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Killed by Police: Validity of Media-Based Data and Misclassification of Death Certificates in Massachusetts,
Justin M Feldman1, Sofia Gruskin1, Brent A Coull1
1Justin M. Feldman and Nancy Krieger are with the Department of Social and Behavioral Sciences, Harvard T. H. Chan School of Public Health, Boston, MA. Sofia Gruskin is with the Program on Global Health and Human Rights, Institute for Global Health, University of Southern California, Los Angeles. Brent A. Coull is with the Department of Biostatistics, Harvard T. H. Chan School of Public Health.
Objectives:
To assess the validity of demographic data reported in news media-based data sets for persons killed by police in Massachusetts (2004-2016) and to evaluate misclassification of these deaths in vital statistics mortality data.
Methods:
We identified 84 deaths resulting from police intervention in 4 news media-based data sources (WGBH News, Fatal Encounters, The Guardian, and The Washington Post) and, via record linkage, conducted matched-pair analyses with the Massachusetts mortality data.
Results:
Compared with death certificates, there was near-perfect correlation for age in all sources (Pearson r > 0.99) and perfect concordance for gender. Agreement for race/ethnicity ranged from perfect (The Counted and The Washington Post) to high (Fatal Encounters Cohen's κ = 0.92). Among the 78 decedents for whom finalized International Classification of Diseases, 10th Revision (ICD-10), codes were available, 59 (75.6%) were properly classified as "deaths due to legal intervention."
Conclusions:
In Massachusetts, the 4 media-based sources on persons killed by police provide valid demographic data. Misclassification of deaths due to legal intervention in the mortality data does, however, remain a problem. Replication of the study in other states and nationally is warranted.
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