Background: Although diagnostic errors are common in hospitals, little is known about the resulting economic burden. Whether the increasing attention to patient safety has led to a decrease in diagnostic error-related claims and cost over time is also unknown. Using a publicly available dataset, we examined incidence costs and outcomes associated with diagnostic errors in inpatient settings. 

Methods: Using the National Practitioner Data Bank (NPDB), we examined the incidence and costs of paid malpractice claims (from 1 January 2004 to 30 December 2015) for diagnostic errors in the inpatient setting. The NPDB is a publicly available dataset that consists of claims paid on behalf of physicians; claims resolved solely on behalf of an institution are not included. Claims related to diagnostic errors (i.e., delay or failure to diagnose) were identified using malpractice allegation groups within the NPDB. Patient- and provider-level characteristics were tabulated using descriptive statistics. Differences between claims alleging diagnostic error vs. other categories (e.g., surgical, anesthesia, medication, blood products, obstetrics, treatment, monitoring, equipment, behavioral) were assessed using Wilcoxon rank-sum, chi-square tests, and logistic regression. Trends for incidence of diagnostic error-related allegations and median annual payment were assessed using the Cochran-Armitage and nonparametric trend test. Results were expressed as percentages, medians, and odds ratios (OR) with corresponding 95% confidence intervals (CI).

Results:  A total of 41,691 claims of malpractice in the inpatient setting were evaluated. Of these, 8,294 (19.9%) were related to diagnostic error —the second most frequent type of claim behind surgical error (34.5%). Specific patient and provider-variables were also associated with inpatient diagnostic error (Table 1). Compared to other categories, claims related to inpatient diagnostic errors were associated with greater rates of disability and death (OR=2.51 [95%CI=2.35-2.69] and 2.88 [95%CI=2.70-3.07], respectively; p<0.001 for both). The proportion of paid malpractice claims attributable to diagnostic error declined from 19.7% in 2011 (n=582) to 14.8% in 2015 (n=4) (p<0.001). However, median payments for diagnostic error-related claims increased from $72,500 in 2004 to $245,000 in 2013 (p=0.02) (Figure 1).Diagnostic error-related payments accounted for $3.15 billion of the $14.83 billion (21.2%) paid out over the study period.


Although claims paid for diagnostic error appear to be decreasing in number, they are often associated with disability and death. As costs associated with these errors remains substantial, dedicated strategies to combat diagnostic errors in the hospital are necessary.