Death/Suicide IAT

Background

The Implicit Association Task (IAT) is a widely used measure of the strength of automatic, internal concept associations. It was pioneered by Anthony Greenwald and colleagues in 1998. First used as a measuring tool to uncover implicit social biases such as racism, not easily revealed with explicit self-report measures like questionnaires, the IAT paradigm soon found its way into other areas of human behavior such as consumer research and health related domains.

The Suicide IAT, also known as the Death IAT, developed by Matthew Nock and Mahzarin Banaji leverages the IAT paradigm to circumvent a critical flaw in traditional suicide risk management: the reliance on patients' self reports. Patients either cannot or -deliberately choose not to- reveal their suicide ideation and intent.

The basic idea of the Suicide IAT is that people with suicide intent show an increasingly stronger connection between the concepts "Self" and "Death". Thus asking people to quickly sort items of categories 'self' vs. 'others' and items of categories 'death' vs. 'life' within the IAT paradigm reveals how strongly associated the concepts 'death' and 'self' are for individual people at any given time. This information in turn helps inform patient treatment plans.

In a landmark study from 2010 conducted at Massachusetts General Hospital, Nock and colleagues could show that patients who had just attempted suicide had indeed significantly stronger automatic associations between the concepts "Self" and "Death" than other psychiatric patients who were in the ER for other reasons. In addition, the study found that patients with a strong "Self-Death" association were six times more likely to attempt suicide within the next six months, a finding that surpasses the predictive validity of known risk factors.

Task Procedure

Participants are asked to categorize self and other-related attributes (e.g. "myself"; "they") and target items (e.g. "dead" vs. "alive") into predetermined categories via keystroke presses. The basic task is to press the left key (E) if an item (e.g. "myself") belongs to the category presented on the left (e.g. "ME") and to press the right key (I) if the word (e.g. "they") belongs to the category ("Not-Me") presented on the right. The items are presented one-by-one, and participants are asked to respond as quickly as possible without making too many mistakes. If a mistake is made, error feedback is provided in the form of a red 'X' and the response has to be corrected.

For practice, participants sort items into the target categories "Life vs. Death" and attribute categories "Me vs. Not-Me", separately. For the test, participants are asked to sort categories into the paired/combined categories (e.g. "Me or Death" on the left vs. "Not-Me OR Life" on the right). Pairings are reversed for a second test (e.g. "Me OR Life" on the left vs. "Not-Me or Death" on the right). Each test block is separated into a short (20 trial) and a longer (40 trial) phase. Separate d-scores are calculated for both, and their unweighted mean is taken as the overall d-score.

What it Measures

The IAT measures the strength of subconscious links between different mental concepts

Psychological domains

• Implicit Cognition: Cognitive Processes not under conscious control
• Suicide Ideation: Thinking about, considering, or planning suicide

Main Performance Metrics

• d-score: Measure of strength between associated concepts (Self and Death)

Psychiatric Conditions

IAT measures are used, amongst others, for study with the following patient groups

• Suicide
• Depression
• Self-harm
• Eating Disorders