PEDIATRICS Vol. 99 No. 1 January 1997,
p. e6
Copyright ©1997 by the American Academy of Pediatrics
ELECTRONIC ARTICLE:
Determinants of Parental Authorization for Involvement of Newborn
Infants in Clinical Trials
John A. F. Zupancic*,
Pat Gillie*,
David L. Streiner
, §,
John L. Watts*, and
Barbara Schmidt*, §,
From the Departments of * Pediatrics,
Psychiatry, and
§ Clinical Epidemiology and Biostatistics, McMaster University,
Hamilton, Ontario, Canada.
ABSTRACT
INTRODUCTION
METHODS
RESULTS
DISCUSSION
FOOTNOTES
ACKNOWLEDGMENTS
ABBREVIATIONS
REFERENCES
ABSTRACT
Objective. Parents have the right to
decide on behalf of their infants whether to enroll them in controlled
clinical trials. We determined the degree to which such parental
decisions are influenced by risk and benefit considerations compared
with other factors.
Design. Cross-sectional survey.
Participants. Parents who had recently given or declined
consent to one of three controlled trials in the neonatal intensive care unit.
Intervention. Parents were asked to complete a
questionnaire that consisted of 15 sociodemographic items and 13 scaled
responses to statements assessing the probability and magnitude of risk and benefit as well as perceived illness severity, attitudes toward research, and the consent process.
Analysis. Responses were subjected to factor analysis to
identify underlying constructs. The sample was then randomly split, and
multiple regression was performed on each half.
Results. The response rate was 83% (103 of 124) for those
who had consented and 86% (37 of 43) for those who had declined. Factor analysis yielded three factors: (1) illness severity, (2) perceptions of risk or benefit and attitudes to research, and (3)
sociodemographic characteristics. Multiple linear regression showed a
significant multiple correlation of consent decision (r = .502), but only the second factor
contributed. The analyses on split halves of the sample were
comparable. Thirty-two percent of all parents agreed with the
statement, "I would prefer to have the doctors advise me whether my
baby should be in the study, rather than asking me to decide."
Conclusions. In making consent decisions on behalf of
their newborn infants, parents are influenced by risk and benefit
assessments, attitudes toward research, and the integrity of the
consent process. Illness severity or sociodemographic characteristics
do not seem to be of similar importance. Rather than making the
decision alone, a significant minority of parents would prefer to have
the physicians advise them whether to volunteer their infants for a
clinical trial. medical ethics, informed consent, newborn
infant, clinical trial.
INTRODUCTION
In 1964, the World Medical Association recommended in its
Declaration of Helsinki that informed consent be obtained from all human subjects before their involvement in biomedical
research.1 The acceptance of the doctrine of informed
consent has accompanied an important shift from paternalism in clinical
medicine to patient autonomy.2,3 Legal precedents and
reports of research excesses led to political regulation of consent for
clinical research along similar lines to consent for therapeutic
procedures.3,4 However, one assumption underlying the
principle of autonomy
that a competent person who understands
disclosed information decides to give or to refuse consent after
considering potential risks and benefits
remains more or less
untested.5,6
A paucity of empirical data is particularly evident for parental
authorization of neonatal research involvement. Despite the intense
clinical research activity in many neonatal intensive care units
(NICUs), few, if any, studies have so far examined the process of proxy
consent for the newborn. An exploration of this process is particularly
important, because decisions on behalf of children are expected to be
made in their best interests. This implies that parents have less
latitude to be as idiosyncratic or unconventional as they may be in
making decisions for themselves. Instead, they have a greater
responsibility to weigh risks and benefits.
The present study was designed to determine the degree to which
parental authorization of neonatal involvement in clinical trials is
influenced by risk and benefit considerations compared with other
factors such as the infant's severity of illness at the time of the
consent decision or parental sociodemographic characteristics and
attitudes to research and the consent process.
METHODS
Instruments
A 29-item questionnaire was developed specifically for the
study. The instrument included four items in which the parents were
asked to estimate the probability as well as the magnitude of benefit
and harm that they expected for their infants from participation in the
"feeder" trial. Responses were entered on a seven-point Likert
scale, anchored at "definitely would not" (benefit or be harmed)
and "definitely would" (benefit or be harmed). Nine additional
questions assessed factors that have been suggested to affect consent
rate; these included a parental rating of illness severity, perceived
coercion, and perceived complexity of the consent process, as well as
altruism, the desire to delegate decision making to physicians, and
general attitudes toward research. For each, the parents were asked to
what extent they agreed or disagreed with the statement, again using a
seven-point scale. One open-ended question, used to check content
validity, asked for the single most important reason for the parental
decision. The remainder of the questionnaire assessed sociodemographic
factors.
The instrument was pretested for readability and comprehensibility on a
sample of 10 parents in the NICU who were not included in the main
study. Face validity was good, and any misunderstood or ambiguous items
were rewritten. All responses to the open-ended question were addressed
by one of the scaled items.
The first 10 parents enrolled were asked to complete the questionnaire
again 2 weeks after their initial response. The intraclass correlation
coefficients for the individual scaled responses ranged from
r = .77 to .97, indicating very good test-retest
reliability. The response distribution on scaled questions was good,
with frequency of endorsement for at least three of seven response
alternatives of greater than 5% on all items.
Objective scores for illness severity were assigned using the
previously validated Score for Neonatal Acute Physiology
(SNAP).7 The SNAP was calculated for the calendar day on
which the parents had been approached for consent to one of the three
feeder trials. The Hollingshead index of social status8 was
calculated to condense sociodemographic information.
Study Population and Setting
The study took place in the NICU at McMaster University Medical
Centre from February 1993 to March 1995. This 33-bed tertiary referral
unit serves a regional population of 1.8 million people. Approximately
1000 neonates are admitted annually, of whom 80% are born in the
center; the remainder are referred from surrounding hospitals.
The subjects were parents who had recently been approached for consent
to enroll their newborn infants in one of three independently funded
randomized, controlled trials taking place concurrently in the NICU.
The first of these was a multicenter controlled trial of the effect of
vitamin C supplementation on hemolysis. It involved stable, premature
infants with birth weights 1000 to 1500 g who were enrolled
between days 2 and 5 of life. Infants received a study medication such
that their total vitamin C intake was equivalent to the low amount
found in breast milk or to the high amount that is contained in some
commercially available formulas. The intervention continued for 14 days, during which three small blood samples were drawn at the time of
routine blood work. The second study was a placebo-controlled trial of
the protease inhibitor antithrombin. Participants were mechanically
ventilated infants with birth weights of 750 to 1900 g who had
respiratory distress syndrome. Infants were enrolled in the first few
hours after birth and remained in the trial for 48 hours, during which
several small blood samples were drawn from an indwelling catheter. The
third investigation was a randomized comparison of continuous infusion
to maintain the patency of intravenous lines with a saline lock device
in stable infants of any birth weight who needed intravenous access only for medications. No additional testing was required.
Informed consent for each of the three trials was obtained by a variety
of staff, including a research nurse, neonatal fellows, and
neonatologists. In each case, parents received a one-page information
sheet, which summarized the objective and design of the trial.
Maneuver
Shortly after authorizing or declining enrollment of their
infants in one of the trials, parents were informed by letter of the
questionnaire study. They were then approached by a research nurse a
few days after the initial consent decision; this timing represented a
compromise between further interference with the parents at a time of
stress and the need to assess attitudes as closely as possible to the
actual consent decision. The purpose of the study was again outlined,
and a copy of the confidential questionnaire was given to the parents
to be returned in a sealed envelope. Assistance with any reading
difficulties was offered, but no parents availed themselves of this
opportunity. In contrast to some consent discussions at entry into a
feeder trial, interpreter services were not offered for completion of
the questionnaire.
The option to decline participation or to leave some questions
unanswered was emphasized. The study was approved by the Research Advisory Group at McMaster University.
Data Analysis
Responses and data for SNAP scores were entered into a
spreadsheet program. SNAP scores were calculated using the Excel 4.0 computer program (Microsoft Corp, Redmond, WA, 1992), and statistical analysis of questionnaire responses was completed with the Statview 4.1 computer program (Abacus Concepts, Inc, Berkeley, CA, 1994). All scaled
responses were treated as interval data.9 Responses were
subjected to factor analysis, using principal components analysis and
varimax rotation. Three factors were retained using Cattell's Scree
test. This reduction in the number of variables allowed the original
sample to be randomly split; the first half was used to generate a
multiple regression model, and validation of the model was performed on
the second half. Demographic data not included in this analysis were
compared using Student's t test and the
2
test for continuous and nominal data, respectively.
RESULTS
Study Participants
During the study period, the parents of 186 patients were asked
for permission to enroll their infants in one of the three feeder
trials (vitamin C, n = 12; antithrombin, n = 96; and saline lock, n = 78). Consent rates were 42% for the vitamin C study, 80% for the antithrombin trial, and 76% for the saline lock study. One hundred sixty-seven sets of parents were approached for
participation in the questionnaire study. Of the 19 families excluded,
3 had limited English skills, 5 were not approached for compassionate reasons, 6 could not be contacted in due time, and in 5 pairs of twins
the questionnaire was requested only for the second twin, according to
study protocol. Of the 167 sets of parents who received the
questionnaire, 140 (84%) responded. Among parents who consented to a
feeder trial, 103 (83%) of 124 responded, compared with 37 (86%) of
43 parents who did not consent to a feeder trial.
Sociodemographic Data
Infant characteristics and family sociodemographic data are given
in Tables 1 and 2, respectively. There
were no significant differences between consenters and nonconsenters
for any of these variables.
Parental Responses to Scaled Items
Responses to the 13 scaled items are shown in Figs through 4. The differences between consenters and nonconsenters were most marked
for estimates of risks and benefits (Fig 1). In
contrast, parental perceptions of illness severity were similar between consenters and nonconsenters (Fig 2). Ninety-four
percent of all parents (98% of consenters and 84% of nonconsenters)
endorsed altruistic motives as important considerations in making the
decision (Fig 3). Thirteen percent of parents (10% of
consenters and 22% of nonconsenters) agreed or strongly agreed that
the process was too complex, whereas only 3% (3% of consenters and
6% of nonconsenters) reported feeling pressure to consent. Four
percent of parents were concerned that there might be reprisals for not
participating in a trial (Fig 4).
Fig. 1.
Parental responses to risk and benefit items. Shaded areas correspond
to the percentage of parents endorsing each box on the seven-point
Likert scale. c indicates consenters; and n, nonconsenters. *"Do
you think it is likely that your baby might benefit from being in the
study?"
"If you think your baby would benefit, how great would
the benefit be?"
"Do you think it is likely that your baby might
be harmed by being in the study?" §"If you think your baby would
be harmed, how great would the harm be?"
[View Larger Version of this Image (50K GIF file)]
Fig. 2.
Parental perception of illness severity. Shaded areas correspond to the
percentage of parents endorsing each box on the seven-point Likert
scale. c indicates consenters; and n, nonconsenters. §"How ill was
your child at the time you were asked to participate in the study?"
[View Larger Version of this Image (21K GIF file)]
Fig. 3.
Parental attitudes to research and the consent process. Shaded areas
correspond to the percentage of parents endorsing each box on the
seven-point Likert scale. c indicates consenters; and n, nonconsenters.
*"It is important for children to take part in research because what
doctors learn may help other children."
"Babies who take part in
research are receiving the best care possible."
"Neonatal units
where research takes place provide better care to babies than units
where there is no research." §"I would prefer to have the doctors
advise me whether my baby should be in the study, rather than asking me
to decide."
[View Larger Version of this Image (44K GIF file)]
Fig. 4.
Parental attitudes to research and the consent process. Shaded areas
correspond to the percentage of parents endorsing each box on the
seven-point Likert scale. c indicates consenters; and n, nonconsenters.
*"I felt completely free to decide whether my baby should take
part."
"The way in which I was asked for permission was too
complicated."
"I was concerned that if I said `No' the staff
would be less interested in caring for my baby." §"It is important
to take part in research to show gratitude for care my baby has
received."
[View Larger Version of this Image (40K GIF file)]
Thirty-two percent of parents (33% of consenters and 30% of
nonconsenters) agreed or strongly agreed with the statement, "I would
prefer to have the doctors advise me whether my baby should be in the
study, rather than asking me to decide" (Fig 3).
Factor Analysis and Regression Model
Factor analysis yielded three factors. The first corresponded to
"illness severity" and comprised birth weight, SNAP, and parental
rating of illness severity. The second factor, "risk, benefit, and
attitudes," included the probability and magnitude of risk and
benefit, altruism, general attitude to research, perceived complexity
of decisions, freedom to make decisions, and concerns about reprisal.
Items loading on the third factor, "sociodemographics," included
parental age and the Hollingshead index of social status.8
Multiple linear regression showed a significant multiple correlation of
consent decision (r = .502; P < .0001), but only factor 2, risk, benefit, and attitudes, contributed.
The analyses on split halves of the sample were comparable (sample 1, r = .577; P < .0001; sample 2, r = .438; P = .0015). There was no
correlation between the desire to have physicians advise on the consent
decision, other attitudes to research, the estimate of risk and
benefit, illness severity, or sociodemographic variables
(r = .176; P = .2319).
DISCUSSION
In this study, authorization of neonatal involvement in controlled
clinical trials was correlated with lower parental estimates of risk
and higher estimates of benefit. Consenting parents were also more
likely to report altruistic motivation, freedom to make the decision
independently, and positive attitudes toward research and the consent
process. Sociodemographic characteristics and the infant's severity of
illness at the time of the consent decision seemed of lesser
importance.
This study is the first to correlate the determinants of parental
decision making for the involvement of newborn infants in clinical
trials with the direction of the consent decision and the first to test
the assumption that parents weigh risks and benefits of a proposed
research protocol. Several limitations of previous studies in older
children and adults have been avoided.5 The instrument was
pretested and had good reliability, face validity, and response
distribution. Real rather than hypothetical consent decisions were
examined, thus ensuring that the emotional influences associated with
the stress of personal involvement would be assessed. Parents who
consented were compared with those who refused, allowing a meaningful
control for trends in responses. The response rate was good, even among
parents who had refused participation in the feeder study.
Generalizability was enhanced by the sampling of parents involved in
consent decisions for three trials with very different risks and
inclusion criteria.
Concern has been expressed that, among those consenting to research
involvement, there may be a disproportionate representation of
individuals who are unable to understand the information or who, by
virtue of social disadvantage, are too intimidated to refuse.3 Our results are reassuring. Parents who consented showed no differences in education or social class index. More importantly, parents who reported less freedom to make the decision and
who thought that the consent process was too complicated were actually
less likely to permit involvement of their children in a clinical
trial. It is possible that the parents who are most vulnerable to
deficits in the integrity of the research process may recognize this
and may decline any involvement. In contrast, consenting parents in an
Australian trial of a drug to treat asthma had a lower level of
postsecondary education and professional occupation than parents who
had not volunteered their children for this trial.10
One third of the parents in this study agreed or strongly agreed with
the statement, "I would prefer to have the doctors advise me whether
my baby should be in the study, rather than asking me to decide." In
the Australian survey of parents who volunteered their children for a
trial of a new asthma drug, 15% of the parents were of the opinion
that the informed consent procedure was unnecessary because of their
faith in their physicians' advice.11 Attempts to define
this group of parents further in our study with respect to direction of
consent, attitudes, sociodemographic factors, risk and benefit
considerations, or illness severity showed no differences from those
who would prefer to make the decision themselves.
Because genuine respect for parental autonomy would require that
families be allowed the option to solicit their physician's advice
before making a consent decision, future research is needed to confirm
our findings and to explore the feasibility of more individualized
consent policies, which do justice to the different levels of
independence that parents may desire.
Several limitations of the present study must be acknowledged. Any
questionnaire-based evaluation is only an approximation of actual
motivations. The validity of the responses will also be affected by the
time lag between the decision and questionnaire completion, because
parents' interpretation of risks may be altered by the infant's
subsequent course, and their attitudes may be affected by later
experiences in the NICU. We did not find it acceptable to approach
parents immediately after the consent decision. The proven reliability
of the questionnaire may provide some reassurance that experiences in
the NICU did not change the responses substantially.
Although the study population is fairly typical for a Canadian
tertiary-level NICU, the proportion of socially disadvantaged parents
may be much higher in other countries. This may affect the conclusions
regarding sociodemographic influences on consent, because we would be
less likely to detect these in our more homogeneous population.
Similarly, the power of the study to detect influences of illness
severity or sociodemographic factors on the consent decision may have
been weakened by the smaller numbers of nonconsenters compared with
consenters. Moreover, we were not able to determine the relative
priority of parental weighing of risks and benefits and their attitudes
to research, because both loaded onto the same factor in the analysis.
Separation of the two would require a much larger sample. Finally,
psychologic profiles of the parents were not determined. Parental
anxiety has been correlated with consent for research involvement of
asthmatic children in Australia.12
Despite these caveats, we conclude that parents approached for
permission to enroll their infants in clinical trials do seem to weigh
risks and benefits, and those who are most uncomfortable with the
informed consent process are least likely to consent.
Future research should attempt to test in a controlled fashion methods
of obtaining authorization, which would increase the degree to which
parents use risk and benefit considerations, and decrease further the
perceptions of complexity and coercion.
FOOTNOTES
A Career Investigator of the Heart and Stroke Foundation
(Ontario, Canada).
Received for publication Mar 27, 1996; accepted Jul 24, 1996.
Presented at the Annual Meeting of the Society for Pediatric
Research, San Diego, CA, 1995, and at the Annual Meeting of the Royal
College of Physicians and Surgeons of Canada, Montreal, Quebec, Canada,
1995.
Reprint requests to (B.S.) Department of Pediatrics, McMaster
University, 1200 Main St W, Hamilton, Ontario, Canada L8N 3Z5.
ACKNOWLEDGMENTS
This work was supported by a resident research award (Dr
Zupancic) from the Physician's Services Inc Foundation (Toronto, Ontario, Canada).
We are grateful to the parents who completed the questionnaires and
thereby made this work possible.
ABBREVIATIONS
NICU, neonatal intensive care unit.
SNAP, Score for
Neonatal Acute Physiology.
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