Sumeet Dua and Mohit Jain
3.1. Evidenceand Value-Based Medicine
The two most prevalent forms of clinical diagnostics are evidenceand value-based medicine (VBM).1 Evidence-based medicine (EBM) is a medical application in which individual expertise, such as experience, education, and skills, are integrated with the reliable, unambiguous, and thoughtful use of the most current, best evidence for making decisions about the care of the patient. EBM is usually initiated by a patient who questions the therapy, diagnostic tests, or prognosis provided by a physician.1 The patient brings his or her own concerns and expectations to the clinician, providing the clinician with the best possible evidence for proper healthcare. Such evidence will not help the clinician make a decision, but will aid the clinician in deciding which treatment is best.
EBM is a learning process in which clinicians use clinically relevant or pertinent information about patient treatment, diagnosis, therapy, or other healthcare problems.1 Instead of reading papers, clinicians see the evidence with respect to the individual patient problems, develop questions, and search a database that helps them get pertinent information to benefit the patient. Because interactive care includes the active participation of the patient, this system increases optimal clinician outcomes.
3.1.1. EBM Process
The EBM process consists of six steps, as listed below.
Step 1: A patient goes to the clinician for the treatment. Step 2: A clinical question arises from the patient treatment.
Step 3: The clinician selects the most reliable and unambiguous evidence, and uses it to make decisions about patient care.
Step 4: The clinician evaluates this evidence.
Step 5: The clinician returns to the patient and integrates the current evidence with some form of expertise, such as experience, education, and/or skills, for treatment.
Step 6: The clinician evaluates the treatment with the patient.
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3.1.2. Evidence-Based Medical Issues
Occasionally, problems arise from the use of EBM. The three most common of these problems are listed below.
1.Using EBM, clinicians and computational systems apply results obtained from large groups of people to individual cases, which may have different circumstances or unique characteristics that are not reflected in existing EBM records.
2.Since there is no optimal or standard way to search, it is often difficult to search EBM evidence effectively.
3.EBM does not measure or include quality of life.
3.1.3. Value-Based Evidence
VBM circumvents many of these problems.1 VBM assembles the best EBM from clinical trials, and then converts the data to value-based evidence. To create a database of VBM, a clinician must conduct a cost utility analysis. A cost utility analysis measures the health and quality of life of a patient with values ranging from 0 to 1, where 0 is death and 1 is perfect health.1 These values are also referred to as preferences. For example, if vision decreases, then the value of the utility analysis also decreases. VBM is composed of three essential components, as listed below:
1.collection of evidence-based data,
2.conversion of EBM to VBM, and
3.integration of associated costs with the value.
VBM provides a more accurate measure of patient healthcare than EBM. For example, evidence-based data from a clinical trial for diabetes might show a result, such as the improvement of the average life expectancy from eight to nine months, while the value-based data also shows this increased life expectancy, but also shows severe vomiting or pain during this time that decreases the patient’s overall quality of health.
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Sumeet Dua and Mohit Jain
3.2.Economic Evaluation of the Prevention and Treatment of Vision-Related Diseases
Over the last three decades, many countries (such as Australia, Canada, and Germany) shifted large portions of their GDP toward healthcare.2 This shift indicates an awareness of the economic importance of the maintenance of health among a nation’s residents. The economic importance of the maintenance of health can be determined through economic evaluation.
3.2.1. Economic Evaluation
An economic evaluation of healthcare can be accomplished by comparing the cost of healthcare programs, such as medical therapy, health education, diagnostic tests, etc. with the advantage or profit that such programs can provide the physicians, patients, and healthcare providers. Economic evaluation is composed of three essential components, as listed below:
1.cost minimization,
2.cost benefit, and
3.cost effectiveness.
Each of these components should be tested to determine whether a healthcare program is economically sound. Economically successful programs should cost only a minimal amount, should save money in lost productivity, and should provide good results. The most common form of economic evaluation in healthcare is cost-effectiveness analysis (CEA).2 The decision analysis method described below is used to perform CEA.
3.2.2. Decision Analysis Method
Decision analysis is a method of solving complex clinical problems in an easy and transparent manner, identifying all potential solutions, weighing all possible solutions, and selecting the optimal course of action. The decision analysis method consists of four elements: a decision tree, probabilities, costs, and benefits. A decision tree is a graphical representation that aids clinicians in making a decision based on the history of a patient’s disease, the success of care as it was delivered in the past, and the success of care
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as it was delivered to patients with similar problems. Probability is the risk of an event occurring. Probability must be calculated from the strongest evidence available. An example of probability is the likelihood of curing cataracts versus the likelihood of preventing the condition from worsening. For example, if there is 50% probability of having a cataract, then the remaining 50% probability is of not having a cataract. Costs are the monetary values, which include the care or treatment provided to the patient and the costs of traveling to a particular medical center, including time off from work. Benefits are the outcomes that measure clinical trials, vision, life expectancy, quality-adjusted life year (QALY), and other improvements to the health of the patient.
3.2.3. Advantages of Decision Analysis
There are three advantages to decision analysis: structure, evidence, and evaluation. The structure of the decision tree model allows the clinician to make an informed decision based on the history of the disease and to evaluate the effect of treatment based on other information in the model.3 Decision analysis helps to integrate evidence from a variety of data sources by introducing heterogeneity. Decision analysis can aid a clinician or other healthcare professional in translating the available evidence into estimates of cost and benefits. However, because each clinician may have had different experiences, the final decision will be affected by his or her goals and perspective.
3.2.4. Perspective in Decision Analysis
The perspective of the decision maker must be considered when applying decision analysis. The perspective may be different for a physician, an insurance representative, or a patient. Because each of these individuals may have different goals, an analytical report should clearly state who provided the opinion. For example, if the perspective originates from an insurance company, then it is likely that the costs incurred by the patient and physician are not included. In addition to considering the decision maker’s perspective, a decision tree can help the clinician decide on the best course of action for a particular patient.
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