We asked consecutive patients hospitalised in the intensive care unit of two large primary care Parisian hospitals for deliberate self-poisoning with drugs to write a story or a short letter relating a childhood memory not linked to the parasuicide. This request was made on the day of discharge from the hospital to patients free of any prescribed drug who were alert and who had undergone a normal neurological clinical examination. The patients were given sheets of white paper and various writing tools (pen, ball-point pen and pencil). The letter had to be signed. The control group consisted of healthy volunteers with no history of parasuicide and no depression evaluated by a MADRS (range 0-60) below 16. Patients and controls received written information about the study and gave written informed consent. A randomised number was given to each letter by an investigator (CB) not participating in the graphological evaluation. The letters from the patients and controls were then mixed. Information concerning age, sex and left or right hand status was given with the letters to two independent teams of evaluators blind to the diagnosis: (i) two graphologists and (ii) two physicians from an internal medicine unit without any knowledge about graphology. The four evaluators did not know any of the patients or the control subjects. Each evaluator decided to dichotomously classify each letter as suicide or control. In the event of a discordance between the two graphologists or between the two internists, an attempt to reach a consensual diagnosis was made by means of an open discussion.
We calculated that a sample size of 80 (40 per group) was necessary to observe a difference of 20% between the graphologists and chance (correct diagnosis by chance 50%, correct diagnosis by graphologists 70%) with β = 20%, α = 5%. Intention-to-treat analysis included the 80 letters. Per-protocol analysis was made after the exclusion, by an investigator blind to the diagnosis (JFB), of the letter expressing sadness which would have orientated the final diagnosis. The χ2 one-sample test was used to compare the observed results with a chance response of 50%.
Int J Clin Pract. 2007;61(3):411-415. © 2007 Blackwell Publishing
Cite this: Graphology for the Diagnosis of Suicide Attempts: a Blind Proof of Principle Controlled Study - Medscape - Mar 01, 2007.