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An R-Based Landscape Validation of a Competing Risk Model
Published on: September 16, 2022
Validation of the What Matters Index: A brief, patient-reported index that guides care for chronic conditions and can
John H Wasson1, Lynn Ho2, Laura Soloway3
1Centers for Health and Aging, Dartmouth Medical School, Lebanon, NH, United States of America.
Introduction:
Current health care delivery relies on complex, computer-generated risk models constructed from insurance claims and medical record data. However, these models produce inaccurate predictions of risk levels for individual patients, do not explicitly guide care, and undermine health management investments in many patients at lesser risk. Therefore, this study prospectively validates a concise patient-reported risk assessment that addresses these inadequacies of computer-generated risk models.
Methods:
Five measures with well-documented impacts on the use of health services are summed to create a "What Matters Index." These measures are: 1) insufficient confidence to self-manage health problems, 2) pain, 3) bothersome emotions, 4) polypharmacy, and 5) adverse medication effects. We compare the sensitivity and predictive values of this index with two representative risk models in a population of 8619 Medicaid recipients.
Results:
The patient-reported "What Matters Index" and the conventional risk models are found to exhibit similar sensitivities and predictive values for subsequent hospital or emergency room use. The "What Matters Index" is also reliable: akin to its performance during development, for patients with index scores of 1, 2, and ≥3, the odds ratios (with 95% confidence intervals) for subsequent hospitalization within 1 year, relative to patients with a score of 0, are 1.3 (1.1-1.6), 2.0 (1.6-2.4), and 3.4 (2.9-4.0), respectively; for emergency room use, the corresponding odds ratios are 1.3 (1.1-1.4), 1.9 (1.6-2.1), and 2.9 (2.6-3.3). Similar findings were replicated among smaller populations of 1061 mostly older patients from nine private practices and 4428 Medicaid patients without chronic conditions.
Summary:
In contrast to complex computer-generated risk models, the brief patient-reported "What Matters Index" immediately and unambiguously identifies fundamental, remediable needs for each patient and more sensibly directs the delivery of services to patient categories based on their risk for subsequent costly care.
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