of 20/50 or better in at least one eye. Subjects also completed a brief disability questionnaire, and they were further characterized by levels of unilateral vision loss, diplopia, and asthenopia. RESULTS: ASQE scores were highly correlated with the disability questionnaire outcomes (r = -.76, P < .0001). Internal consistency reliability (Cronbach alpha) of the subscales ranged from 0.80 to 0.92. Strong correlations were found between clinical characteristics and the ASQE (total score and subscale scores). CONCLUSIONS: The ASQE showed good psychometric properties that are in line with those of the original instrument. This, combined with strong correlations between ASQE scores and clinical characterization of the participants, establishes the ASQE as a useful tool for use in populations with strabismus and/or amblyopia.

The cost utility of strabismus surgery in adults.

PURPOSE: Cost-utility analysis evaluates the cost of medical care in relation to the gain in quality-adjusted life years (QALYs). Our purpose was to develop a cost model for surgical care for adult strabismus, to estimate the mean cost per case, to determine the associated gain in QALYs, and to perform cost-utility analysis. METHODS: A cost model incorporated surgery, pre- and postoperative care, and a mean of 1.5 procedures per patient. The gain in QALYs was based on the improvement of utility on a scale from 0 (death) to 1 (perfect health). Utility was measured through physician-conducted interviews employing a time tradeoff question (seeking to estimate the portion of life expectancy a patient would be willing to trade for being rid of disease and associated effects). The interviews were conducted before and 5 to 8 weeks after surgery in 35 strabismic patients (age 19-75 years). RESULTS: The cost model resulted in an estimated total cost of 4,254 dollars per case. A significant improvement of utility was found: 0.96 +/- 0.11 postoperatively versus 0.85 +/- 0.20 preoperatively (p = 0.00008). Based on the mean life expectancy (36.0 years) of these patients, and discounting outcomes and costs by 3% annually, this resulted in a mean value gain of 2.61 QALYs after surgery and a cost-utility for strabismus surgery of 1,632 dollas/QALY. CONCLUSIONS: In the United States, treatments <50,000 dollars/QALY are generally considered "very cost-effective." Strabismus surgery in adults falls well within this range.

The burden of age-related macular degeneration: a value-based analysis.

PURPOSE OF REVIEW: The quality-of-life loss and the financial consequences associated with age-related macular degeneration are assessed. RECENT FINDINGS: The quality-of-life loss associated with macular degeneration is markedly underestimated by the general public, nonophthalmic physicians, and ophthalmologists who treat patients with this condition. Mild age-related macular degeneration causes a 17% decrement in the quality of life of the average patient, similar to that encountered with moderate cardiac angina or symptomatic human immunodeficiency virus syndrome. Moderate age-related macular degeneration causes a 40% decrease in the average patient's quality of life, similar to that associated with severe cardiac angina or renal dialysis. Very severe age-related macular degeneration causes a large 63% decrease in the average patient's quality of life, similar to that encountered with end-stage prostatic cancer or a catastrophic stroke that leaves a person bedridden, incontinent and requiring constant nursing care. The return on investment is high for both treatment with current age-related macular degeneration therapies and the research costs invested in the development of age-related macular degeneration treatment modalities. SUMMARY: Age-related macular degeneration is a major public health problem that has a devastating effect upon patients and marked adverse financial consequences for the economy.

The management of strabismus in adults--III. The effects on disability.

INTRODUCTION: This is the third article in a series on the various facets of the management of strabismus in adults. Here, we give a broad overview of the types and severity of disability and provide initial validation of an instrument (questionnaire) to assess these disability aspects. METHODS: After undergoing strabismus surgery, 101 patients from 6 centers completed a 6-item questionnaire in which they rated both the before-surgery and after-surgery severity of problems associated with their strabismus, ranging from specific health, daily functioning, social interaction, concerns about the future, and self-image to job-related difficulties. RESULTS: The before-surgery outcomes showed significant variation across the 6 types of problems (P < 0.001), with "specific health" and "daily tasks" yielding the highest problem rating. Patients with diplopia reported more severe problems with "daily tasks" (P = 0.004) and "concerns about the future" (P = 0.026) than patients without diplopia. Overall, all problem ratings declined after surgery (P < 0.001), but patients who were not successfully aligned were left with higher problem ratings on "specific health" (P = 0.005), "daily tasks" (P = 0.003), and "social interaction" (P = 0.024). CONCLUSIONS: The results indicate a wide range of disability aspects in adult patients with strabismus, with moderate differences between patients with or without diplopia. Improvements in disability after surgery, as reflected by these ratings, should be taken into account when assessing the health value of adult strabismus management.

The cost-utility of photodynamic therapy in eyes with neovascular macular degeneration--a value-based reappraisal with 5-year data.

PURPOSE: To assess the value conferred by photodynamic therapy (PDT) and the cost-utility of PDT for the treatment of classic, subfoveal choroidal neovascularization associated with age-related macular degeneration (ARMD). DESIGN: Average cost-utility analysis utilizing clinical trial data, patient-based time tradeoff utility preferences, and a third party insurer cost perspective. METHODS: Five-year visual acuity data from the TAP (Treatment of Age-related Macular Degeneration With Photodynamic Therapy) Investigation were modeled into a 12-year, value-based, reference case, cost-utility model utilizing year 2004 Medicare costs and an outcome of dollar/QALY (dollars/quality-adjusted life-year). Discounting of outcomes and costs using net present value analysis with a 3% annual rate was performed as recommended by the Panel for Cost-Effectiveness in Health and Medicine. RESULTS: PDT with verteporfin (Visudyne) dye for classic subfoveal choroidal neovascularization confers an 8.1% quality of life (value) improvement over the 12-year life expectancy of the reference case, while during the last 8 years the value improvement is 9.5%. The average cost-utility of the intervention is dollar 31,103/QALY (quality-adjusted life-year). Extensive one-way sensitivity analysis values range from dollar 20,736/QALY if treatment efficacy is increased by 50% to dollar 62,207 if treatment efficacy is decreased by 50%, indicating robustness of the model. CONCLUSIONS: PDT using verteporfin dye to treat classic subfoveal choroidal neovascularization is a very cost-effective treatment by conventional standards. The marked improvement in cost-effectiveness compared with a previous report results from the facts that the treatment benefit increasingly accrues during 5 years of follow-up while the number of yearly treatments diminishes markedly during that time.

Screening for amblyopia in preverbal children with photoscreening photographs: IV. Interobserver variability in photograph grading: origin and method of reduction.

BACKGROUND: Earlier detection of childhood vision disorders is a prominent goal of vision screening. The Medical Technology and Innovation (MTI) PhotoScreener addresses this objective. Use of this camera does not require verbal feedback and may be administered early in a child's development. Decreasing the variability in photograph grading results will boost the utility of any photoscreening system. This report aims to understand and to decrease intra- and inter-observer variability in grading photoscreening photographs. METHODS: We dissected the photograph grading process and quantified the intra- and inter-observer agreement using intraclass plot correlation coefficients. We evaluated the outcome of a two grader verification system vs. adjudicated measurements with Receiver Operator Characteristic (ROC) curves. PARTICIPANTS: Data on 955 children under 5 years of age, normal except for refractive error, each with complete photoscreening and eye examination data, culled from two previous studies. MAIN OUTCOME MEASURES: Intra- and inter-observer agreement in measuring bright crescent dimensions and pupillary diameters. Sensitivity and specificity of detection of hyperopia. RESULTS: Measurements of bright crescents are associated with greater variability than are measurements of pupillary diameters. Recognition and omission of light "rim" measurements from photograph grading will result in superior inter-observer agreement. Photograph independent errors increase variability and may be corrected by remeasurement. A verification system in which the most discrepant 5% of measurements are redone results in ROC curves similar to adjudicated dimension. CONCLUSIONS: We conclude: 1) two novices grading photographs can do as well as one expert in most cases; 2) the proposed grading methodology has undergone statistical validation and can be used in other areas of ophthalmology and medicine; and 3) inter-observer variability, one of the limitations of photoscreening photograph grading, can be reduced. For 95% of the photographs, two novices achieve similar true positive and true negative values with or without adjudication.

Age-related macular degeneration: economic burden and value-based medicine analysis.

It can be estimated that 17,100 new cases of neovascular (wet) AMD and 180,000 new cases of geographic-atrophy (dry) AMD occur in Canada annually. In addition to having a devastating effect on patients' lives, the condition causes significant adverse consequences for the economy. The deleterious effect of AMD on quality of life is markedly underestimated by ophthalmologists who treat patients with AMD, by non-ophthalmic physicians and by the public. In fact, patients with different degrees of severity of AMD have a perceived impairment of their quality of life that is 96% to 750% greater than the impairment estimated by treating ophthalmologists. Mild AMD causes a 17% decrease in the quality of life of the average patient, a decrease similar to that encountered with symptomatic human immunodeficiency virus infection or moderate cardiac angina. Moderate AMD produces a 40% decrease in quality of life, a decrease similar to that associated with permanent renal dialysis or severe cardiac angina. Very severe AMD causes a 63% decrement in quality of life, a decrease similar to that encountered with advanced prostatic cancer with uncontrollable pain or a severe stroke that leaves a person bedridden, incontinent and requiring constant nursing care. The adverse economic consequences of AMD include an annual $2.6 billion negative impact on Canada's gross domestic product. The return on investment is high for both current AMD therapies and research into new treatment modalities.

Reasons for delay of surgical intervention in adult strabismus.

BACKGROUND: It has been our impression that adult patients with strabismus frequently delay surgical intervention. OBJECTIVES: To determine the length of time adult patients waited before undergoing strabismus surgery and to determine the reasons why these delays occurred. DESIGN, SETTING, AND PARTICIPANTS: Prospective survey of consecutive patients who delayed strabismus surgery for more than 1 year. INTERVENTION: Preoperative survey. MAIN OUTCOME MEASURES: The primary outcome measure was time between the onset of strabismus and surgery and the reason why surgery had not been previously sought. RESULTS: The mean age among 128 study participants was 45.7 years (age range, 18-86 years). The mean time between the onset of current strabismus and surgery was 19.9 years (range, 1-72 years). The major reasons for delay in seeking surgical treatment included the following: surgery was never offered by eye care specialist (35 patients [27%]), surgery was offered but declined by the patient (29 patients [23%]), the patient had received prior satisfactory nonsurgical care (17 patients [13%]), the patient had never sought care (14 patients [11%]), the patient had a previous poor surgical experience (8 patients [6%]), and the patient had been told by their eye specialist that nothing could be done or that surgery could make them worse (8 patients [6%]). CONCLUSIONS: Strabismus surgery is often delayed for many years in adult patients who could potentially benefit from it. Almost half of such delays could be avoided by better education of the lay public and the medical community.

The management of strabismus in adults--II. Patient and provider perspectives on the severity of adult strabismus and on outcome contributors.

PURPOSE: As part of a larger study intended to evaluate the management of strabismus in adults, we documented and compared patient and provider perspectives on the various factors that may contribute to treatment outcome and value of strabismus care. METHODS: By completing a questionnaire, 170 patients with strabismus (ages 19 to 87 years) and 11 strabismus specialists who performed surgery on these patients each indicated the relative weight of several disease- and treatment-related contributors to the outcome and value of care. In addition, each respondent rated the severity of the strabismus before and after surgery. RESULTS: Overall severity ratings improved as a result of surgery. The improvement perceived by the physicians was 5.1 +/- 1.7 on a 10-point scale and was larger than the 2.6 +/- 3.6 points improvement perceived by the patients ( P < 0.001). Patients and physicians expressed different views on the relative contributions to outcome and value (overall P < 0.001). Both groups indicated "the condition," "the physician," and "the procedures" as the largest contributors, but "condition" was perceived as more important by the physicians than by the patients ( P < 0.001), and "physician" was more important to the patients than to the physicians ( P < 0.001). CONCLUSION: Although in approximate agreement on the main contributors to outcome and value, discrepancies exist between perspectives of patients and physicians on the relative weights of those contributors. Public information, education, and counseling may bring these perspectives better in line and ultimately improve both quality and patient satisfaction.

The utility of strabismus in adults.

PURPOSE: To determine the utility (quality-of-life weight) associated with adult strabismus. METHODS: Time tradeoff utility values were measured in physician-conducted interviews with 140 adult patients with strabismus in a private practice setting. Patients also completed a questionnaire containing six items that rated the following aspects of disability: specific health problems, problems with tasks of daily living, problems with social interaction, self-image problems, concerns about the future, and job-related problems. Patients were characterized as presurgical or nonsurgical, and their diplopia and asthenopia were rated by the physician on a four-level scale. RESULTS: About 60% of all patients indicated willingness to trade part of their life expectancy in return for being rid of strabismus and its associated effects. The median utility was 0.93 (interquartile range, 0.83 to 1.0). A significantly smaller proportion (44%) of the nonsurgical patients (N = 41) appeared willing to trade time compared with surgical patients (68%; P = .009). Median utility in the presurgical patients was 0.90. Strong relationships were found between utility and the level of diplopia (P < .0001), and between utility and the level of asthenopia (P < .0001). Utility was correlated with all six disability ratings (all P < or = .00062). CONCLUSION: A majority of the patients interviewed would trade a portion of their life expectancy in return for being rid of strabismus and its associated effects. These results were validated by significant associations with diplopia, asthenopia, and disability.

The burden of age-related macular degeneration: a value-based medicine analysis.

PURPOSE: To assess the quality-of-life loss and the macroeconomic financial consequences associated with age-related macular degeneration (ARMD). METHODS: Time tradeoff utility analysis was performed to assess the quality-of-life diminution caused by ARMD (both dry and neovascular) in cohorts consisting of (1) patients with ARMD, (2) ophthalmologists asked to assume they had various degrees of severity of ARMD, (3) healthcare providers asked to assume they had various degrees of severity of ARMD, and (4) participants from the general community asked to assume they had various degrees of severity of ARMD. ARMD was classified according to vision in the better-seeing eye as (1) mild: 20/20 to 20/40, (2) moderate: 20/50 to 20/100, (3) severe: < or = 20/200, or (4) very severe: < or = 20/800. RESULTS: Mild ARMD caused a 17% decrement in the quality of life of the average patient, similar to that encountered with moderate cardiac angina or symptomatic human immunodeficiency virus syndrome. Moderate ARMD caused a 32% decrease in the average patient's quality of life, similar to that associated with severe cardiac angina or a fractured hip. Severe ARMD caused a 53% decrease in quality, more than that of dialysis, and very severe ARMD caused a 60% decrease in the average ARMD patient's quality of life, similar to that encountered with end-stage prostate cancer or a catastrophic stroke that leaves a person bedridden, incontinent, and requiring constant nursing care. Patients with varying degrees of severity of ARMD were found to have quality-of-life impairment ranging from 96% to 750% greater than that estimated by treating ophthalmologists for the same condition. An economic analysis based upon losses to the gross domestic product suggests that ARMD has approximately a $30 billion annual negative impact. The return on investment is therefore potentially high for both treatment with current ARMD therapies and the research costs invested in the development of new ARMD treatment modalities. CONCLUSIONS: ARMD is a major public health problem that has a devastating effect upon patients and marked adverse financial consequences for the economy.