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Apply the Evidence

If you believe the information you’ve found and evaluated, you’re ready to apply it. In consultation with your healthcare provider, you can weigh your options and make a decision about what to do. This section discusses the major factors to consider and offers resources to help you structure your decision making.

Making Decisions

There are three key factors to consider when you weigh your decision:

Your options,
The key outcomes for each option, and
Your preferences for each outcome.

1) Your Options

Before you make your choice, step back to ensure you have considered all the options with your healthcare provider, including the option of not doing anything. Once you are clear about all the options that are medically available, you may narrow your list by considering which are available to you (for example, through your health plan), and then narrow the list further by eliminating those you are not interested in to begin with.

2) Key Outcomes

Once you’ve narrowed the list of options, pick your top two or three options. If you are considering not taking any therapy you will want to discuss with your provider what you can expect from the natural history of the disease without any treatment.

Next, in choosing between various treatment options, consider the key outcomes that will help you decide whether one intervention is likely to be a step better than another. The mnemonic discussed earlier, STEPC, helps to consider the outcomes of:

Safety: These are serious and usually infrequent complications like death, seizures or liver failure;
Tolerability: These are usually more common nuisance side effects like nausea or dry mouth;
Efficacy: as discussed above;
Price: Your out-of-pocket costs. Your health plan will also consider whether the drug is cost-effective;
Convenience: Frequency of daily use? Is it oral, topical or injected, easy to use, etc? These factors affect whether you are likely to take the therapy as prescribed.

Explore each of these outcomes with your healthcare provider for each of the major options you are considering. It might be helpful to make some notes as you do this by creating a STEPC table.

As discussed in Evaluating Research: What are the Important Findings recording the absolute differences for efficacy, safety, tolerability and price outcomes will give you the clearest picture of the pluses and minuses between your options. Ideally when comparing between the options on safety, tolerability or efficacy, the data should come out of a single study to avoid cross-study comparisons where differences in outcomes could be attributed to differences in disease severity between the different populations studied.

In addition, as you consider and discuss the magnitude of efficacy and harm reported in research with your healthcare provider, it is important to reflect on whether the population studied relates to you. You may need to make some adjustments to extrapolate the findings to your specific situation. For example, interventions generally have greater impact in sicker populations. So, if the participants in the study are twice as ill as you are, you might expect to experience half the efficacy benefit than the study reported. On the other hand, if your disease is more severe than that of the population studied, you may expect proportionately greater benefit than that found.

Once you feel clear about the outcomes expected for each option, you can begin to weigh your choices by incorporating your preferences.

3) Your Preferences

As you go over your list of STEPC outcomes, consider your preferences for each outcome. For many, the dominant outcomes driving decisions are those of safety and efficacy. You may find it helpful to start weighing these outcomes first, before moving on to consider issues of tolerability, price and convenience.

There are a number of ways individuals rate their preferences. Some guides have you score each preference with one to five stars according to the level of importance you attach to each outcome. Another option would be to use a scale, such as from -5 to +5, where -5 would represent your strongest aversion, 0 would be neutral and +5 would signify your maximum preference for an outcome.

As you rate your preferences it’s important to consider the following issues:

The relative importance of each outcome to you.
For example if safety is at least twice as important as convenience, you might rate your preference proportionately to reflect this.
The magnitude of the difference in the outcome between options.
For example, while efficacy may be very important to you, if this difference between options feels trivial to you, your preference for this outcome would likely be restrained.
The timing of the outcomes.
Outcomes, in particular those of efficacy and safety, often occur at different times. For example, while surgery to remove plaque in the neck artery of someone who is having symptoms from a significant narrowing that impairs blood flow to the brain (something called transient ischemic attacks), may effectively prevent strokes at some point the future, there is also a safety concern of immediate stroke at the time of surgery. So even though the long term benefit of stroke prevention is larger than the risk of immediate stroke at surgery, many patients would rate the issue of safety relatively greater because they value their life in the short term more than that in the long term.

The information presented in this section is intended to help you frame your discussion and empower you in a process of informed shared decision making with your healthcare provider. But weighing your decision can feel challenging. As helpful as study findings can be, there is inherent uncertainty in applying study findings to your individual circumstances and preferences. Additional support from people you trust, other patients who have faced similar decisions and second opinions from healthcare providers with expertise in your area of concern can help you sort through the choices.

We’ve also listed a number of resources below that provide patient decision aids, which can be helpful in structuring and supporting your decision making process. Whatever support you use make sure you make your medical decision in full consultation with your physician.

Resources: Applying Evidence

Super Smart Health

Empowering Health and Wellbeing

Apply the Evidence

Making Decisions

1) Your Options

2) Key Outcomes

3) Your Preferences