The “thermostat model” of health care utilization
Danil Makarov and colleagues have an interesting paper in the April 2012 issue of Health Affairs entitled “Appropriate And Inappropriate Imaging Rates for Prostate Cancer Go Hand In Hand By Region, As If Set By Thermostat.” Using data from the SEER-Medicare database, the researchers examined regional differences in imaging for prostate cancer patients. The SEER program of the National Cancer Institute collects information about cancer site, stage, and histology for cancer patients from sixteen geographic regions. For cancer patients who are included in the SEER database and are covered by Medicare, information is available on Medicare claims for health care services. The sample consisted of 48,148 prostate cancer patients aged 66-85 who were diagnosed with prostate cancer in 2004 or 2005.
The patients were divided into low- and high-risk groups. According to the 2002 guidelines of the National Comprehensive Cancer Network, which were in effect at the time, high-risk patients should receive imaging such as bone scans, MRIs and CT scans under certain circumstances. In low-risk patients, all imaging was considered inappropriate except CT scans for planning purposes in patients undergoing external beam radiation therapy.
The researchers found that overall rates of imaging varied among the different SEER regions. Imaging appropriateness was not uniformly worse in regions with high rates of overall imaging. Rather, regions with high overall imaging rates had higher rates of inappropriate imaging and higher rates of appropriate imaging. Men with high-risk prostate cancer were more likely to receive appropriate imaging if they lived in areas with higher rates of inappropriate imaging. The authors call this the “thermostat model” of health care utilization. Dividing the regions into quartiles according to rates of inappropriate imaging of low-risk men, in quartile 4 (highest rate of inappropriate imaging), the odds ratio for men with high-risk prostate cancer receiving appropriate imaging was 1.75, with odds ratios in the next two quartiles being 1.48 and 1.04.
The authors state that their analysis suggests that
efforts to lower inappropriate use of imaging may simultaneously lower appropriate use of imaging because the two appear to be coupled. Therefore, policy measures aimed simply at limiting inappropriate imaging in regions with high resource use could have the unintended consequence of decreasing imaging for those patients for whom such care is indicated.
Policies will need to be multifaceted to break down the thermostat-like relationship between inappropriate and appropriate health care use. Accountable care organizations will need clearly defined quality metrics for a broad range of conditions. They will also need well-designed systems to ensure that the right patients are getting the right tests and procedures — and that costs are not contained at the expense of quality. Cost-control policies must selectively educate providers to change their behavior and reduce the use of unnecessary care, while still ensuring appropriate care. Such efforts could take on many forms: profiling physicians who inappropriately overuse resources, linking payment to appropriate utilization criteria, or providing rewards and incentives to physicians and organizations that optimize resource use.
Danil V. Makarov, Rani Desai, James B. Yu, Richa Sharma, Nitya Abraham, Peter C. Albertson, Harlan M. Krumholz, David F. Penson, Cary P. Gross. Appropriate And Inappropriate Imaging Rates For Prostate Cancer Go Hand In Hand By Region, As If Set By Thermostat. Health Affairs 31:4 (2012).
Addendum 4/23/2012: see also Jeff Levin-Scherz’s post on his Managing Healthcare Costs blog.
Data sharing as a moral imperative
In the USA at least, the data legally belong to trialists on the grounds that it requires work to create knowledge from data. But science, particularly medical science, is essentially an enterprise conducted for moral reasons. We need to do not just what is legal but what is right. As such, we must take into account the probable wishes of the patients who give us their blood, fill in our questionnaires and die on our trials. It is difficult to believe that any patient on my trial, who completed complex questionnaires so diligently over such a long period of time, would really have wanted me to keep the data for myself rather than share it with others for the benefit of medical science in general. Vickers AJ. Whose data set is it anyway? Sharing raw data from randomized trials. Trials. 2006;7:15.
Every day, patients and their caregivers are faced with difficult decisions about treatment. They turn to physicians and other healthcare professionals to interpret the medical evidence and assist them in making individualized decisions. Unfortunately, we are learning that what is published in the medical literature represents only a portion of the evidence that is relevant to the risks and benefits of available treatments. In a profession that seeks to rely on evidence, it is ironic that we tolerate a system that enables evidence to be outside of public view. Krumholz HM. Open Science and Data Sharing in Clinical Research: Basing Informed Decisions on the Totality of the Evidence. Circulation: Cardiovascular Quality and Outcomes. 2012;5: 141-142
We are all patients, and will all face questions about what medical treatments to pursue. Some questions are trivial and unimportant, others can mean the difference between life and death. We rely on evidence-based medicine to give us reliable information about the risks and benefits associated with medical interventions, but a disturbing amount of evidence indicates that the medical literature is not always reliable. Many clinical trials are not published within a reasonable time after completion or are never published at all. Missing data leads to systematic reviews that are based on only a portion of the trials that were conducted, which can affect the results in unknown and unpredictable ways. Missing data may in some cases hold important information about risk, as in the case of Vioxx (rofecoxib). Merck had data several years before Vioxx was withdrawn from the market that showed the drug increased the risk of heart attacks, but most of the data was unpublished and out of public view. In other cases, clinical trials are published but the data are reported in a misleading and biased way, as when a negative trial is presented so as to appear positive, or analyses showing harm are omitted.
What is to be done? What can we do to make evidence-based medicine more evidence-based? Four commentaries in the March 2012 issue of Circulation: Cardiovascular Quality and Outcomes discuss how making clinical research data available outside individual drug and device companies or research groups could greatly add to the depth and reliability of our knowledge. Currently, with certain exceptions, access to most clinical trial data is restricted to the investigators or the funders. Harlan Krumholz, in an editor’s perspective, outlines the key concepts:
Now is the time to bring data sharing and open science into the mainstream of clinical research, particularly with respect to trials that contain information about the risks and benefits of treatments in current use. This could be accomplished through the following steps:
Post, in the public domain, the study protocol for each published trial. The protocol should be comprehensive and include policies and procedures relevant to actions taken in the trial.
Develop mechanisms for those who own trial data to share their raw data and individual patient data.
Encourage industry to commit to place all its clinical research data relevant to approved products in the public domain. This action would acknowledge that the privilege of selling products is accompanied by a responsibility to share all the clinical research data relevant to the products’ benefits and harms.
Develop a culture within academics that values data sharing and open science. After a period in which the original investigators can complete their funded studies, the data should be de-identified and made available for investigators globally.
Identify, within all systematic reviews, trials that are not published, using sources such as clinicaltrials.gov and regulatory postings to determine what is missing.
It must be acknowledged that there are many obstacles — political, cultural, financial — to accomplishing these goals. Some of these obstacles are discussed in the other three commentaries, which are open access and which I urge you to read:
Spertus, JA. The Double-Edged Sword of Open Access to Research Data. Circulation: Cardiovascular Quality and Outcomes. 2012;5;143-144.
Ross JS, Lehman R, Gross CP. The Importance of Clinical Trial Data Sharing: Toward More Open Science. Circulation: Cardiovascular Quality and Outcomes. 2012;5;238-240.
Gotzsche PC. Strengthening and Opening Up Health Research by Sharing Our Raw Data. Circulation: Cardiovascular Quality and Outcomes. 2012;5;236-237.
Whatever the difficulties, the current situation is clearly intolerable. Patients deserve reliable information on the risks and benefits of medical treatments and the subjects of clinical trials deserve that their contributions be fully used to benefit other patients.
Addendum March 26, 2012: Please also see these posts by Jim Murray and Gary Schwitzer.