Clinical research in aggressive patients, pitfalls in study design and measurement of aggression

Pergamon

CLINICAL RESEARCH IN AGGRESSIVE PATIENTS, PITFALLS IN STUDY DESIGN AND MEASUREMENT OF AGGRESSION MARIANNE Clinical

MAK and PAUL DE KONING

Pharmacology Department, the Netherlands.

Solvay

Duphar,

(Final form, May 1995) Contents

1. 2. 3. 4. 5. 6. 7. 7.1 7.2 7.3 8. 9.

Abstract Introduction Defining Aggression and Specifying the Research Targets Patient Selection Design of Studies General Considerations on Scales for Measuring Aggression Scales for Diagnosis and Determination of CareRequirements Scales for Measuring the Effects of Interventions Disease Independent Observer Scales Disease Specific Aggression Scales Selfrating Scales Scale Selection and Use of a Set of Scales Conclusions References

993 994 994 996 999

1002 1003 1005 1005

Abstract Mak, Marianne and Paul de Koning: Clinical Research in Aggresive Patients, Pitfalls in Study Design and Measurement of Aggression. Prog. Neuro-Psychopharmacol. & Biol. Psychiat. 1995,19(6):993-1017. 1.

2.

Experience from scale validation studies and from controlled drug trials provided clues for optimalisation of studies in aggressive patients. Definitions of target behaviour, selection of patients and measurement of aggression are reviewed and recommendations are presented.

Kevwords:

aggression,

scales,

design,

pitfalls

Abbreviations: Aberrant Behavior Scale (ABC), Brief Psychiatric Rating Scale (BPRS), Buss Durkee Hostility Inventory (BDHI), Clinical Global Impression (CGI), Carolina Nosology of Destructive Behaviours (CNDB), Disability Assessment Schedule (DAS), Diagnostic and Statistical Manual (DSM), European Rating Aggression Group Scale (GAS), Handicaps, Behaviour and (ERAG), Global Aggression Skills Schedule (HBS), Hostility and Direction of Hostility Questionnaire (HDHQ), Nurses Observation Scale for Inpatient

993

M. Mak and P. DC Koning

994

Scale (OAS), Positive and Evaluation (NOSIE), Overt Aggression Negative Symptom Scale (PANSS), Rating Scale for Aggression in the Elderly (RAGE), Scale for assessment of Agitated and Aggressive Behaviour (SAAB), Social Dysfunction and Aggression Scale (SDAS), Staff Observation Aggression Scale (SOAS). 1. Introduction

Aggression interest drugs

remains

been

tested

and validated

1990, Tardiff of scales

to-date

requires

belongs

validation

on

six

studies

encountered

and

aggression

In surveys

a

years

new

concerning may

to suicidal assaults.

areas of

requires maximal attention

clinical

research

compound

for

and

a

number

improve

of

the

involving independent

aggression,

This communication

the

authors

may help future

pitfalls

chance

and Soecifvinq aggressive

of

which progress

behaviour

and

The different to be included

for apparently

definition

by

behaviour

another individual

Bond

we in

opinions

to

may

from

variety yelling

lack of cooperation on aggressive

in the measurement

of and to

behaviour

of aggressive

of study results and may be one

provide

results.

a good

directed

global

basis:

by one individual

Ag-

against

(or object or self) with the aim of causing harm

(Bond 1992). A further is

from

Targets

a wide

ranging

inconsistent

is behaviour

for any investigational aim

the Research

behaviour

be encountered,

hamper the interpretation

of the reasons

if the

of

scale

avoid

thereby

behaviours

gressive

to

Asqression

and the symptoms

The

The study

purpose.

to

research.

2. Definins

behaviour

been

research

to the most difficult

anti-aggressive

of

researchers

physical

has

and Mak 1991).

report their latest experience.

screaming

experimental

scales

namely

hence the methodology

of a potential

problem

new

a new competence,

scale for a specific

reflexion

clinical

Several

of

choice

clinical research,

testing

variety

of

1992, Mak et al. 1994, Beth 1993). The broader

with aggression

(De Koning

a

a wave

et al.

available

in patients

and

despite

(Baumeister and Sevin 1990, Yudofsky

select the right

a

in psychiatry,

in this field over the last decade.

have

developed

As

a problem

operational project.

classify

specification

A broad approach

patients

with

will be required is more adequate

a view

to

minimal

or

995

Pitfalls in clinical aggression research

optimal

conditions

of

care

(Beth and

purposes more precise and restrictive ry, the type of restrictions

Mak

1994).

descriptions

being determined

For

scientific

will be mandato-

by the nature

of the

study. A number trasts

of options

have

will be discussed

to be considered.

or

inclusion

dysphoria

which

A dimension symptoms

Social

of aggression

Rating

and

others

physical

of the pathology, The

outbursts

or himself

behaviour, However,

occur

in a certain

may depend

aggression. aggression

et

only

information

1990,

the most

hence concentration isolating

on this

the acts from the may be part

and

the

nature

hurts an object,

another

only. of

the

person

on the circumstances.

of patients

bothersome,

patients

Such

This

of the

al.

are seemingly

of aggression in between

by the continuous

or by the perceived

patients

receive

high

as target

on aggressive

of research

threat

scores

behaviour

will

yield

scales,

aggressive

provocation

of

of physical on

scale. Hence, a choice in favour of episodes

aggression

sign.

studies

of and

1992).

context

the patient

it was found that the behaviour

other

severe

(Wistedt

used to teach the rating

acts may be extremely or

symptom

is like looking at the tip of the iceberg

In case studies,

staff

ERAG,

a series

and impulses which in many patients

e.g. whether

response

across

in validation

and

behaviour.

most common

Scale

Group,

anger

of aggressive

acts of aggression

hard end may offer advantages. emotions

irritability,

as the most

Aggression

part of aggressive

underlying

as

features

findings

Aggression

The observable

such

as the mildest,

against

Dysfunction

essential

acts

can be demonstrated

of the remarkable

European

point is the focus on aggressive

form the basic

aggression

one

con-

symptoms

with irritability

physical was

of

essential

here:

The first and most evident only

Two

a

global

of physical

a very

partial

in its full scope as perceived

by the environment. A second behaviour

point

is thematter

behaviour. between

In the suicidal

expressions In two

to be considered

large

of hetero-aggressive

latter

category

behaviour

of self destructive studies

in the description

and

investigating

versus auto-aggressive

a distinction

has

auto-mutilation.

behaviour

of a target to

These

have a different

the coherence

be made

between

two

basis. hetero-

M. Mak and I’. De KOIIIII~

996

aggressive was

shown

clearly

Suicidal

behaviours.

or

symptoms,

tendencies

these

rather

aggressive

represent correlated

are part of a complex of depressive

behaviour

may

dominate

in

or

common

like irritability

grounds leads

to

the

self-mutilation to obtain

conclusion

or

testing

patients

hypotheses

patients

which

heterogeneous,

may that

not

make

no

behaviour, separately

behaviour.

like epidemiologic

treatment,

many

sources

samples

generally

yet

could be proven.

must be measured

content,

are

patients

selection

concerning

There

same

periods,

hetero-aggressive

of the aggressive

of more scientific

is vital.

does

self-mutilation

in the

or dysphoria

3. Patient In studies

occur

that

picture

Although

alternating

and suicidal tendencies

a complete

self-mutilation

behaviour.

simultaneously

This

while

(ERAG 1992, Beth 1993). Self-mutilation

with suicidal

may

it

expressions

melancholia,

hetero-aggressive

and self-mutilation

or to some extent negatively

tendencies

fit into a syndrome

is not connected and

that

non correlated

independent,

really

suicidal

behaviour,

of

valid

the

selection

of variation

aggressive

conclusions

issues of

between

patients

so

can not be drawn

(Table 1). Table Possible

Patient

1

Selection

Criteria

DSM axis I or II diagnosis Direction of aggression : internal vs external Type of aggression : verbal, physical Frequency of aggressive attacks Severity of aggressive behaviour In-patients or out-patients

One

of

the

psychiatric (American The

diagnosis

relationship

be

between

diagnoses

diagnoses

and (DSM

in

Association

that aggression

treated

aspects

selecting

patients

on either axis I or II according

Psychiatric

psychiatric theory

critical

remains

III-R)

(Van

aggressive

behaviour

controversial.

to DSM-III-R

et

and

al

specific

At one end stands the

based disorder

independent Praag

the

1987).

is a biologically

investigated

is

of

possible

1990).

In

a

which axis study

can I of

Pitfalls in clinical aElgressionreswrch criminal

found

aggression

between

support 1989).

a

axis

I

this hypothesis

between

of studies,

aggressive

respectively

symptoms

diagnoses

however,

feelings

aggression,

independent

as

reported

could

which

behaviour

be

would

(Tuinier

et

al

during

a disease

scales

final truth

by the

1979;

Price

though

assessment

methods

possible

of symptoms

the

O'Kearny,

1982;

and the other core

suggesting

course

a connection

aggressive

are

groups

be-

thoroughly

Moreover

patients,

mentally

studied

and

different.

The

yet, but it is good scientific

major determinants

in advance.

assess too widely different

instruments

and

schizophrenia

showed a parallel

that the patient

is not at our disposal

to specify

and

and

feelings

episode,

patient

and

of symptoms.

be stated or

a clear correlation

mania

of each of these axis I disorders

It should

practice

have revealed

depression,

of

(Blackburn

tween the two types

manic

no relationship

and

et al, 1981). The aggressive

over time,

course

Netherlands,

of disease

symptomatology

Tsiantsis

the

the

(Table 2)

A number

total

in

997

in the pattern

or

be difficult

to

it will

like for instance

retarded

patients

aggressive

with

the

same

in one and the same study.

Table Controversies

2

in Aggression

Classification

I

<-> Disease dependent Aggression correlated with axis I or II diagnosis

Disease independent Aggression independent of axis I or II diagnosis

II

<-> Secondary aggression Aggression in context e.g depression, psychosis

Primary aggression Aggression predominant feature of disorder as in e.g. borderline or antisocial personality disorder

Heterogeneity

between patients

and the pattern The

of aggressive

distinction

mutilative

between

behaviour

on definition

is obvious also from the direction

behaviour.

hetero-aggressive,

has been mentioned

and specification

suicidal

already

of target

under

behaviour.

and

self-

the section

M. Mak and P. DC Konmg

998

The severity of

the

and frequency

behaviour As

patients.

attacks

hospitalized specifying

which

attractive.

vary

are

patients, a minimum The

entry criterion

of aggressive

authors

attempt

is

included. is poor. week weeks

easy to

as

well

as

to count,

reduce

at

used

frequency

between least

heterogeneity

of attacks per week or month, of aggressive

dubious,

The interrater Secondly,

problematic.

particularly

if

episodes

reliability

the frequency

The objectivity also

verbal

of scoring

varies

in by

may seem

for several studies to test an anti-aggressive

pound and found this approach criterion

within

supposedly

an

number

greatly

episodes are two aspects

as

com-

of this

attacks

are

verbal aggression

considerably

from week to

(Fig 1). To cope with this we chose a period of three or four and averaged

the number

of episodes.

Yet the fairly

sudden

drop, also in the placebo group, on entry into the double blind period gave the impression that the scores had been upgraded to reach the selection ding

is

criterion Depression the trial

known

criterion

also

is fixed

from

by

(De Koning et al. 1994). This upgra-

depression

a score

or a similar

on

studies

the

where

Hamilton

Rating

scale, hence this is a feature

the

entry

Scale induced

for by

design. Total number of ag (events scored wti 15 ,~.

ressive

events

per week

OAS) ______~________

14. 13. 12.

Aggressive

events

11~ 10. 9. 0~ 7. 6. 5. 4~ 3. 2. f. 0, -1

1

2

-

3

4

5

6

7

8

9

Week

Fig 1 Patient X, male, 24 years old. personality disorder. Treatment placebo.

Diagnosis:

antisocial

Pitfalls in clinical Severity

of aggressive

total behaviour a better rating

behaviour,

including

rrsearch

either

the situation

One could

criterion.

like the Global

aggression

of attacks

in between

use a global

Aggression

999

Scale

scale

or of the

attacks,

may be

for the severity

(Beth 1993, De Koning

et

al. 1994). In

the

choice

situation

of

their

can

of

patients

interpersonal

between

the

aggressive average

of

behaviour

four

approximately

is very

with

several

a good and and

to comply.

an

retarded

centres

the

will

sample the art is to find the right to reach

homogeneity

and a loose selection

example

may

patients, episodes

serve

our

with

entry

per

week.

approached

were

should probably

in a nutshell

most

A good

and investigators

resulting preventing

study

For

and

size

of

this

problems

160 an

study

ultimately

19

have been even stricter. the

of

criterion

(De Koning et al. 1994). The final conclusion

the selection

who

can be observed

difficult

not inclined

selection

aggressive

30

participated

Patients

estimated

between patients

of patients As

mentally

or

the

for such studies.

a rigid

conclusions.

aspect.

delinquents

measured

of a patient

in too small numbers valid

research

are hard to follow. Obtaining

relationship

In the selection balance

be

are by nature

have to be established

aggression

is a very important

patients

impression

aggressive

for

or institutionalized

behaviour

scales. Ambulant honest

population

of the patient

are hospitalized, and

a

was that

This depicts

in clinical

aggression

research.

4. Desiqn The

remarks

gating

the

studies different

effects

for

this of

other

heading

apply

therapeutic

scientific

only

to studies

interventions.

or

other

The

clinical

investidesign

of

follow

aims

rules.

On the basis eltoprazine

of our study

the authors

in aggression original

under

of studies

must

be

assumption

programme

are convinced double

that

patients

would

rejected

by the study

patients

with a diagnosis

blind

drug

show no or very results

with

the experimental

of one golden and

placebo

resistant

little placebo

severely response,

retardation,

studies

controlled.

of the larger studies

of mental

rule:

drug

The

aggressive was fully

in aggressive

schizophrenia

or

M. Mak antl I’. I)t’

1000

personality category

Hence the finding was not restricted

disorder.

of patients

placebo

response

scales.

This

tionink!

(De Koning et al. 1994, Mak et al. 1994). The

was

in the order of 30 to 60% for the different

implies

that

studies

concerning

will have to use double observer techniques distribution

of patients

The individual

of patients

be the

design.

behaviour

the behaviour Koning

of aggressive

and strictly randomized and a control group.

behaviour

chronic,

this

as required

scores nevertheless

spontaneous

effect,

which

measurements, situations

increase

(Nilsson

interpretations

and the limited

is probably

so.

The

for such a design,

but

not

show a basic declining

1994, Mak et al. 1994). This phenomenon

placebo

therapies

would suggest that a cross- over study may

Unfortunately

is usually

non drug

over an intervention

character

availability best

to one

fluctuations

and

the awareness

slope

may be a mixture the

effects

of certain

the

results

in such

trials

of of

provocative

et al, 1988). Drop outs may also disturb

of

(De

(Moriarty

the

et

al.

disorder

or

1994). Cross-over

designs

require

return

of

the

target

symptom to baseline. The example of neuroleptics withdrawal show that

a worsening,

proportion 1983).

of

Such

eltoprazine it remains

after

reactions

were

studies. difficult

aggression

number

centre

also

of aggressive

represents

et

seen

what the patient's

a worsening

in a fair

(Heistadt

incidentally

Given the variability

designs of

in

al. the

behaviour

basic

level of

a return

to the

carry

patients

their

required

own set of difficulties. in view

of the

The

inter-patient

is the most important problem. This will lead to multi-

studies

differences

may occur

level or a rebound.

The parallel

variability

a rebound,

discontinuation

to estimate

is and whether

spontaneous

large

suggesting

patients

studies

and

with

their

different

inherent

pitfalls

approaches

to

of

dealing

interrater with

acute

episodes. The use of concurrent as

basic

attacks, behaviour.

regimen

and

is a serious

medication,

usually

supplemented

with

handicap

in clinical

given over many years p.r.n.

medication

studies

for

of aggressive

Very often the nursing staff will refuse to discontinue

the co-medication,

despite evident inadequate efficacy.

this means that only effects of new interventions

In practice

on top of a basic

Pitfalls in clinical

(usually

regimen similar

consisting

to the situation

of

The

scientific

observation

period

type of aggressive the hospital without

delay.

patients

the start

makes

in first under

basically

short

lengthy

intention To test

discussions

with

the therapeutic

assessed

during

months

not

periods,

of

experience

year

we

the

nature

but

adequately. gave

interventions

up

the

many

in chronic

should be applied

of

and in

of symptoms

like

episodes.

Long

separate

in these trials, are a burden on the

are

of interrater

concerning also

hard

In open

violations

to

realize.

be very difficult

to

test

controlled

in

levels of coFrom

of double

long term studies as

Placebo

reliability

stable

that eight to twelve weeks

and co-medication. may

at

are also

variable

authors

and reduction

treatment

as needed

any

a long period

the

than weeks. The aim of treatment

The requirements

observed

such

incomplete

to assess

or treatment

of episodes

is a fair balance.

schedules

and

the

of therapeutic

rather

we estimate

treatment

to enter

such studies

are hard

staff and risk to incur more problems

medication

to

need treatment

are usually

experts

measure

this case is prevention

the assessments.

the

such studies.

patients

observation

to match

cases taken

impossible

is unethical

symptoms

and

of the study feasibility.

have

acute violence

Scientifically

control

the usefulness

irritability

measured,

consent cannot be obtained and data

lasting

to design

instance

study. Emergency

intoxications

of the treatment. Placebo

be

and practical

it virtually

and possible

problematic.

After

will

into a study. Informed

on diagnosis

can

periods and the duration

of unmanageable

This

1001

neuroleptics)

desirability

patients

because

researrh

in epilepsy.

The set up of the treatment has to balance

aggression

our

blind

up to one

medication studies

and the results

dose

over such

will

be hard

to interpret. The

question

of

baseline

nature of the aggressive some

warnings

placebo

will

are

side

sensitive

effects data

behaviour

warranted.

provide

check more carefully with

periods

In

an occasion existing and

to

like change

to

deserves general

the

a positive a

run-in

level

and

answer,

but

period

using

to try out the assessments,

complaints, allow

establish

which might be confused

statistical

from baseline.

to

handling

of

more

M. Mak and 1’. L)e Koning

1002

The use

of this

period

idea. As explained the

inclination

patient

above,

may

to

had an unexpectedly

the next

period.

blind

extend

the

may produce

The subsequent

may not

period

Selecting

regression

drop of symptoms

may provide

and

if the

the patients

to the mean on start

of the

(De Koning

et by

decrease full

the acute

treatment

picture

in

al 1994). Ratey et al (1991) have tried to reduce these effects the use of a variable

a confusing

be a good

may be too high

baseline

calm behaviour.

baseline

period

purposes

the scores obtained

exist

at an above average

double

for selection

length placebo run-in period. This may indeed

fall

period

in the scores,

but it does

and

incur

thus

may

a

not cover

delayed

the

placebo

response. The use of a double of the study offer

a theoretical

this will

Before

has

the

directly

by social desirability on

their

own

patients, display

Information

may

studies

on Scales

first:

for Measurino

of

Aagression

aggression

how to obtain

one

important

reliable

data.

The

from the patients are likely to be distorted aspects. Few patients will faithfully

aggressive

like mentally

aggressive

but for large multi-centre

measurement

to be faced

data gathered

in charge

of the studyperiods

fail.

Considerations

starting

system, where the person

has no knowledge

solution,

practically

5. General

problem

observer

assessments

acts.

Moreover,

retarded

behaviour

on aggression

several

and demented

categories

patients,

are not cognitively

report of

prone

to

competent.

in patients can be obtained

from three

sources: - Professional 24

hour

special

a

day

to

observation

The observer aggressive usually

Observation

institutionalized programmes

scales

events

including

of the Patient. This can be applied

and

patients

scales more

part

time

in

for children.

can be divided

also

and

over

using

into scales which more

indirect

descriptive symptoms

record

the

categories,

like

anger

or

irritability. - Information most

relevant

retarded

from Close Relatives source

patients

of

living

or Home Care Givers.

information at

home.

for Even

demented in

these

This is the or

mentally

situations,

Pitfalls in clinical aggression research

aggressive - Direct the

may

spouses

however,

be

the patient Information

use

attitudes

and

committed

attacks.

about committed

to

admit

frankly

This implies

from the Patient.

likely

which

addition

some

pose

but

reaction,

In

setting,

reluctant

how

is.

questionnaires

of

criminal

very

1003

indirect

avoid

there

standardized

for

on

the

interviews,

cases

questions

questions

are,

on

actually

clinical

asking

acts, schoolbehaviour

aggressive

in most

or

directly

and contacts

with

the police. The data obtained both

to match,

because

the difference

6. Scales

from the different

with

but no disease attempt

aggressive

The

entity, lay

(CNBD)

behaviour

features

(axis

moral/cultural

as

designed

displayed

to medical

with

(Table 3).

of

the

aim

with

of

Destructive to

and Hartwig

part

improve 1990).

codes

for

the

and a part of four axes to

diagnosis

biological

interview

classification

Nosology

(Eichelman

tools

a syndrome,

a special approach

of a descriptive

(axis A), psychological (axis

findings

and

C)

the

(axis D).

of this system, large surveys and a central

benefit

be required

purposes.

(standardized)

Carolina

was

background

For a maximum would

the

behaviour

B),

or

for a nosological

of treatment

consists

link this

pragmatic

is

which

types of aggressive

databank

as well

of Care Reauirements

is a symptom or possibly

this requires

a basis

and choice

system

scale

behavior

behaviours

prognosis

and Determination

a diagnostic

to

Behaviours

used,

fields the total range of measurement

system. As aggressive

One

be expected

in interpretation.

for Diagnosis

start

cannot

of the items or questions

In many psychiatric will

sources

to draw conclusions

Unfortunately

for scientific

and

such a data base does not exist

to our knowledge. A

more

gressive

down

to

earth

behaviour

care and special

and

realistic

purpose

is the use of scales

equipment,

housing,

to measure

on

behavioural

auto-aggressive full inventory

acts.

problems,

including

For emergency

is not very relevant,

the

need

agfor

etc.

Fairly often the need for institutionalization mostly

of measuring

depends

partly

hetero-aggressive

treatment

in an acute

but when prolonged

or or

ward

hospitali-

a

1004

M. Mak

zation

or

other In

important. coherence together

forms

those

and I’. De Konin<

of

care

cases

the

are

required

behaviour

with other mental or physical determine

this

has

becomes

to

be

quite

measured

symptoms or handicaps

in

which

the need for care.

Table Diagnostic

3

and Needs

Inventories

Application Diagnostic CNDB

All patients

Needs inventories NOSIE

Psychotic, Personality Disordered Patients Mentally Handicapped Patients

HBS, DAS

For

many

types

personality Inpatient

of

aggressive

disordered

patients,

Evaluation

30

items

social

in various

The authors tology

in

aggressive obtain

a

retarded

the expression

These

physical

patients

of

the

Systems

Handicaps,

Behaviour

and

the symptoma-

several

often

suffer

(HBS)

and

for

the

this

schedule

Assessment

Both are structured

is gathered

A more

the use of

items

do

not

with a high incidence

handicaps

Skills

This

from

specific

purpose of

the

Schedule interview

of

multiple

Special scales are available

designed

Council and the Disability et a1.1982).

as

will

below.

for rating

patients,

and mental.

picture

which information

behaviour.

forms of aggressive

would

are a population

required.

1980, Holmes

The factor irritability

to aggressive

as will be discussed

retarded

behaviour. good

manifest

require

conditions

Research

irritability,

found the NOSIE unsuitable

disturbances,

competence,

self or objects.

severely

apply. Mentally

social

of such behaviours

scales

for

countries

towards other persons,

assessment

observer

symptoms,

and depression.

who are inclined

acts eg. aggression

further

of

neatness,

not measure

or

Scale

et al. 1966). The scale consists

clusters

retardation

scale does, however,

elaborate

(Honigfeld

personal

to patients

psychotic

(NOSIE) or derivatives

seven

interest,

psychosis, point

in

like

Observation

may form a good basis of

patients, the Nurses

to

care

are

the

Medical

(DAS) (Wing systems

in

from one or more persons who know the

Pitfalls in rliniral

retarded

patient

behaviour

Scales

7.1 Disease

Indewendent of

any

block

1005

of

items

related

to

feelings

which

of scale

theoretical

and

whether

behaviour

the

the

which measures

disease

form

an

depend Although

observable

aspects.

should

study will depend

One

of them

be measured

or mental symptomatology.

population

is homogeneous,

specifically

pathology

is the

in the

of patients.

type. to the homogeneous

applicable

scales

such

populations

question of the

If the diagnostic a scale

may

If the patients

Obviously

on many

context

the broader or more detailed

the only

than

is complex.

for a particular

independent

applicable

will

tools applied.

evident

its

the reality

to this category

psychiatric

in

practical

total behavioural of

intervention

may lend itself better to to quantification

like anxiety,

The choice

therapeutic

is

of Interventions

Scales

of the measurement

behaviour

phenomenon

common

a

the Effects

Observer

on the adequacy

aggressive

ground

have

for Measurins

evaluation

heavily

Both

research

problems.

7.

The

well.

aggression

be

backchosen

behaviour

have a varied

will

methods

be of the are

also

(Table 4).

Table 4 Aggression

Intervention

Observer Scales: Event Scales Disease Independent Scales Desease Specific Scales Global Scales Self rating/questionaires: Patients General Population Oriented

Examples

of

the

disease

Effect Scales

: : :

OAS, SOAS, SAAB SDAS ABC, RAGE (PANSS, BPRS) CGI, GAS

: :

HDHQ BDHI, STAI

independent

scales

first and some of their inherent advantages

will

be

discussed

and disadvantages

will

be mentioned. The event

scales,

the most basic scales,

simply describing

each aggressive

type of scales for aggression.

developed

episode,

are

There are three such

in the same period by different

research

groups.

M. Mak and P. De

1006 The Staff Observation

Aggression

Koning

Scale (SOAS), the Overt Aggression

Scale (OAS) and the Scale for Assessment Behaviour

(SAAB)

1986, Brizer The

(Palmstierna

principle

of

these

aggressive

behaviour.

which

related

for children

gression

some

and adult

scales

were

patients

welcomed

researchers,

theoretical

extent

aggressive

for the recording

a

and Aggressive

Yudofsky

description

either

to

the

et al.

verbal

between the scales

populations

of intensive

separate

or

they

patients,

care

were

the OAS

wards

and

the

circles

of

ag-

delinquents. with

enthousiasm

in

as these scales would provide

of actual behaviours.

disadvantages

of

physical

for e.g. the SOAS for elderly

SAAB for severely The

is of

There are some differences

to

designed

scales

episodes

"eventsq',

primarily

1987,

et al. 1987).

aggressive

are

of Agitated

and Wistedt

reliable

tools

Over time the practical

have become clear. The practical

and

problems

are diverse. The completion

of the forms per event poses a heavy burden on the

nursing

staff

several

incidents

Secondly, training

particularly per

24

for heavily hours.

the interobserver

evident in verbal aggression, the content

The applicability have

This

to

be

to

raters have their

expressions

worst

even if

This is most

of discontent.

is also limited

The

with

underreporting.

is not very good,

where the different of verbal

regularly.

patients

or case vignets.

of the event scales

isolated

leads

reliability

is applied with video-films

own ideas about

aggressive

periods

if patients then

escape

recording. At

the

question event

level

of

statistical

arose whether

in one figure,

arbitrary

problem

studies

SOAS and a global correlation

and

used to summarize

information

the data per

of what

happened

of the event scales was encountered

of the SDAS, in which the original for concurrent

the total scores and the global

like the GAS scores, was very modest

the overall

the

for the OAS and the SOAS are not

scale were included

between

aggression

interpretation

patients.

important

the validation

in charge

the paradigms as proposed

and tend to hide the real

in individual Another

testing

impression

is based

just the aggressive

of aggressivity

to an important outbursts.

degree

OAS, the

validity.

on other

The

assessments

(ERAG 1992).

in the minds

in

of

Hence

of physicians symptoms

than

Pitfalls in clinical aggression research The

authors

have become

and researchers

aware

retrospective modification on the

record,

week

frequency

elements

and designed

of

the

OAS.

at the end of each week places

of aggressive

precision

events

a

This

emphasis

(Silver and Yudofsky

1991,

of the original event scales. Lately Coccaro

et al, 1991 have developed irritability

tients.

using

of the OAS

(1991). These week records are easier to use, but lack

the intended

symptoms

involved in the validation

a number of the difficulties

of

with scorings

Sorgi et al

1007

a modified

and suicidal

form of the scale

including

ideation, to be used for outpa-

The value of these modified

versions

remains

to be further

demonstrated.

The data

scales

in their

original

on the variability

contributing activities help

to

of aggressive

to the occurrence in the ward

design

information

with

nursing

including

items comprises

Two

to measure

Such

(Silver

of the

aggression

languages

coherence six

impaired

aggression.

of severity SDAS

have

Yudofsky

and Aggression

patient-

patients.

The

and negativism, The scoring

SDAS

as well

system

uses

(score O-4).

been

hetero-aggressive remained

a

with other symptoms. items

validated,

one

listing

studies

11

in six

as

which

closely

behaviour.

separate Suicidal resembles

(ERAG 1992). This sub-scale

depression scale,

and

day, may

and a broad range of patients all point to a valid q-item

for measuring

Self-mutilation

of

insight

across

items and the other with 21 items. Three validation

scale

of the

other scales may offer more

like irritability

or physical

categories

versions

in charge.

the Social Dysfuntion

cognitively

attitudes

as acts of verbal five defined

and the factors

to time

schedules

valuable

1990, ERAG 1992).

was developed

populations,

very

less effort.

(SDAS, Wistedt scale

behaviours

of interventions

Such a scale may represent

This

may provide

in relation

or personnel

optimal

1988). For assessment

Scale

format

there

are

better

scales

item,

lacking

impulses a

sufficient

fitted

scale

was deleted

for measuring

for

in a block melancholic

from the final depression

and

suicidality. The final version hetero-aggressive

of the scale consists behaviour

and

of the q-item

according

to

scale

relevance,

for the

M. Mak

1008

separate

item

for

auto-aggressive validated detected

selfmutilation

specific

can

for

for

scale

selfmutilative

the

average

in two fashions.

behaviour,

the

once for the behaviour

the

of

severity

between

added,

to estimate

the

behaviour

could

be

in the literature.

scores twice,

days

be

This is far from ideal, but no adequate

component.

The SDAS has been used score

and I’. Dr Koning

the

ratings

peak

is usually

in more acute

episode

between of

one week

The first mode uses one

second

application attacks

aggression.

and once for The

interval

but can be reduced

to three

cases.

The scale has a good interrater

reliablity

and a high correlation

between the total g-item score and a global assessment. coefficients

method

with the Global Aggression

0.75 to 0.85 for the general

Correlation

Scale were in the order of

or the average

scores

(Wistedt et al.

1990, EBAG 1992) One

disadvantage

adequately Another aggressive

account unsolved

of

problem

behaviour.

frequently

scale

is that

for the frequency

from hetero-aggressive were

this

the

of aggressive

is the balancing

In the eltoprazine behaviour

seen. An example

scoring

Table

and auto-

shifts over time

to self-mutilation is given

not

episodes.

of hetero-

studies

does

and the reverse

in Table

5.

5

Concurrent Use of SDAS and GAS in a 25 Years Old Schizophrenic Patient, Treated with Placebo over the Total Perid of 12 Weeks in a Double Blind Study of Eltoprazine.

week week week week week 4 6 a -4 0

Post

SDAS: Aggression towards staff members (0-4)

2

1

1

0

0

0

SDAS: Aggression towards non-staff (0-4)

4

3

2

3

2

0

SDAS: Selfmutation (0-4)

2

3

3

1

3

2

GAS: Global Aggression Scale (O-lo)

8

8

8

4

2

2

Pitfallsin clinicalaggressionresearch Unfortunately

1009

one cannot

rely upon global assessments to cope with this duality. Global asessments do not pay equal attention to outward and inward directed aggression. The hetero-aggressive behaviour dominates the picture. In an attempt to reduce this problem a double GAS rating was introduced in one of the validation studies. The result showed an acceptable correlation between GASoutward and the total score of the g-item SDAS scale (r=O.71), but a modest correlation between GAS-inward and the selfmutilation score (r=0.53) (Beth and Mak 1994). In our experience though, the SDAS is a valuable tool for measuring effects of interventions, which can be applied over long study periods, without posing too large a burden on the staff. The third category of disease independent scales form the global scales, as already mentioned above. In daily practice such a global impression of the patients behaviour will often form the basis for referral, for placement in a particular ward and for treatment. The more sophisticated assessments gain acceptance only slowly. There are several global scales: scales for measuring severity (of the behaviour or of the problem this creates), and scales for assessing change. The widely used Global Clinical Impression (CGI), as used for depression (Guy 1976) can also be applied to aggressive behaviour. Beth has proposed a 0 to 10 point Global Aggression Scale (GAS), (EBAG 1992). The advantage of the latter may be that it tends to "contaminate" less with the overall mental symptomatology than the CGI, because the CGI has been used in general for assessing total mental symptomatology. The anchored seven categories of the CGI, however, may have some advantage over the less circumscript categories of the 11 point GAS. These global scales have as drawback that the scores are very much dependent on the background of the raters. Judgement by the raters is made against their daily experience. A physician in charge of a department or ward with severely aggressive patients will tend to give lower global scores than a physician who only rarely faces an aggressive patient (Beth 1993). 7.2 Disease Specific Aasression Scales When patients with multiple behaviour symptoms besides aggression

M. Mak and I’. 11~ Koning

1010

subject

are

of

a

a more

patients,

integrated

to estimate

the results

specifically

designed

the

Aberrant

consisting

of

inventory

picture

hetero-aggressive

geriatric

0

to

developed

patients.

limited numbers data

look

studies and studies deals

exact

The

The

play

in

1985).

of

role

severely

This

gives of

scale

a broad

this

a more

and

non-

integral

importance

behaviour

in

is

the

of

total

the

(Pate1 and Hope frequency in

1992).

categories

the

validation

This has

institutionalized

authors

aim

behaviour

important

total

for

correlates

the differences

a less

of

scale is the Rating Scale for 21

been

aggressive

studies

included

most of these demented, the validation

observed

mentioned

factors

scales,

related

Gorham,1962;

Kay

is often

scale depends

7.3 Selfratinq most

aggressivity

scales

its use

at treatment

of aggressive and since

behaviour.

self-injury

is

between various dimensions

role

score

may

go

in the

like scales

in this have

field,

to

be

direction

for depression

like the BPRS and the PANSS to

hostility

et a1.1987). insufficiently

of the aggressive

The

use

The

psychopatholgy,

latter

scales

patients

use

majority

the

of a scale

yet

the

verified

in

studies.

above

measure

for

concerning

with

relevance

further

point

Although

rare in these patients, of aggression

(RAGE) 3

of patients,

convincing.

The scale

but

aggression

Elderly

using

specifically

for

advantage

auto-aggressive

specific

in the

scale

retarded

al.

the

the

problems,

and

Another disease

item

have

An example

5 subscales,

behaviours,

demented

is hard to determine.

symptomatology,

Aggression

et

over

or

picture may be preferable,

(ABC),

(Aman

spread

scales

behaviour

retarded

mentally

Checklist

items,

Such

of

for severely

abnormal

of

aggressive.

or detailed

patients

58

mentally

of an intervention.

Behaviour

retarded

mentally

like

study,

behaviour.

or

The

precise

to provide

items

(Overall

obtained

to

or and

in those

a good

The need to add a specific

on the objectives

scales

include

aggression

information

of

or psychosis.

picture

aggression

of the study.

Scales

common

type

of

selfrating

are the questionnaires.

scales

applied

The questions

to

measure

concern hostile

Pitfalls in clinical aggression rrsearrh

attitudes actual

and

aggressive

Inventory

to react

Direction

scale

and the

of Hostility

Multiphasic MC Kinley

subscales

were composed on factor

already

10 years

Inventory

construct

in 1957

verify

Hostility

(Buss and

Durkee

Hostility

(HDHQ), are derivatives

of the original

has been widely

data

do not

(Caine et a1.1967,

criticized,

more on face validity

analytic

but

later developed

Questionnaire

Personality 1951).The

aggressively,

The well known Buss Durkee

behaviour.

(BDHI) was published

1957). This

eight

impulses

1011

75

(Ramanaiah

of the

Hathaway

item BDHI

because

and internal

and with

the subscales

correlations

et al. 1987).

and

This was

than recog-

nized as a weakness

and lately a revised version has been published

by Buss

(1992) with

and

(physical revised been

Perry

and

verbal

scale

aggression,

the dichotomous

replaced

sensitivity

by

five

behaviours.

The

scale

punitive

intra punitive scale

1989).

been

the

original

system

to

to measure

scale

has

been some

between

items

Selfcriticism

BDHI

have

increase

the

outward

directed

(or intra punitive) and

five

subscales: Hostility

and Delusional

used

and

tested

and the sub-scales.

The

Guilt

as

Hostility.

for

the

findings

cor-

confirm

an outward and an inward directed et al. 1984, Miller the subscales behaviour

and Haffner

to a "general (see also

the

scales). that

the

differences used

and dichotomous

they would form General

is no uni-dimensional

fact

scale

51

is not to combine

on global

The

of

(Philip 1969, Arrindell

statements

quite

interesting

HDHQ

was

within

not designed individuals

extensively data

also

(Tsiantsis

as

over

a

in patients

et a1.1981;

"state"

time,

this

and

has

Price

and

1982).

selfrating

studies.

of the

In this

of Others and Delusional

of two dimensions,

as this

provided

hostility).

contrast

extensively

of the factors

The advise

O'Kearney

consists Criticism

scales;

hostility"

Despite

subscales

and

and inward directed

scales. Together

has

the existence aggression

four

the BDHI for questions

(extra punitive)

Acting out Hostility,

rectness

and

of the scale.

aggression

The

anger

scoring

was built on a presumed

as extra

29 items

answers

point

The HDHQ which resembles answers,

only

Cultural

scales

are

differences

not make

easy

to

use

it difficult

in

international

to translate

the

1012

M.Mak andP.De Koning

questions properly and often a full validation and adaptation of the

questions

is needed

to

obtain comparable

results

across

countries. This has been demonstrated clearly by Van der Ploeg et al.1980 for the Spielberger State-Trait Anger scale (Van der Ploeg et a1.1980, Spielberger et a1.1980). This scale has not been used sufficiently in patients to make a judgement on clinical relevance. A summary of advantages and disadvantages of various scale types is presented in Table 6. The statements should be balanced against the aims of the study and the relevant importance of certain features for a given project. Table 6 Aggression Scales Advantages and Disadvantages for Use in Psychiatric Patients OBSERVER SCALES Advantages

Disadvantages

All

Basis for intervention/evaluation

Interrater reliability (training required) Mainly for inpatients

1. Event scales

"Hard data"

Time consuming Often incomplete recording

2. Diseaseindependent

Use across diagnoses Core symptoms of aggression

Not adequate for inward aggression

3. Diseasespecific

Broad picture of behaviour

For limited population Role of aggression in total symptoms, value of total score

4. Global scales

Single score

Content of judgment unclear Interrater differences

Major relevance

SELF RATINGS/QUESTIONNAIRES All

Patients own information Suitable for out-patients

No real data on acts Social desirability Culture differences

1013

Pitfalls in clinical aggression research 8.

Scale

Selection

and Use of a Set of Scales

In the above sections have been discussed between

scales;

differ

measurement angle. and

the

results

accordingly.

of aggression

For

an

intervention

observer

mutilation

is

not

the

ideal

behaviour

behaviour

the

have

to be measured

considered

are the adapted OAS, or a selfrating

mental

disease,

choice

information point

the

is

limited.

self-

along

may be

Scales

scale,

with

to

be

if possible

from the care givers.

of the relation

authors

the scale

If

set of scales

In

Given the unsolved

of a global approach.

required.

with some additional

the

methods

hence

from more than one

best

a more elaborate

out-patients

various

scale,

a combination

is probably

or suicidal

with

one

has to be approached studies,

scale

hetero-aggressive

obtained

There

some of the differences

advise

to

studies a scale for the mental pathology,

between

include

aggression

and

in

intervention

particularly

for patients

with an axis I diagnosis. To achieve future event this films

an acceptable

raters scales

of aggression video-films

purpose. and

The

cuts

aggressive

of

a

to get

scales

was

The use

film The

made

train

miss

the

observer

of the events

training

material

to

of

life.

can be clarified

9.

numerous

problems

are the definition

commercial in

handling were

of the

surprise Case

for the SDAS

is easier,

the filmand

which vignets

and the

but

were

only

scales,

studies.

in description

in instruction

the

the

global

and in the eltoprazine

the weakness

case

challenge

all raters will never be realized,

items which

for

the instructions

in real

light

in

or subtitle

for the made

film

proprietors

element

bring

research

nurses

case vignets

discussions

Clinical

from

of the

area.

studies

between

We used

the

written

available

both in the validation good aggreement

scenes

with

from the

for each language

descriptions

to

handicaps

training

specifically

of

permissions

of carefully

is essential.

composed

rights and the need to translate filmscenes

reliability,

and case vignets,

video

patients.

difficulty

interrater

A

but the of

scale

material.

Conclusions

aggressive

to be overcome.

patients

is possible

Major points deserving

of the behaviour,

the selection

despite attention

of patients

and

1014

M. Mak and I’. I)(~ Koning

the choice

of scales

behaviour,

Hetero-aggressive tendencies tions

should

requires

unexpectedly

for the measurement

be measured

controlled

of the target

behaviour.

and

suicidal

self-mutilation separately.

studies,

Evaluation

as the placebo

of interveneffect

can

be

large.

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