Medicolegal certification of suicide: An investigation of expert determination criteria and construction of empirical criteria

On a very basic level those who study suicide are either explicitly or implicitly concerned with the certification of suicide deaths by coroners and medical examiners. Although many authors have questioned the accuracy of officially reported rates, these statistics continue to be quoted as fact, a potentially problematic practice for researchers who seek accurate and true causative factors for suicidal behavior. The virtual absence of any determination criteria for suicide has been cited as a possible key source of error and variability in officially reported suicide statistics. To address this concern, an exploratory case study experiment was conducted to test the potential impact of expert suicide determination criteria on medical examiners' and lay-coroners' medicolegal certifications of death. The study showed that expert criteria had no impact on manner of death determination or certainty of certification. This result may have stemmed from inadequacies in the criteria, the high expertise of the sampled officials, or methodological problems in the study (e.g., resulting in respondent failure to use the criteria). The first of these interpretations was addressed in the second part of this project by a survey investigation which evaluated the 22 expert-derived suicide determination criteria and 33 additional items obtained from the literature. A checklist of these items was used to collect data on a sample of 126 recent suicides and accidents investigated by 70 medical examiners. The data were divided into two separate (normative and concurrent) sets for analyses, Initial analysis of the normative data empirically confirmed that medical examiners define suicide as a self-inflicted death in which there is intent to die. Therefore, these data were used to construct an instrument to predict self-infliction and intention. This instrument proved to be a 16 item subset of the original 55 items. When validated against the concurrent data, its reliability was.869 for self-infliction scoring and.876 for intention scoring. Validity was.898 for self-infliction scoring and.843 for intention scoring. This instrument predicted 100% of suicides and 83% of accidents in the concurrent sample, thus correctly identifying 93% of all cases.