Supplementary Carrying Compared With Advice to Increase Responsive Parenting as Interventions to Prevent Persistent Infant Crying

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Supplementary

Carrying

Compared

With

Advice

to Increase

Responsive

Parenting

as Interventions

to Prevent

Persistent

Infant

Crying

Ian St. James-Roberts, PhD*; Jane Hurry, PhD; Josephine Bowyen, BSc, RSCN; and

Ronald G. Barr, MDCM, FRCP(C)

ABSTRACT. Objective. To compare two

interven-tions (supplementary carrying, increased parental

re-sponsiveness) introduced from birth for their

effective-ness in reducing the amounts of crying in general

community infants at 2, 6, and 12 weeks age.

Design and participants. Mothers and infants in

new-born wards of maternity hospitals were assigned to

car-lying intervention, responsiveness intervention, or

con-trol groups. Follow-up measures were used to confirm

that the interventions were implemented and to

deter-mine their effects on infant crying.

Setting and measurements. Diary measurements

com-pleted in the home were employed to measure the

as-pects of parental behavior targeted by the interventions.

Audio recordings, diaries, and questionnaires assessed

the amounts the infants cried and the impact of the

crying on their mothers and the health services. Sample

sizes at 6 weeks of age were 59 (carrying intervention), 57

(responsiveness intervention), and 94 infants (control

group).

Results. The carrying intervention successfully

in-creased the amounts the infants were carried, particularly

while settled, to the target levels. The responsiveness

intervention led to more limited increases in carrying

and to a modest increase in feeding frequency, but did

not affect measures of parental interactiveness and play.

No differences in amounts of crying and fussing were

found between the three groups of infants on any of the

measures. Subsidiary analyses confirmed that the

depen-dent variable (infant fuss\crying) and main independent

variable (carrying while settled) were not significantly

correlated.

Conclusions. It is not, at present, possible to

recom-mend either supplementery carrying or increased

paren-tal responsiveness as primary, preventative interventions

to reduce infant crying. Pediatrics 1995;95:381-388; infant

crying, colic, state regulation, carrying, preventative intervention.

Persistent infant crying is stressful for parents, has

been linked to infant abuse,1 and is among the most

common reasons for health service referral during

infancy.2 The exact referral rate depends on several factors, but 21 % of families sought referral for this

From the *Depa,.nent of Child Development and Primary Education, and flhomas Coram Research Unit, London University Institute of Education;

and the §Departments of Pediatrics and Psychiatry, McGill University-Montreal Children’s Hospital Research Institute, Montreal, Quebec, Canada.

Received for publication Jan 5, 1994; accepted Jun 29, 1994.

Reprint requests to (I.St.J.-R.) Thomas Coram Research Unit, 27 Woburn Square, London WCIH OAA, United Kingdom.

reason in a recent United Kingdom study.3 There is

objective evidence that the referred infants cry

sub-stantially more than average,4 and their parents

ne-port continuing behavior problems at 3#{189}years.5 The

phenomenon therefore has a broad impact and is

costly for the primary health services.

Three main forms of intervention have been used

to prevent or treat excessive infant crying.6 Among

pharmacologic treatments, only dicyclomine

hydno-chloride has proved reliable, but possible reactions

and fatalities have led the manufacturer to

recom-mend against its use with infants. Based on the belief

that the crying reflects digestion-related

gastrointes-tinal pain (colic), a second approach has been to

target infant formula, or maternal diet for infants

who are breast-feeding, as a source of protein

intol-enance. Two carefully controlled studies have shown

that a hydrolyzed casein formula reduces crying in

some infants.7’8 Although this research is promising,

it seems unlikely to provide a general solution. For

one thing, although the exact prevalence of protein

intolerance is unknown, it appears to be rare,

occur-ring in 2% to 4% of infants, compared to a general

referral rate for persistent crying of approximately

15% to 20%. Except for dietary change, there is no

independent method for distinguishing the

intoler-ant infants. A further consideration is that the treated

infants appear to improve, rather than to normalize,

and their crying continues intermittently.7

Stemming from the view that parental styles of

care contribute to infant crying, the third approach to

intervention has been to target parental behavior. In

a controlled, randomized trial in a community

sam-ple, Hunziker and Barr9 showed that an average

increase of 1 .8 hours per day of carrying from weeks

4 to 12 resulted in substantially and consistently

reduced levels of fussing and crying, with an

espe-cially marked reduction (54%) in the evenings at 6

weeks. Several features of this study are noteworthy.

First, it sought to obtain direct measures of crying,

both at baseline and during supplementary carrying,

using validated 24-hour diaries kept by the parents.

Second, using the same diaries, it provided evidence

of changes in the target parental behavior (carrying)

in the experimental group. Third, the study involved

a self-selected sample, in that 50% of the parents

invited to participate declined to do so. This does not

affect the internal validity of the findings because

randomization to carrying or control groups

oc-curned after agreement to participate. However, it

at Viet Nam:AAP Sponsored on September 1, 2020 www.aappublications.org/news

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Nonintervention Responsiveness Intervention Carrying Intervention

leaves open the question of whether the findings are

applicable to the general community. A subsequent

study1#{176}found that supplementary carrying was

inef-fective as a treatment for persistent crying, that is, in

cases in which crying problems had already begun.

As an alternative to supplementary carrying, other

researchers have sought to modify parental

“respon-sive cane.” Taubman1112 asked parents to increase the

flexibility and amount of care and stimulation they

provided. This proved more successful than

neduc-ing stimulation11 on eliminating cow or soy milk.12

McKenzie13 found that hospital admission and

re-duced stimulation lessened crying problems in a

sub-group of infants referred for excessive crying, which

appears inconsistent with Taubman’s results.

How-ever, because McKenzie’s approach seems designed

to make stimulation more sensitive and contingent,

the inconsistency may be more apparent than real.

Both Taubman’s and McKenzie’s studies involved

treatment of selected infants presenting with crying

problems, rather than preventive interventions.

Nei-ther study presented direct evidence that the parents

used the interventions, so that the characteristics of

parental behavior associated with crying, and/or its

improvement, are unknown. McKenzi&3 considered

that it was impractical to ask parents in hen study to

keep diaries, so that only parental reports of problem

improvement were obtained. Taubman12 did obtain

parental diary measures of infant crying and

ne-ported a poor match between such diaries and

parents’ global reports of crying problems.

Although several issues remain, these studies

sug-gest that interventions aimed at the amount parents

carry their babies, and the way they interact with

them, are likely to be effective in reducing infant

crying. For primary health cane purposes,

interven-lions of this sort have an obvious appeal, because it

should be possible to incorporate them into standard

preventive programs with a minimum of extra cost.

In addition, such interventions provide a powerful

source of information for child development theory.

As well as parental variables, persistent infant crying

has been attributed to a number of infant

constitu-tional factors, so that evidence for a significant effect

TABLE 1. Characteristics of the Samples

of parental behavior will help to delineate the

impor-tance of such factors.

The present study was designed to compare the

effects of two interventions (supplementary carrying;

increased responsive care) with the results obtained

in a nonintervention control group. To maximize the

effects of the interventions in preventing persistent

infant crying, they were introduced as soon as

pos-sible after birth. A general community sample was

targeted to enhance the generalizability of the

find-ings. To distinguish between infant crying and

pa-rental perceptions of crying, crying was measured by

three different methods (tape recordings, maternal

diaries, and maternal questionnaires).

Samples and Procedures

METHODS

The study design required newborns to be assigned with equal likelihood to three conditions (supplementary carrying, increased responsive care, and nonintervention control) and to be compared on measures of crying at subsequent ages. The subjects were drawn from three London maternity hospitals, one serving a predominantly upper- to middle-class community and two serv-ing middle- to working-class communities. Multiple births and infants admitted to Special Care were excluded. The use of con-ventional random assignment procedures was problematic be-cause mothers in the different conditions might be in the same hospital ward at the same time, resulting in contamination be-tween the interventions. To counter this, the study was run in three phases. In the first phase, successive mothers in each hospi-tal were invited to help study individual differences in infants’ crying by completing diary and questionnaire measures. Over a 6-month period, 217 mothers were approached within the first 3 days after birth, 200 of whom gave written informed consent to participate in the study (Table 1). These mothers and infants formed the nonintervention control group.

In the second phase, successive mothers in hospital I were invited to participate in a study of the use of supplementary carrying to prevent excessive infant crying (carrying intervention), while mothers in the remaining hospitals were invited to take part in a study of responsive parenting with the same aim (responsive-ness intervention). After 3 months, the two interventions were reversed between the hospitals, and an equivalent number of mothers was approached. Eighty-two mothers were approached for the carrying intervention, 70 of whom agreed to take part.

Seventy mothers likewise agreed to participate in the responsive-ness intervention out of 85 approached. The sample sizes were calculated to have 80% power in correctly identifying a reduction

No. approached

No. recruited

2-wk assessments Overall no. Mean age, wk

No. boys

No. first-borns 6-wk assessments

Overall no. Mean age, wk

No. boys No. first-borns No. audio-recorded

I 2-wk assessments

Overall no. Mean age, wk No. boys No. first-borns 217 200 126 1.8 68 (54%) 91 (72%) 94 6.7 51 (54%) 67(71%) 25 (27%) 69 13 40 (58%) 42(61%) 85 70 64 1.8 33 (52%) 41 (64%) 57 6.1 29 (46%) 36(61%) 21 (36%). 34 14 17 (50%) 19 (56%) 82 70 62 1.9 32 (52%) 38(61%) 59 6.4 32(54%) 38 (64%) 13 (22%) 45 13 24 (53%) 27 (60%)

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of 30 minutes of crying time on diary and audiotape measures

(P < .05).

Both intervention groups of mothers were approached in the hospital within 3 days of delivery. They were asked to begin the

intervention immediately and to continue until the baby was at least 6 weeks old. Carrying-intervention mothers were given pro-prietary “baby slings” made of soft material to assist with carrying their infants and, following Hunziker and Barr,9 were asked to increase the amount they carried their babies to a minimum of 3 hours per day in addition to the carrying involved in feeding. It was emphasized that carrying should occur whenever possible throughout the day and not just in response to crying. Carrying could occur either in or out of the baby carrier, and the mothers were invited to share carrying with others, as they saw fit. The mothers were told that carrying had proved effective in a previous study in reducing crying.

Responsiveness-intervention mothers were given an attrac-tively printed leaflet which described the successful use in previ-ous research of increased responsiveness as a treatment for crying. The leaflet contained a simplified list of Taubman’s” recommen-dations, which the mothers were asked to use, as follows:

1. Try never to let your baby cry.

2. In working out the reason for his/her crying, consider the following possibilities.

That baby is hungry and wants to be fed. That baby is not hungry but wants to suck. Baby wants to be held and cuddled.

Baby is bored and wants some stimulation-singing, smiling, talking, or play.

Baby is tired and wants to sleep.

3. If the crying continues for more than 5 minutes of using one approach, then try another.

4. Work out your own way of exploring all the possibilities above.

Mothers in all three groups were contacted again when their babies were 10 to 14 days old. Control-group mothers were mailed diaries and questionnaires and were telephoned to provide help and reminders, as necessary. For the intervention groups, the mothers were telephoned and visited at home to confirm that they were using the intervention and to maintain their commitment to the research. As with the control group, the mothers were asked to provide diary and questionnaire measures at 10 to 14 days.

Six to eight weeks after each baby was born, each mother who participated at 2 weeks was recontacted to provide a second set of diary and questionnaire measures. As at 2 weeks, intervention subjects received home visits, whereas contact with control sub-jects mainly involved mailings and telephone calls. Follow-up measurements were completed when each infant was 12 to 14 weeks of age, using mailings and telephone calls in all cases.

In addition to the diary and questionnaire measures, a sub-sample of mothers in each of the three groups was asked to allow 24-hour home audiotape recordings of their babies’ crying at 6 weeks of age. These cases were selected at random by researchers unaware of the babies’ crying levels within the first 10 days after birth. Approximately one in four infants in each group was visited and audiotaped in this way (Table 1).

Crying was measured at 2, 6, and 12 weeks of age because it is at its maximum in the first 3 months, showing a peak-most pronounced in the evenings-at approximately 6 weeks of age.14”5 Two of these ages (6 and 12 weeks) compared closely with those studied by Hunziker and Barr,9 although it should be noted that the mean age of the present infants at the 6-week assessments-6.1 to 6.7 weeks-was slightly greater than that of Hunziker and Barr’s infants, who were in their sixth week. As Table I shows, subject attrition occurred, particularly in the control group in the first 2 postnatal weeks. Attempts were made to recontact 65% of the nonintervention mothers who failed to return the 2-week questionnaires. Fourteen (29%) were adamant that they had not received the questionnaires or had completed and returned them, implicating mailing difficulties. Because this stage of the study coincided with widely publicized mail service problems, this ex-planation may be valid. The other major reason given was baby illness (11% of the mothers), whereas a few mothers provided idiosyncratic explanations or were untraceable. Approximately half (54%) of the mothers contacted refused to continue in the study or failed to respond to repeated contacts. A previous study’6 found that attrition in keeping crying diaries was

re-lated to low maternal age and socioeconomic indices. In the present case, attrition in the intervention groups was due to infant illness, family hoidays at the study ages, or unwilling-ness to continue in the study.

Measurement Methods

The three main methods used in crying research (audiotape recordings, parental diaries, and parental questionnaires) show significant but moderate agreements, indicating that they measure overlapping but somewhat distinct phenomena.’7 Audio record-ings provide the most objective measures of crying vocalization but are insensitive to nonacoustic aspects of distressed behavior. Such “fussy” or “fretful” behavior is important for parents and makes up a substantial proportion of the overall fuss and crying reported in parental diaries. The diaries provide a reliable index of parental perceptions of distressed infant behavior. Questionnaire judgments of the amount of infant crying, whether it is a problem, and whether it has improved are more susceptible to subjective biases. Such measures are clinically important because it is

neces-sarily parents who seek health service referral because of problem infant crying. To consider each aspect of infant crying, we used three separate methods in the present study.

24-Hour Audiotape Recordings

Infant vocalizations were recorded continuously throughout a 24-hour period at 6 weeks, using calibrated Audio Ltd FM ra-diomicrophones built into soft (teddy bear) toys. The transmitted

signal was recorded on Uher model 4400 tape recorders fitted with voice-activated switches. A “speaking clock” recorded the exact time of each vocalization, together with an audible tick at 1-second intervals throughout the vocalization, on the second audiotape channel. It was thus possible to identify the precise time of day and duration (in seconds) of each vocalization. The mothers were told that they need not restrict their normal movements, as the radiomicrophones had a range above 100 m. The need to keep the teddy-bear transmitter near the baby was stressed; the teddy bear

included a carrying strap for use when the baby was carried. When the babies were taken for outings, the mothers noted this in their diaries. The researchers returned 24 hours after starting the recording, reviewed the recording period with the mother, and removed the equipment.

The resulting audio recordings typically occupied 2 to 4 hours of 6-hour audiotapes (only four recordings lasted 6 hours). The tapes were later transcribed and coded by trained researchers, using predefined criteria to identify periods of fussing and crying. To confirm their reliability, five audiotapes were transcribed in-dependently by two researchers, and two further tapes were tran-scribed by the same researcher at an interval of I month. Agree-ment was exact in each case for the overall measures of fussing or crying periods reported here. A more detailed account of the procedures used in recording and transcribing the audiotapes is given elsewhere.4

24-Hour Diaries

The mothers prospectively completed 24-hour diaries of infant and parental behavior based on those used by Barr et al.’6 The diaries were in the form of a time ruler, so that successive periods of behavior were shaded in against a time scale, with a resolution of 5 minutes of time. Infant behaviors (crying, fussing, awake-content, feeding, sleeping) were entered on the top section of the ruler to show the sequence of successive periods spent in the different behaviors. Parental behaviors, including care (changing, bathing, dressing), holding/carrying, and playing/talking, were shaded in on the bottom section of each time ruler. As with infant behaviors, parental behaviors were thus recorded for durations, frequencies, and sequences.

The mothers were asked to keep the diary for at least I day (corresponding with the tape recording when applicable) and for 3 successive days at each age if possible. Approximately two thirds of the mothers kept the diaries for 3 days, with most of the remainder keeping them for a single day. Each diary included

instructions and a sample diary, which showed how the diary should be filled in. It was emphasized that this was for illustrative purposes only, as the duration and sequence of behaviors would be particular to each baby and the parents. Pilot work showed these procedures to be successful in explaining how the diary

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should be used. Barr et al’6 provided further details on the use of diaries to record infant and parental behavior.

Crying Patterns Questionnaire

This questionnaire was developed to provide a quick and gen-erally applicable survey instrument for measuring parents’ per-ceptions of crying and its impact.3 Unlike the diary, it requires parents to recall and summarize crying over the previous week, so that subjective information processing is involved. Three of the seven Crying Patterns Questionnaire questions were used for the present study. Question I asked study mothers to summarize the total amount of fussing and crying (in minutes or hours) that occurred in the morning, afternoon, evening, and night of the previous day, or in the previous week if the baby had a regular crying pattern. Question 6 asked the mothers to record the number of times they found crying to be a problem or to be upsetting in the last week. Question 7 asked them to identify any health profes-sionals they had approached because of infant crying in the last week or last month. The answers to these questions are assumed to reflect maternal, social support, and health service variables as well as infant crying.’7 The information was collected to show whether the study interventions lessened the impact of infant crying on mothers and on the health services. The methods used were approved by the participating hospitals’ ethics committees.

Statistics

Because group differences at each age were the main concern,

the principal statistical method used was one-way analysis of variance, with Duncan’s multiple-range test between pairs of groups when applicable. To increase reliability, we averaged the diary data across the diaries available for each infant at each age.

Parental Behavior

RESULTS

Effects of the Interventions on Amounts of Infant

Holding/Carrying

Table 2 provides summary figures and analysis of

variance statistics for the diary measures of 24-hour

carrying/holding for each of the three study groups

(carrying intervention, responsiveness intervention,

nonintervention control). Both interventions

sub-stantially increased the amounts on nonfeeding time

that the parents spent holding or carrying their

ba-bies. This was due to highly significantly increases in

the amounts of carrying time while the babies were

settled, whereas the amount of carrying or holding

during crying did not differ between the groups.

Duncan’s multiple-range test showed that

carrying-intervention infants were carried significantly more

while settled than were both other groups at both

ages (P < .05), whereas responsiveness-intervention

infants were carried significantly more than control

infants at 2 weeks (P < .05) only. However, Table 2

shows that the figure for the

responsiveness-inter-vention group fell between the figures for the other

two groups at both ages.

Effects of the Interventions on Parental Interaction

and Responsiveness

Table 3 shows the parental behaviors targeted by

the responsiveness intervention (amount of playing/

talking; number and duration of feeding) and those

involving basic care (changing, bathing, and

dress-ing). Although infant feeding was recorded on the

diary as an infant behavior, it involves an interaction

between infant and caregiver. Taubman’s

recom-mendations encourage parents to use feeding on

de-mand and non-nutritive sucking as components of

responsive care, so that an increase in the frequency

or duration of feeding was expected.

At 2 weeks, parents spent 44 to 48 minutes per day

playing and talking with their infants, with virtually

no variation between the groups. By 6 weeks, the

amounts of time spent in such social stimulation

increased in all three groups to 71 to 86 minutes, still

without a significant group difference. As Table 3

shows, the groups also did not differ in the total

amount of time spent feeding, which lessened in all

three groups with age. However,

responsiveness-intervention infants at 6 weeks received

approxi-mately one more feeding per 24 hours than the other

groups, a statistically significant increase. The

feed-ing-frequency measures showed the same pattern at

2 weeks, but the groups did not differ significantly at this age.

The amount of time spent in basic infant care was

not targeted by the interventions and, as expected,

did not differ between the groups.

Infant Crying and Fussing Behavior

Following Hunziker and Barr,9 we combined the

diary measures of fussing and crying to produce a

totaled fussing/crying measure. In view of the

sub-ject attrition that occurred, particularly in the control

group, analyses were first run to detect whether

infants who left the study had particularly high, or

low, levels of fussing/crying. For these analyses,

separate mean 24-hour diary fussing/crying figures

were calculated for the groups of infants who

ne-mained throughout the study, who left the study

before the 6-week measurements, or who left the

study before the 12-week measurements. Analysis of

variance confirmed that these figures were not

sig-TABLE 2. Number of Minutes Infant s Were Held/Carri ed Per Day*

Nonintervention Carrying Intervention

Responsiveness Intervention

ANOVAt Be tween Groups

F

At 2 wk

Carrying while baby fussing/crying 43 ± 46 54 ± 65 54 ± 76 0.90 .41 Carrying while baby settled 73 ± 68 181 ± 101 112 ± 78 35.73 <.0001

Total carrying 117 ± 81 234 ± 104 166 ± 102

At 6 wk

Carrying while baby fussing/crying 47 ± 56 59 ± 58 52 ± 58 0.75 .47

Carrying while baby settled 83 ± 78 173 ± 120 113 ± 90 15.84 <.0001

Total carrying 131 ± 98 233 ± 129 165 ± 102

* Data are presented as mean ± SD.

t ANOVA, analysis of variance.

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At 2 wk

Social stimulation, mm 44 ±46.7 48 ± 43.9 45 ± 36.3 0.18 .83

Feeding duration, mm 252 ± 70 249 ± 74 262 ± 82 0.53 .59

No. of feedings 8.7 ± 2.6 8.6 ± 2.6 9.4 ± 3.1 1.22 .30

Care, mm 84 ± 41 86 ± 52.7 80 ± 51 0.29 .75

At 6 wk

Social stimulation, mm 77 ± 69.8 71 ± 56.9 86 ± 68.5 0.75 .47

Feeding duration, mm 218 ± 83 211 ± 65 231 ± 87 1.01 .36

No. of feedings 7.8 ± 2.5 7.3 ± 2.5 8.7 ± 2.6 3.68 .03

Care, mm 73 ± 32.5 76 ± 37.8 74 ± 34.7 0.18 .83

* Data are presented as mean ± SD.

Nonintervention Carrying Intervention

Responsiveness ANOVAt Between Groups Intervention

At 2wk

Diary, min/24 h 130 ± 72 119 ± 90 124 ± 85 0.37 .69

Crying Patterns Questionnaire, min/24 h I 15 ± I I I 109 ± I 13 125 ± 132 0.29 .75

Maternal distress rate 19% 19% 22%

Referral rate 9% 13% 9%

At 6wk

Audio Recording, min/24 h 145 ± 73 144 ± 80 167 ± 101 0.50 .61

Diary, min/24 h 129 ± 71 128 ± 75 122 ± 79 0.15 .86

Crying Patterns Questionnaire, min/24 h 172 ± 166 132 ± 137 128 ± 88 2.26 .11

Maternal distress rate 28% 27% 33%

Referral rate 14% 24% 10%

At 12 wk

Diary, min/24 h 98 ± 48 75 ±38 70 ± 53 4.76 .10

Crying Patterns Questionnaire, min/24 h I 14 ± 126 75 ± 76 90 ± 87 1 .93 .15

* Data are presented as mean ± SD or percentage.

TABLE 3. 24-Hour Amounts of Social Stimulation (Playing and Talking), Feeding, and Basic Care*

Nonintervention Carrying Responsiveness Intervention Intervention

ANOVAt Between Groups

F P

nificantly different at 2 or 6 weeks, with no more

than 14 minutes’ variation between any pair of

groups at either age.

Table 4 summarizes the effects of the interventions

on infant fussing/crying, whereas Fig I shows the

diary figures for the intervention and control

condi-tions in the present study in relation to those of

Hun.ziker and Barr.9 As Fig I illustrates, the pattern

of findings in the two studies is quite different.

Hun-ziker and Barr found a steady decrease in fussing/

crying over age in their carrying-intervention infants,

with an increase followed by a decrease in control

cases. In contrast, both the intervention and control

infants in the present study matched the 5- to 6-week

fussing/crying levels of Hunziker and Barr’s control

cases by 2 weeks, retained this level at 6 weeks, and

showed a uniform decline at 12 weeks.

As Table 4 confirms, the fussing/crying totals for

the intervention and control infants in the present

study did not differ significantly on diary or Crying

Pattern Questionnaire measures obtained at 2, 6, or

12 weeks, or on audio recording measures made at 6

weeks of age. The groups also did not differ in the

rates of maternal distress or referral to health

profes-sionals because of crying at 2 or 6 weeks of age. The

only consistent trend toward a group difference was

found at 12 weeks: the mean 24-hour totals of

fuss-ing/crying reported by mothers in the two

interven-tion groups for the diary and questionnaire measures

were some 25 minutes lower than those reported by

control-group mothers (Table 4). However, this

dif-ference was not statistically significant, while, by this

age, fussing/crying levels in all three groups of

in-fants had declined (Fig 1). At 6 weeks, the Crying

Pattern Questionnaire measures only showed a trend

toward lower fussing/crying levels in the

interven-lion groups.

In view of the apparent inconsistency between our

results and those reported by Hunziker and Barr,9 we

performed two subsidiary analyses to examine more

directly the link between carrying while settled and

infant fussing/crying. First, to provide a direct test of

the relation between these variables, correlations

were calculated at each age for the total sample of

infants. Second, to consider the possibility that only

high amounts of carrying while settled are effective

in reducing crying, we selected cases in which an

infant was carried while settled for at least I

stan-dard deviation above the mean level for this variable

in the carrying-intervention group. The selected

in-fants were then compared with the remaining infants

on measures of fussing/crying.

The results showed that the overall correlations

between carrying while settled and infant fussing/

crying were nonsignificant (r = -.07 and -.09 at 2 and

6 weeks, respectively). Using the “extreme group”

approach to the data, 13 mother-infant pains were

selected as having high values for measures of

car-TABLE 4. Amounts of Fussing/Crying in the Three Groups of Infants*

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130

-120 _t

110

z

>-C)

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Cl)

w

I.-z

-J

0

I-.

100

-I

. 41

90- \

80 --- --- A

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70

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-.-60

2 3 5 6

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12

140--Figure. Diary mean 24-hour fussing/ crying totals in the intervention and

control groups in the present study and in the report by Hunziker and Barr

(1986).

INFANT AGE (WEEKS)

Pr.unt Study: Carrying Int.rv.ntlon k--A

R..ponslv.n.u nt.rv.ntlon Control

S-,-. Hunzlk.r & Barr: Carrying lnt.rv.ntlon

Control

A- - -A #{149}- - -$

rying while settled at 2 weeks, and 9 pairs at 6 weeks,

the majority of whom (9 and 6, respectively), were in

the carrying-intervention group. In keeping with the

correlation findings, the amounts of fussing/crying

in the extreme carrying-while-settled cases did not

differ from those in the remaining infants (2 weeks

fussing/crying, F (1) = 0.60; P = .44; 6 weeks fussing/

crying, F (1) = 0.14; P = .71).

DISCUSSION

In this study, we set out to compare two methods

believed to be useful in reducing infant crying for

their effectiveness when used as primary

preven-tive interventions in a general community.

Moth-ers and babies were approached in the newborn

wards of three hospitals and assigned arbitrarily to

a nonintervention control group or to one of two

intervention groups (carrying intervention;

re-sponsiveness intervention). Most mothers asked to

carry out the interventions agreed to do so, and,

although some sample attribution occurred at

fol-low-up ages, the attrition was greatest in the

con-trol group. Amounts of infant crying in this group

were similar to those found in previous studies of

infants of this age in the general community,14’15

whereas infants who left the study did not differ in

amounts of crying from those who remained.

Therefore, the study appears not to have been

biased by sample attrition.

Following Hunziker and Barr,9 we used 24-hour

diaries kept by the mothers to monitor whether the

planned interventions were implemented. As

in-tended, the findings showed that mothers in the

carrying-intervention group carried their babies

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significantly more when settled than did mothers in

both other groups at both 2 and 6 weeks of infant

age. The levels of supplementary carrying were

similar to those found previously, while the total

amount of extra carrying by the

carrying-interven-tion group (1 hour and 57 minutes more than the

control group at 2 weeks; I hour and 42 minutes

more at 6 weeks) closely matched the equivalent

figure of 1 .8 hours reported by Hunziker and Barr.9

Mothers in the responsiveness-intervention group

also increased the amount they carried their babies

while settled, to a level in between the amounts in

the carrying-intervention and control groups. In

ad-dition, this group demonstrated an increased

fre-quency of feeding, equivalent to approximately one

additional feeding per day. However, the

respon-siveness intervention was unsuccessful in increasing

the amount of time the mothers spent playing and

interacting socially with their babies. Although the

reason for this is not known, it may reflect the

developmental limitations of infants at this age. At 2

weeks, mothers reported that they spent only 45

minutes per day stimulating their babies and,

al-though this increased to 70 to 80 minutes at 6 weeks,

it may be that the infant’s capacity for social

interac-tion at this early age limits the amount of stimulation

that is possible.

To examine the effectiveness of these

interven-tions in reducing infant crying and fussing, we

measured infant crying by 24-hour audio

record-ings, by diaries kept prospectively by the mothers,

and by maternal questionnaires. Contrary to

pre-vious research and to our expectations, the overall

finding was of little or no effect of increased

car-rying or feeding frequency upon infant crying or

its impact on mothers. More specifically, there

were no significant differences between the control

and intervention groups on audio recording

mea-sures of fussing/crying at 6 weeks or on diary or

questionnaire measures at 2, 6, or 12 weeks of age.

Further, subsidiary analyses confirmed the lack of

an overall correlation between carrying while

settled and infant fussing/crying, and infants who

were carried the most did not differ from other

infants generally in their amounts of fussing/

crying.

These puzzling findings clearly raise a number of

issues for future research. First, it is necessary to

account for the inconsistency between the present

findings and those of Taubman,’1”2 who reported

successful use of parental counseling in reducing

infant crying. One possibility is sampling differences

between the studies; Taubman used his counseling

intervention to treat cases selected for colic crying,

rather than as a preventive intervention as here.

Al-ternatively, procedural differences between the

stud-ies may be involved. Taubman’s most recent account

of his method’8 stresses that it involves a “problem

solving” program of monitoring and treatment,

which is tailored to individual cases, rather than

solely the published list of recommendations

fol-lowed in the present study. It is possible that a

then-apist-guided approach of this kind would prove

more successful. However, evidence is needed to

identify the specific aspects of parental behavior

changed by this method and to link these directly to

infant crying. At present, the lack of this information

and of evidence that Taubman’s methods’1’12”8 are

superior to a nonintervention control procedure are

important limitations.

A second issue is why supplementary carrying,

previously found to reduce infant fussing/crying in

normal infants beginning in the fourth week of age,9

failed to reduce infant fussing/crying here. The

stud-ies were similar in the amounts of extra carrying

given to the infants. One possibility is that the results

of the present study represent a nonreplication of the

earlier findings when applied to a general

commu-nity sample of normal infants. A second is that the

discrepancy is due to differences in study design,

sampling, and methods. A third possibility is that the

planned differences in the timing of the interventions

(at birth versus in the fourth week of age) may be

important to the effectiveness of the caregiving

changes, and that this difference is reflected in the

absence of an effect in this study and its presence in

the previous research.

However, the main finding of this study is that

the advice to increase carrying or to increase

pa-rental responsiveness soon after birth was

ineffec-tive in reducing later infant fussing/crying or in

preventing parental complaints about the crying.

Although the reasons for the differences with

pre-vious intervention studies remain speculative, the

clear implication of these results is that there is still

little evidence that this advice can be

recom-mended as an effective primary intervention to

prevent later crying problems. Because advice to

increase carrying is also no more effective than

parental education as a treatment for infants with

established colic,10 it seems likely that widely

ap-plicable approaches to successful prevention and

treatment of infant crying problems are neither

simple nor close at hand.

ACKNOWLEDGMENTS

This study was supported by Project Grant no. G882569N of the U.K. Medical Research Council.

Eric Hadley designed and constructed the audio recording equipment used in this research. Ian Plewis provided statistical advice. We are also grateful to the mothers and infants who participated and to the staff at Queen Charlotte’s and Chelsea Hospital, The Royal Free Hospital, and Whipps Cross Hospital.

REFERENCES

1. Frodi AM. Contribution of infant characteristics to child abuse. IN: Lester BM, Boukydis CFZ, eds. Infant Crying: Theoretical and Research

Perspectives. New York: Plenum; 1985:263-278

2. Forsyth BW, Leventhal JM, McCarthy PL. Mothers’ perceptions of problems of feeding and crying behavior. Am I Dis Child. 1985;139:

269-272

3. St. James-Roberts I, Halil T. Infant crying patterns in the first year:

normal community and clinical findings. I Child Psychol Psychiatry.

1991;32:951-968

4. St. James-Roberts I, Hurry J,Bowyer J. Objective confirmation of crying

durations in infants referred for excessive crying. Arch Dis Child. 1993; 68:82-84

5. Forsyth BWC, Canny PF. Perceptions of vulnerability 3#{189}years after

problems of feeding and crying behaviour in early infancy. Pediatrics.

1991;88:757-763

6. St. James-Roberts I. Managing infants who cry persistently. BMJ. 1992a; 304:997-998

(8)

7. Forsyth BWC. Colic and the effect of changing formulas: a double-blind, multiple-crossover study. IPediatr. 1989;1 15:521-526

8. Lothe L, Lindberg T. Cow’s milk whey protein elicits symptoms of

infantile colic in colicky formula fed infants: a double-blind crossover study. Pediatrics. 1989;83:262-266

9. Hunziker UA, Barr RG. Increased carrying reduces infant crying: a

randomized control trial. Pediatrics. 1986;77:641-648

10. Barr RG, McMullen SJ, Speiss H, et al. Carrying as colic “therapy”: a

randomised controlled trial. Pediatrics. 1991;87:623-630

11. Taubman B. Clinical trial of the treatment of colic by modification of parent-child interaction. Pediatrics. 1984;74:998-1003

12. Taubman B. Parental counselling compared with elimination of cow’s

milk or soy milk protein for the treatment of infant colic syndrome: a

randomised trial. Pediatrics. 1988;81 :756-761

13. McKenzie S. Troublesome crying in infants: the effect of advice to reduce stimulation. Arch Dis Child. 1991;66:1416-1420

14. Barr RG. The normal crying curve: what do we really know? Dev Med

Child Neurol. 1990;32:356-362

15. St. James-Roberts I. Persistent crying in infancy. IChild Psychol

Psychi-atry. 1989;30:189-195

16. Barr RG, Kramer MS. Boisjoly C, et al. Parental diary of infant cry and fuss behavior. Arch Dis Child. 1988;63:380-387

17. St. James-Roberts I. Measuring infant crying and its social perception and impact. Association for Child Psychology and Psychiatry Newsletter. 1992b;14:128-131

18. Taubman B. Treatment of Infant Colic Syndrome by changing parental responses. Paper presented at the IVth International Workshop on Infant Cry Research, Munich, July 12-15 1992

JUNK SCIENCE JUNKED

It took a decade, but in a California courtroom this month science finally beat the

plaintiffs’ lawyers. The Ninth Circuit Court of Appeals dismissed the notorious

Bendectin case.

This was the lawsuit brought by the parents of two children who said their sons’

birth defects were caused by the anti-morning sickness drug that the mothers took

during their pregnancies. The dismissal is a giant step toward returning sanity to

our out-of-control tort liability system.

In a unanimous opinion filed on January 4, a three-judge panel ruled that the

science offered up by the plaintiffs’ experts was inadequate. The court pointed out

that none of their findings had been published in scientific journals or offered up

for peer review.

The count didn’t mince words. “Bendectin litigation has been pending in the

courts for over a decade,” Judge Alex Kozinski’s scathing opinion reads, “yet the

only review the plaintiffs’ experts’ work has received has been by judges and juries,

and the only place their theories and studies have been published is in the pages

of federal and state reporters.”

Or as we would put it, the aim of this case wasn’t a search for truth and justice

but a search for deep pockets.

The Wall Street Journal. (Review & Outlook). January 19, 1995.

Noted by J.F.L., MD

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1995;95;381

Pediatrics

Ian St. James-Roberts, Jane Hurry, Josephine Bowyer and Ronald G. Barr

Interventions to Prevent Persistent Infant Crying