The Effect of Total Cost Information on Consumer Treatment Decisions: An Experimental Survey

Testing for a Sweet Spot in Randomized Trials

Introduction

Randomized trials recruit diverse patients, including some individuals who may be unresponsive to the treatment. Here we follow up on prior conceptual advances and introduce a specific method that does not rely on stratification analysis and that tests whether patients in the intermediate range of disease severity experience more relative benefit than patients at the extremes of disease severity (sweet spot).

Methods

We contrast linear models to sigmoidal models when describing associations between disease severity and accumulating treatment benefit. The Gompertz curve is highlighted as a specific sigmoidal curve along with the Akaike information criterion (AIC) as a measure of goodness of fit. This approach is then applied to a matched analysis of a published landmark randomized trial evaluating whether implantable defibrillators reduce overall mortality in cardiac patients (n = 2,521).

Results

The linear model suggested a significant survival advantage across the spectrum of increasing disease severity (β = 0.0847, P < 0.001, AIC = 2,491). Similarly, the sigmoidal model suggested a significant survival advantage across the spectrum of disease severity (α = 93, β = 4.939, γ = 0.00316, P < 0.001 for all, AIC = 1,660). The discrepancy between the 2 models indicated worse goodness of fit with a linear model compared to a sigmoidal model (AIC: 2,491 v. 1,660, P < 0.001), thereby suggesting a sweet spot in the midrange of disease severity. Model cross-validation using computational statistics also confirmed the superior goodness of fit of the sigmoidal curve with a concentration of survival benefits for patients in the midrange of disease severity.

Conclusion

Systematic methods are available beyond simple stratification for identifying a sweet spot according to disease severity. The approach can assess whether some patients experience more relative benefit than other patients in a randomized trial.

Does Societal Cost Information Affect Patient Decision-Making in Carpal Tunnel Syndrome? A Randomized Controlled Trial

Background: Despite studies demonstrating the effects of out-of-pocket costs on decision-making, the effect of societal cost information on patient decision-making is unknown. Given the considerable societal impact of cost of care for carpal tunnel syndrome (CTS), providing societal cost data to patients with CTS could affect decision-making and provide a strategy for reducing national health care costs. Therefore, we assessed the following hypotheses: (1) there is no difference in treatment choice (surgery vs no surgery) in a hypothetical case of mild CTS between patients randomized to receive societal cost information compared with those who did not receive this information; (2) there are no factors (eg, sex, experience with a previous diagnosis of CTS, or receiving societal cost information) independently associated with the choice for surgery; and (3) there is no difference in attitudes toward health care costs between patients choosing surgery and those who did not. Methods: In this randomized controlled trial using a hypothetical scenario, we prospectively enrolled 184 new and return patients with a nontraumatic upper extremity diagnosis. We recorded patient demographics, treatment choice in the hypothetical case of mild CTS, and their attitudes toward health care costs. Results: Treatment choice was not affected by receiving societal cost information. None of the demographic or illness factors assessed were independently associated with the choice for surgery. Patients declining surgery felt more strongly that doctors should consider their out-of-pocket costs when making recommendations. Conclusions: Providing societal cost information does not seem to affect decision-making and may not reduce the overall health care costs. For patients with CTS, health policy could nudge toward better resource utilization and finding the best care pathways for nonoperative and invasive treatments.

The Influence of Cost Information on Treatment Choice: A Mixed-Methods Study

PURPOSE

To test the null hypothesis that exposure to societal cost information does not affect choice of treatment for carpal tunnel syndrome (CTS).

METHODS

We enrolled 304 participants using the Amazon Mechanical Turk platform to complete a survey in which participants were given the choice between carpal tunnel release (CTR) or a less-expensive option (orthosis wear) in a hypothetical mild CTS scenario. Patients were randomized to receive information about the societal cost of CTR (cost cohort) or no cost information (control). The primary outcome was the probability of choosing CTR measured on a 6-point ordinal scale. We employed qualitative content analysis to evaluate participants' rationale for their choice. We also explored agreement with various attitudes toward health care costs on an ordinal scale.

RESULTS

Participants in the cost cohort exhibited a greater probability of choosing surgery than those in the control cohort. The relative risk of choosing surgery after exposure to societal cost information was 1.43 (95% confidence interval, 1.11-1.85). Among participants who had not previously been diagnosed with CTS (n = 232), the relative risk of choosing surgery after exposure to societal cost information was 1.55 (95% confidence interval, 1.17-2.06). Lack of personal monetary responsibility frequently emerged as a theme in those in the cost cohort who chose surgery. The majority (94%) of participants expressed at least some agreement that health care cost is a major problem whereas only 58% indicated that they consider the country's health care costs when making treatment decisions.

CONCLUSIONS

Participants who received societal cost information were more likely to choose the more expensive treatment option (CTR) for mild CTS.

CLINICAL RELEVANCE

Exposure to societal cost information may influence patient decision making in elective hand surgery. A complete understanding of this influence is required prior to implementing processes toward greater cost transparency for diagnostic/treatment options. Sharing out-of-pocket costs with patients may be a beneficial approach because discussing societal cost information alone will likely not improve value of care.