1. Differences in prevalence of ICD-10 and ICD-11 personality disorders in psychiatric settings
Professor Peter Tyrer (Imperial College, London)
(with the help of many colleagues)

2. Declaration of interest – I am Chair of ICD-11 work group for revision of classification of personality disorders
These are the others who helped:
Professor Mike Crawford, Drs Rahil Sanatinia, Helen Tyrer, Ms Sylvia Cooper, Centre for Mental Health, Imperial College, London W6 8RP 
Drs Chris Muller-Pollard, Polyxeni Christodoulou, Hammersmith and Fulham Mental Unit, London SW6
Drs Maria Zauter-Tutt, Katerina Miloseska-Reid, Ms Gemma Loebenberg, Central North West London NHS Mental Health Foundation Trust
Dr Boliang Guo, University of Nottingham
Professor Min Yang, School of Public Health, Sichuan University, Chengdu, China
Professor Duolao Wang, University of Liverpool
Professor Scott Weich, University of Warwick

3. Aims
To give you some boring definitions of levels of disorder in ICD-10 and ICD-11
To remind you never to use words like ‘borderline’, ‘narcissistic’, ‘paranoid’ and ‘schizotypal’ ever again when talking about personality disorder, unless of course you are referring to colleagues
To describe the prevalence of ICD-10 and ICD-11 personality disorder in populations in (i) medical out-patients, (ii) general practice psychiatric clinics (iii) an acute in-patient ward
To explain the results

4. Lancet 2015, 385,

5. ICD-10 general definition
These types of condition comprise deeply ingrained and enduring behaviour patterns, manifesting themselves as inflexible responses to a broad range of personal and social situations. They represent either extreme or significant deviations from the way the average individual in a given culture perceives, thinks, feels, and particularly relates to others. Such behaviour patterns tend to be stable and to encompass multiple domains of behaviour and psychological functioning. They are frequently, but not always, associated with various degrees of subjective distress and problems in social functioning and performance. .

6. ICD-11 general definition
Personality disorders are characterized by a pervasive disturbance in the individual’s way of interpreting and thinking about himself or herself, others and the world that is manifested in both emotional experience and expression and in patterns of behaviour. The disturbance is associated with significant problems in functioning that are particularly evident in interpersonal relationships and these are manifest across a range of personal and social situations (i.e.not limited to specific relationships or situations). The disturbance is of long duration (2 years or more). Most commonly personality disorders have their first manifestations in childhood and are fully evident in adolescence.

7. Level 1 of ICD-11 – personality difficulty
A long-standing, recurrent or intermittent disturbance in an individual’s way of viewing the self, others and the world, that is manifest in both emotional experience and expression, and in patterns of behavior. The disturbance is associated with some problems of social functioning and interpersonal relationships. However, impairment in functioning is not as severe as that found among people with personality disorder and are seen only in certain social and interpersonal contexts than may not be apparent elsewhere.

8. Level 2 of ICD-11 – mild personality disorder

9. Level 3 of ICD-11 – moderate personality disorder

10. Level 4 of ICD-11 – severe personality disorder

11. More on severe pd

12. Domains are qualifiers, not diagnoses

13. Prevalence in people with health anxiety attending medical clinics
Total 442
ICD-10 -no personality disorder
289 (65.4)
ICD-11 – no personality disorder
258 (58.4)
ICD-10 – personality disorder
153 (34.6)
ICD-11 – personality disorder
184 (44.6)
ICD-10 – mixed diagnoses
66 (14.9)
ICD-11 – no personality dysfunction
62 (14)
ICD-11 – personality difficulty
196 (44.3)
ICD-11 – mild personality disorder
142 (32.1)
ICD-11 – moderate personality disorder
40 (9)
ICD-11 – severe personality disorder
2 (0.5)

14. Prevalence in people in general practice psychiatric clinics
Total 198
ICD-10 -no personality disorder
138 (69.3)
ICD-11 – no personality disorder
132 (66.7)
ICD-10 – personality disorder
60 (30.3)
ICD-11 – personality disorder
66 (33.3)
ICD-10 – mixed diagnoses
25 (12.6)
ICD-11 – no personality dysfunction
91 (45.7)
ICD-11 – personality difficulty
40 (20.1)
ICD-11 – mild personality disorder
43 (21.6)
ICD-11 – moderate personality disorder
17 (8.5)
ICD-11 – severe personality disorder
6 (3)

15. Prevalence in people in an acute in-patient ward
Total 82
ICD-10 -no personality disorder
51 (62)
ICD-11 – no personality disorder
40 (48.8)
ICD-10 – personality disorder
31 (38)
ICD-11 – personality disorder
42 (51.2)
ICD-10 – mixed diagnoses
7 (9)
ICD-11 – no personality dysfunction
28 (34.1)
ICD-11 – personality difficulty
12 (14.6)
ICD-11 – mild personality disorder
19 ((23.2)
ICD-11 – moderate personality disorder
10 (12.2)
ICD-11 – severe personality disorder
13 (15.9)

16. Main reason for higher prevalence of ICD-11 in all settings

17. Main message
Go forth into the personality undergrowth, cleave the old battered bushes and clear the air.
A bold future awaits both patients and practitioners in the sensible new world of classification