Brit.J.

Psychiat. (1976), ia8, 537-40

Cross-Validation of a Predictive Scale for Subsequent Suicidal Behaviour in an Italian Sample CHRISTA

By N. GARZO1TO, ROBERTA SIANI, ZIMMERMANN TANSELLA and M. TANSELLA

Summary. A six-point predictive scale for parasuicide repetition developed by Buglassand Horton (1974a)was testedon a group of patientsadmittedfor parasuicide to a psychiatric ward of one of the city hospitals of Verona. The scale gave a range of probability of repetition within 12 months of 15 per cent

at a score of o up to 45.5 per cent at the scores 3, 4, 5 and 6. Moreover the scale discriminated significantly between repeaters and non-repeaters. Items significantly associated with repetition in the Italian sample, which are not represented by the six-point scale were: previous parasuicide not admitted to hospital, violence received, alcohol taken at time of act, less than one year at the present address.

A substantial proportion of patients (2o—3o per cent) admitted for attempted suicide (parasuicide) are reportedtorepeatsuicidalbeha viour within a year (World Health Organiza tion,

ig68).

The

early

identification

of ‘¿repeaters'

sheet consistently discriminated repeaters from non-repeaters in three separate cohorts. The resulting

nine-item

list differs

from

the former

six-item scale by four additional items (social class V, dependence on drugs, unemployment, and a history of criminal behaviour) and the

therefore becomes important, especially when omission of one item (not living with relatives). resources are limited and special attention has to be concentrated on the group at the greatest The predictive value of these nine items is still risk of relapse (Buglass and McCullock, 5970; unknown. In the present study the validity of the six Buglass and Horton, 1974a). A new predictive scale has recently been item predictive scale has been tested in a group of patients admitted for parasuicide to the developed by Buglass and Horton (I9@a) and successfully validated for both sexes on two psychiatricward of a general hospital in successive cohorts. It consists of six items, Verona. Moreover, repeatersand non-repeaters allowing one point each, and gives a range of were compared on the basis of the six-item scale, probability of repetition within twelve months of the nine-item list and the 24-item data sheet used 5 per centat thescoreof0 up to48 per centat by Buglassand Horton (ig@a). Furthermore, thescores5 and 6.These items,selected from a singleitems significantly associatedwith repeti 24-items listdescribing the social situation, tionin our samplewere identified. clinical diagnosis and past history of the patient METHOD

are:diagnosisof sociopathy,problem in the use of alcohol,previous in-patienttreatment,pre

There were 120 patients admittedforpara

vious psychiatric out-patient treatment, previous parasuicide resulting in hospital admission, not living with relatives. In a laterpaper Buglassand Horton (1974b) examined which of the 24 items of the data 2

suicideto the PsychiatricUniversity Clinicof

Verona during the first three years of its activity (‘.4.'93'.3.'g@).

This Clinic is a 36-bed ward in a general hospital. The admissions are in general selective

‘¿37

138

CROSS-VALIDATIONOF A PREDICTIVESCALE FOR SUBSEQ@TJENT SUICIDALBEHAVIOUR

only in so far as to exclude patients under 14 years and presumably long-stay patients; corn pulsory admissions are not possible. Whereas the patients admitted may be considered as

The number of patients admitted for para suicide increased steadily over the three years, while the percentage of the identified repeaters

representative

remained

of the population

of psychiatric

RESULTs

fairly

constant

at about

26 per cent

patients in our district on the basis of the fre

(Table I). Women were slightly more likely to

quency graphic

repeat

of diagnostic data (Tansella

categories and of socio ci ci., 1974), this cannot

be said for our parasuicide patients, who are a highly selective group. Many parasuicide patients

are

admitted

to

other

psychiatric

facilities and some are discharged from the resuscitation departments of the two general hospitals of the city without having seen a psychiatrist. Moreover, the majority of the parasuicide patients admitted to our ward come from the lower social classes. Members of the middle and upper classes commonly call on private clinics or their general practitioners, and their number is therefore under-represented in our sample. In 5974 all 120 parasuicide patients (the 12 per

cent

during

the first three years) were invited

of the

letter for a follow-up

total

number

interview.

(27 per cent)

than

men

(23 per cent).

The distribution ofthesix-item scalescores by repetition is shown in Table II. The scale gives a range ofprobabilityofrepetition of 55 per cent at the score of 0 up to 45@5 per cent at the

scores 3, 4, 5 and 6, the predictive power of the scale being somewhat lower for our sample than forBritish subjects(Buglassand Horton, 1974a).The scaleislesseffective for the higher

[email protected] I FR@Petitio@of suicidal behaviour within 12 months

CohortsParas

—¿

Nters %*NInterviewed %Repea %70—71Nulcides

of admissions

by

Non-responding

patients living in the district were the social worker and interviewed The follow-up period covered one the patient's first discharge from the

visited by at home. year after clinic, and

information was collected about any subsequent parasuicidal act; the 24-item data sheet used by Buglass and Horton (1974a), including demo

graphic, clinical and social data referring to the patient at the time ofhis first discharge, was then completed. Information about 76 per cent (9' patients) ofthe total number of parasuicides

II 75—72 47 31 26Total120129!762426 72—7314596 54II 4979

*

Percentage

66 833

8

of total admissions.

[email protected] Sir-item scale (Buglass and Horton, 1974a) tested on the Italian sample Distribution

of scores by repetition, with percentages in

brackets

Score0 collected, the remainder having left the district or being untraceable. I 234 A x2 analysis ofthethreeannual cohortsfor 56TotalRepeaters4

was

repeatersand non-repeatersseparatelyshowed

thehomogeneityofthesamplesinrespect tothe 24 items collected. Only the item ‘¿previous out patient psychiatric treatment' increased signi

ficantly in frequency over the three years for the non-repeaters. All the patients were there fore treated as a single cohort, including both sexes. No patient

in this cohort

appears

ignored.

8 7 -@24Non(is)(23)(s7)4

I ‘¿0

—¿@ (j@.@)0

27 52 repeaters22 (85)(@fl) (63)33

-@67Total

twice.

Thirteen patientshad second admissionsin successive years;thesesecond admissionswere

26

1327

=ioo%26

35 5973

0 —¿@

(@)0 I09!

BY N. GARZOTIO,

ROBERTA

SIANI,

CHRISTA

ZIMMERMANN

TANSELLA

AND M. TANSELLA

139

TArnI III Rating scores (medians and ranges) and comparison of repeatersand non-repeatersusing three different item lists

(Mann-Whitney U test; two-tailed) 67)ZPMedianRangeMedianRange6items@@5()0—5o@860—4—2@I33•OI9itCITIS (N = = 24)Non-repeaters ItemlistsRepeaters(N

24iteiflS..

....

..2@2O

2—12I@70 4@100—5

4@50o-6

risk groups scoring 3 and more. This is due to the small size of the higher risk groups which are inevitably subject to fluctuation. Table III shows the comparison of repeaters and non-repeaters on the basis of the six-item scale

and

point

the nine

scale

longer

and

discriminates

item

24 item as

lists (p =

.oi)

lists. The

well

as

between

the

six two

the two

groups and is therefore preferable. Table IV shows that three items of the 24item list in our sample were associated with repetition

at

(diagnosis

of sociopathy,

the

02

level

of

significance

previous

parasuicide

not admitted to hospital, violence received) and two items at the ‘¿05 level of significance (alcohol taken at time of act, less than one year at the

present address).

—¿[email protected]'•¿0I 0-9—2@076

DISCUSSION

The complete lack ofany official figures about parasuicidal

acts in Italy prevents

us from draw

ing any conclusions about our sample, which is likely to be a highly selective group. Despite these limitations, together with the small sample size, and despite the different cultural context in which the Buglass-Horton scale was used, the results

are

encouraging

: 83 per

cent

of the

repeaters were correctly identified (scoring i or more), which is very near to the proportion of 88 per cent found by Buglass and Horton (1974a),

and

i 7 per

cent

were

missed.

The

proportion of the non-repeaters falsely classified as potential repeaters was 67 per cent compared to 56 per cent reported by Buglass and Horton ( I 974a). Becaus@non-repeaters outnumber re peaters, the risk group (scoring i or more) contains

more than twice as many non-repeaters

as repeaters. This degree of misclassification [email protected] IV

non-repeaters

Comparisonof repeatersand non-repeaters Items significantly associated with repetition (x' test with Tates' correction)

Non Items

Repeaters 0/ /0repeaters

/0PDiagnosis

of sociopathy

..

ofview

of

high, but from a clinical

less serious

than

a misclassification

of repeaters would be. Comparing repeaters and non-repeaters on every single item of the 24 item list, only one (diagnosis

ofsociopathy)

ofthe

five items which

were significantly associated with repetition belongs to the six-item scale. This suggests that for our sample other characteristics may be more

0/

Alcohol time215‘02of taken at act

point

is rather

..

Previous parasuicide257‘05not

important

for parasuicide

described

by the six-item

further

repetition

scale.

than

This

those

needs

investigation.

tohospital admitted

.. .. ‘¿@2present Violence received .. Less than one year at2! address

294

..3315‘05

9•02

[email protected] We wish to thank Miss Dorothy Buglau, M.Phil., and Dr. Norman Kreitman (M.R.C. Unit for Epiderniological

Studies in Psychiatry, comments.

Edinburgh)

for their helpiW

140

CROSS-VALIDATION OF A PREDICTIVE SCALE FOR SUBSEQ@UENTSUICIDAL BEHAVIOUR

T@isnu@, M., BELLINI,P., TA000NI,A. & SIcI,.Lksn,0.

REFERENCES

Buoi.#iss,D. & Hoa'rox, J. (i97@a)A scale for predicting subsequent suicidal behaviour. British Journal of Piatr,, —¿

—¿

124, 573-8. (1974b)

The

aepetition

of

parasuicide:

a

comparison of three cohorts. British Journal of Psychiafry, 125, 168—74. —¿

&

McCuu.ocx,

viour:

J.

W.

the development

(i@7o)

Further

suicidal

and validation

beha

of predictive

scales. British Journal of Psychiatrj, iz6, 483-9!.

(i@7.,) Un sistema di archiviazione

del dati in

psichiatria: il Psychiatric Computing Facility. Iprimi tre anni di applicazionein una clinica psichiatrica universitaria. In Tecnic/ze di Automazione in Psichiatria (eds. G. B. Cassano, P. Castrogiovanni, P. Pancheri and M. Tansella), pp. 51-79. Roma: Ii Pensiero

Scientifico. Woiu..n HEAI.TH ORGANIZATION(1968) Prevention of Suicide. Health Paper 38. Geneva: W.H.O.

N. Garzotto, M.D., Roberta Siani, Social Worker, Christa Zimmermann Tansella,

Dipl.-Psych.,M.5c., Clinical P.@ychologut,

M. Tansella, M.D., Istituto di Clinica Psichiatrica di Verona, Università di Padova, Policlinico, 1-37100,

(Received 2! March ‘¿975)

Verona, Italy

Cross-validation of a predictive scale for subsequent suicidal behaviour in an Italian sample.

A six-point prodictive scale for parasuicide repetition developed by Buglass and Horton (1974a) was tested on a group of patients admitted for parasui...
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