1021 Pediatrics Joseph F. Fagan III, Lynn T. Singer ...

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Pediatrics. Joseph F. Fagan III, Lynn T. Singer, Jeanne E. Montie and Patricia A. Shepherd. Development in Infants at Risk for Later Mental Retardation.
Selective Screening Device for the Early Detection of Normal or Delayed Cognitive Development in Infants at Risk for Later Mental Retardation Joseph F. Fagan III, Lynn T. Singer, Jeanne E. Montie and Patricia A. Shepherd Pediatrics 1986;78;1021

The online version of this article, along with updated information and services, is located on the World Wide Web at: http://pediatrics.aappublications.org/content/78/6/1021

PEDIATRICS is the official journal of the American Academy of Pediatrics. A monthly publication, it has been published continuously since 1948. PEDIATRICS is owned, published, and trademarked by the American Academy of Pediatrics, 141 Northwest Point Boulevard, Elk Grove Village, Illinois, 60007. Copyright © 1986 by the American Academy of Pediatrics. All rights reserved. Print ISSN: 0031-4005. Online ISSN: 1098-4275.

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Selective Screening Device for the Early Detection of Normal or Delayed Cognitive Development in Infants at Risk for Later Mental Retardation Joseph and

F. Fagan

Patricia

III, PhD,

From the Department

ABSTRACT.

The present

study

tested

the

predictive

va-

device The

for the screening

early de-

vice, administered between 3 and 7 months of age, is based on the infant’s differential fixation “to novel” over previously shown pictures. The sample was composed of

(IQ

70) at 3

scores layed

correctly children.

normal

for later mental retarcognitive development years of age was 13%. Novelty preference identified six of eight (75%) of the deThe test identified 49 of 54 (91%) of the

children.

was 55%. 96%. The

specific,

Validity

Validity screening

and

to be at risk of delayed

for predicting

cognitive

delay

for the prediction of normality was device proved to be equally sensitive,

valid

when

the

sample

was

divided

into

infants born at term or born preterm. The results of the present study and of a previous study indicate that detection of cognitive delay based on early novelty preferences is as easily accomplished for infants who will later be mildly delayed (IQ scores 60 to 70) as it is for those who will later be severely delayed (IQ scores 50). Moreover, such results are in contrast to those obtained with con-

ventional atrics

tion,

tests

tapping

sensorimotor retardation,

1986;78:1021-1026;

memory,

development. screening,

Pedicogni-

novelty.

T. Singer,

Case Western

fixation

to

among

the

predictive device delay. between infant’s

validity

presents

at 3 years

initial of age

data

on the

of a screening

for the early identification of later cognitive The screening device, which is administered 3 and 7 months of age, is based on the ability to recognize visual stimuli. Visual

recognition novel” over

is measured previously

by differential shown pictures.1

fixation Differential

“to

infant’s

pictures

developing

information.

MA,

Cleveland

previously

the

infant

being

shown

memory formance able

ability

To

the

processes on later

to

shown can

pictures

discriminate

and

can

remember

that

memory

to individual fact, individual during

infancy

individual

during

have

of

risk

would

prenatal

on

be

due

to

prefer-

device

suspected Suspicion

presence

(eg,

is to

potentially

of infants

the

linked

novelty

retardation.

factors

of

research for later

from

groups mental

or peninatal

are

screening

normal

within later

In

of our device

early

the

potentially

nec-

related

to be predictive

preferences

based

infants

be

later intelligence. in novelty preferences

shown

of

in

would

a major goal a screening

purpose

for

and

differences

in

been

deficit The

to retain

perceptual

infancy

functioning.2 early novelty

to later intelligence, has been to develop intellectual

and

that

differences differences

later intelligent Given that

ences.3

to perceive

extent

tests of on the

are necessary for successful perinteligence tests, it seems reason-

suppose

ognition

of

various

extreme

prema-

turity).

The the

rationale

metric

for

for choosing infant

of, normative

bility

screening

of the

previously.3 problem

to one

two

standard

basic

consists following

of the

approach assessment

on, have

of a pairing a standard

details

and been

the

melia-

discussed of

problem.”

the Each

of two period

as on the

component

is a “novelty

immediately

Our

data

the

preferences

and

device

Briefly, procedure

novelty

novelty

intelligence

construction

screening Received for publication June 27, 1985; accepted Feb 26, 1986. Reprint requests to (J.F.F.) Department of Psychology, Case Western Reserve University, Cleveland, OH 44106 PEDIATRICS (ISSN 0031 4005). Copyright © 1986 by the American Academy of Pediatrics.

University,

over

that

differentiate

study

E. Montie,

the picture previously seen. In other words, visual novelty preference yield information

deficient

present

Jeanne

Reserve

novel

demonstrates

to be at risk

The

PhD,

PhD

of Psychology,

lidity at 3 years of age of a screening identification of later cognitive delay.

62 infants suspected dation. The prevalence

Lynn

A. Shepherd,

stimuli of study

stimuli.

to the

development of

individual

of a practical differences

PEDIATRICS Vol. 78 No. 6 December 1986 Downloaded from pediatrics.aappublications.org at Cleveland Health Sciences on February 8, 2012

in

1021

early recognition particular length less

than

memory of study

necessary

for

was time,

to allow a length

asymptotic

infants somewhat

novelty

a

or familiar,

which

necessitated

prefer-

initial

sessions.

The

result

of all this

effort

with

was

a

sample

years years

The

sample

for

the

12-

item test by conducting a longitudinal study using a sample of 92 infants with recognition tests administered at 52, 56, 62, and 69 weeks of conceptional age. Infants in the normative sample showed significant

visual

preferences

for novelty

on each

of

the 12 novelty problems. Finally, the screening device, known as the Fagan Test of Infant Intelligence, proved to have concurrent validity because groups of infants at risk for later intellectual deficit in the study by Fagan and Singer3 performed less well on the test at 3 to 7 months of age than did the 92 normal controls. The present study followed the same high-risk infants originally tested by Fagan and Singer3 to 3 years of age in order to estimate the predictive validity of the screening device. Specifically, we wanted to know if children who did poorly on the Fagan test as infants would also exhibit delayed cognitive development at 3 years of age. Delayed cognitive development at 3 years of age was operationally defined as an IQ score of 70 or less on a standard test of intelligence. Although the predictions from the infant tests have only been followed to 3 years of age, thus far, it is highly likely that

1022

and

delayed

at 3 years for example,

more

than

cog-

will still be has shown

400

childen

that

tests at ages of .65 to .73).

6 to 9

METHODS

was composed for later

mental

ofpmematunity (birth growth retardation,

weight treated

suspected

retardation

as a result

.90.

screening

device

administered

to

each three

infant was composed of 12 novelty problems, of which were administered at 52, two at 56,

four

at

62,

and

three

at

69 weeks

of conceptional

age. Specifically, the 12-problem novelty test included three pairs of abstract, black and white patterns that differed from one another along a variety of dimensions constituting three novelty problems at 12 weeks. Study times of 60 seconds were allowed for each problem given at 12 weeks, ie,

the

infant

looked

before it was paired two pairs of abstract used

as novelty

problems.

variety of dimensions 16 seconds to study prior to its pairing of the

pair.

for

The

60

seconds

with a new picture. black and white One

pair

at

a target

At 16 weeks, patterns were varied

along

a

and infants were only allowed one of the pictures in that pair with the other (novel) member

second

problem

at

16 weeks

con-

tamed two targets differing solely in arrangement of internal pattern elements. Infants were allowed 60 seconds of study for the second problem at 16 weeks. At 22 weeks, two sets of achromatic face photos (man v woman, woman v baby) with study times

of 40 seconds

and

two

pairs

COGNITIVE DEVELOPMENT Downloaded from pediatrics.aappublications.org at Cleveland Health Sciences on February 8, 2012

of abstract

pat-

temns

varying

study

times

in

arrangement

of

of 30 seconds

decreased

to

20

were

seconds

per

elements

used.

problem

delay

with

Study

times

at

weeks

29

when three pairs of face photos were used, including two pairs with achromatic photos of women and one pair of chromatic prints of babies’ faces. Every

attempt

was

made

to

test

each of the four ages (12, 16, corrected age), but more infants

weeks

29

than

were

seen

22,

at 12 or 16 weeks

referrals. In the final analysis, included in the sample if they seven of the novelty problems.

tion with

ensured at least

The

scone

an test

infant given

assigned

infant

scores

due

infant

to

twice

on the

Fagan

preference score. shown a new and

For exa pmevi-

ously seen pattern and devoted 10 seconds ing time to the new pattern and six seconds

of lookto the

with

old pattern,

>70

to the

his

new

problem. divided a mean

on her

pattern

percentage

of total

fixation

be

or 63%

for

would

10/16

Intellectual

outcome

by

the and

Peabody giving

tests.

If

the

were

was

by

estimated

were

formed

as an

RESULTS The

Bayley

unaware

age

sample

the

L)7 two

55%,

the

who ad3-year-old

child

had

per-

novelty

Sensitivity

The and

of Cognitive

Delay

incidence

Specificity

at 3 Years

preference IQ at 3 years 135). Delayed defined as an

for

Specificity Predictive Predictive

prediction to delay

to normality validity for delay validity for normality

pmef-

IQ of 25 had

were whose

also

mepme-

IQ scores

were

at risk

were

predicted

indeed

at 7 months

delayed

at 3 years

>36

weeks)

and

those

born

preterm.

to thrive.

The

Visual

Novelty

Preference

incidence

at 3 years

of delayed

cog-

of age was 40%

(eight

< 70). Novelty Given

preference

at 3 to 7 Months

scores

of Age

for

the

of Age

Delayed Normal Sensitivity

the

children

54 children

nitive development of 20 had IQ scores

All Children (n=62)

prediction

with

six of 11 infants

to be

Intellectual

Risk

child

delayed the

because

as failure

of cognitive of Tests

Novelty

In an earlier study,9 a preliminary version of the Fagan Test of Infant Intelligence consisting of four novelty problems was administered between 5 and 7 months of age to a group of 20 infants diagnosed

DISCUSSION a mean

68. The

eight

among

(gestation

yielded

13%.

of age. Validity for the prediction of normality was 96%, ie, 49 of 51 predicted to be normal were later found to be normal. As one can see from the data presented in Table 1, the screening device proved to be equally sensitive, specific, and valid when the sample was divided into those infants born at term

IQ score on

the

of age

Mental

an

technicians tests to the

of how

of 70 or less. 1.

(Form for the

attained

score of 59.5% (SD 8.1) and a mean of age of 96.3 (SD 23.1, mange 25 to cognitive development at 3 years was

TABLE Prediction

asand

of

and

the The

was

infant.

AND

IQ score

age

Scales

administered dividing

chronologic age. the intelligence

children

of

was

at 3 years of age. High sensitivity in predicting delayed cognitive development was not accomplished at great cost to specificity for normality, because the test also correctly identified 49 of 54 or 91% of the normal children. In the present sample, the validity of the screening device for predicting cognitive delay was

that

Stanfomd-Binet6

Vocabulary Test a mean IQ score the

Development8

3 years the

Picture child

necessary,

test by ministered

at

administering

at 3 years

of 25 and

sented

The sum of these percentages to novelty by the number of problems received yielded novelty preference score for each infant.

sessed

70)

a median novelty preference score of