Scientific background: Dark Tetrad (SD4)
About this test
Paulhus and Williams coined the term "Dark Triad" in 2002 for three socially unpopular but overlapping personality traits -- narcissism, Machiavellianism, and psychopathy -- which proved to be distinct but related constructs. Buckels, Jones, and Paulhus (2013) showed that everyday sadism (enjoyment of cruelty toward others) represents a fourth, empirically separable facet -- since then, researchers have spoken of the "Dark Tetrad." In 2020, Paulhus, Buckels, Trapnell, and Jones published the SD4 (Short Dark Tetrad) in the European Journal of Psychological Assessment as a compact, 28-item short form that captures all four traits with good internal consistency (Cronbach's alpha between .76 and .81), replacing the previous three-trait SD3 short scale from the same author team. Importantly: these traits are understood as normally distributed personality characteristics in the general population ("subclinical") -- they are conceptually distinct from the clinical diagnoses of Narcissistic or Antisocial Personality Disorder, or clinical psychopathy (which is assessed via, e.g., the clinician-administered PCL-R). The bands used here are based on the item means and standard deviations reported in the original study for a sample of 637 University of Winnipeg students, and serve only as a rough point of reference, not a clinical norm.
Dimensions
Machiavellianism
Strategic, goal-directed thinking: planning, discretion, and the deliberate use of manipulation to advance your own interests over time.
Narcissism
Feelings of grandiosity, a need for admiration, and the conviction of being special and destined to lead.
Psychopathy
Impulsivity, low fear of consequences, and a tendency toward rule-breaking and risky behavior.
Sadism
Enjoyment of violence, cruelty, or others' suffering -- the fourth, distinct facet of the Dark Tetrad.
Sources & license
Paulhus, D. L., Buckels, E. E., Trapnell, P. D., & Jones, D. N. (2020). Screening for dark personalities: The Short Dark Tetrad (SD4). European Journal of Psychological Assessment, 37(3), 208–222.
Delroy L. Paulhus (University of British Columbia) explicitly lists the SD4 as "In the Public Domain" on his own measures page: "The following questionnaires are available without permission. Feel free to download and use as needed." Item wording, response-scale anchors, and scoring were verified verbatim against Paulhus's own distributed SD4 instrument document.
https://www2.psych.ubc.ca/~dpaulhus/Paulhus_measures/SD4.docxBuckels, E. E., Jones, D. N., & Paulhus, D. L. (2013). Behavioral confirmation of everyday sadism. Psychological Science, 24(11), 2201–2209.
Referenced as scientific background for including sadism as the fourth Dark Tetrad facet.