Project Overview +

Obesity is increasingly considered among the most important public health problems of our times. Bariatric surgery is arguably the only treatment that has proven effective in producing long-term weight loss for patients with morbid obesity. Bariatric surgery also results in resolution of obesity related co-morbid conditions, improvements in quality of life, and increased survival.

There are currently four different bariatric surgical procedures in use: adjustable gastric banding, gastric bypass, sleeve gastrectomy, and duodenal switch. Bariatric surgery is considered a highly preference sensitive medical issue. Existing decision aids in bariatric surgery are limited in that they provide information about the average comparative risks and benefits of the treatment options, but do not provide customized estimates of the risks and benefits of the different procedures for individual patients. As a result of these draw-backs, decision aids are not frequently used in making treatment decisions in bariatric surgery.

Our proposal is highly innovative in that our decision support tool integrates data from a large clinical registry with individual patient data to provide patients with real-time, customized, accurate information regarding the risks and benefits of the treatment options to better inform decision making. This tool will be continuously updated to ensure that the data on risks and benefits that it provides are accurate and current. Our tool also provides information about other attributes of the treatment options that bariatric surgery patients and other relevant stakeholders feel are important for patients to consider in deciding whether and what type of bariatric surgery to have.

The proposed research promotes shared medical decision making for patients who are considering bariatric surgery for the treatment of morbid obesity. If our intervention proves effective, it will result in improved decision quality and outcomes of care for patients. It may also result in improved efficiency of care to the extent that it serves to augment or guide communication between the patient and physician to promote shared medical decision-making.

Aims +

The goals of this research proposal are to develop, implement, and evaluate an informed decision support tool for treatment of morbid obesity. This decision support tool provides patients with customized estimates of the risks and benefits of different treatment options and also information about other attributes of the options that affect decision-making.

Our specific aims are:

  1. To develop a web-based interactive decision support tool that incorporates tailored information regarding risks and benefits of the treatment options (from regression-based prediction models derived on the 35,000 patients already in the Michigan Bariatric Surgery Collaborative registry) with information regarding other salient attributes of the treatment options (derived from semi-structured interviews with stakeholders including bariatric surgery patients, bariatric program staff, and surgeons).
  2. To perform a quasi-experimental study comparing the decision support tool with usual care to determine its effects on patient decisions (treatment choice, knowledge, treatment-preference concordance, and decisional conflict) and on patient outcomes including patient satisfaction and improvements in quality of life after surgery.

Participants +

We will pilot test the tool among patients recruited from the University of Michigan bariatric program.

Intervention +

Our intervention consists of an interactive, web-based decision support tool that provides patients and their physicians with a report of customized estimates of the risks and benefits of the treatment alternatives. Development of our intervention includes both qualitative and quantitative work.

  • Use of risk and benefit models: Risk and benefit models, based on data gathered from 35,000 bariatric surgery patients already in the Michigan Bariatric Surgery Collaborative registry, is being used to develop an interactive, web-based risk/benefit calculator. After inputting data, the risk benefit calculator produces a table of predicted risks and benefits of each type of bariatric procedure. In its current form, the risk benefit calculator is meant for the use of clinicians rather than directly by patients. Part of this project will be to adapt this instrument for use by patients themselves.
  • Use of qualitative data: While our decision tool includes information required to provide tailored estimates of the risks and benefits of the treatment options, it currently lacks other information that physicians and bariatric surgery patients feel is important to decision-making. We use a multi-method qualitative approach, including focus groups and individual semi-structured interviews with bariatric surgeons and other clinical staff and post-bariatric surgery patients to ensure that a broad range of information is obtained.
  • Develop a conjoint analysis survey tool for measuring patient preferences for the risks, benefits, and other attributes of the treatment options.
Our decision tool consists of an interactive website into which patients or clinical staff input a limited number of characteristics and which then produces a report comparing the treatment options with regard to customized risk-benefit information for individual patients as well as a list of other important attributes of the treatments as identified in our qualitative work. This report is then used to guide patient/surgeon discussion of the treatment options. 

Output from this tool will also be informed by specific choices tailored to user selection, including additional information about specific comorbidities, as well as those procedures chosen for comparison.

We pilot test the tool among patients recruited from the University of Michigan bariatric program. Participants have the option of using the tool from home or other location where they have access to a computer with internet access or from the clinic using a computer station at the clinic site. We then assess the logistics of deploying the tool as well as the tool's understandability by surveying patients and interviewing bariatric surgeons after they have used it in their clinical practice to discuss the risks and benefits of the different treatment options with their patients.

Improving Patient Decisions about Bariatric Surgery

09/01/2013 - 08/31/2016


Patient-Centered Outcomes Research Institute

Principal Investigators:

Nancy J. Birkmeyer, PhD
Amir A. Ghaferi, MD, MS


Mousumi Banerjee, PhD
Angela Fagerlin, PhD
Sarah T. Hawley, PhD, MPH
Edward C. Norton, PhD
LIsa Prosser, PhD, MS