Clinical Trial Details
— Status: Recruiting
Administrative data
| NCT number |
NCT03960047 |
| Other study ID # |
1R21HD093878-01A1 |
| Secondary ID |
|
| Status |
Recruiting |
| Phase |
Phase 2
|
| First received |
|
| Last updated |
|
| Start date |
April 1, 2019 |
| Est. completion date |
June 1, 2021 |
Study information
| Verified date |
May 2019 |
| Source |
University of Guelph |
| Contact |
Barbara Morrongiello, PhD |
| Phone |
519-824-4120 |
| Email |
bmorrong[@]uoguelph.ca |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Motor vehicle pedestrian injury is a critical issue for school children.1-4 Each year in the
US, over 4900 pedestrians are killed and another 207,000 are injured, and about 25% of these
pedestrian events involve school-age children. This research focuses on 7-8 year olds, who
constitute a high-risk group for pedestrian injury. At these ages children regularly cross
streets without supervision and they struggle both with selecting where to cross and
determining how to cross. Research has shown, however, that children are capable of
benefiting from effective behavioral training in pedestrian behavior. The proposed research
addresses the issue of crossing skills deficits and will: (1) implement a randomized
controlled trial (RCT) to test two alternative training programs to teach 7-8 year-olds where
and how to cross streets safely; and (2) conduct an economic analysis to reveal cost:benefit
indices for both.
Meta-analyses of pedestrian training programs reveal that behavioral training in a traffic
environment most reliably produces some degree of improvement in crossing skills. Thus,
'street-side training' is often described as the gold standard. Implementation, however,
poses many practical problems related to implementation. The investigators have addressed
this issue by developing a training system that uses a virtual pedestrian environment and
extends past VR systems by having children fully cross the street and offering the unique
capability of teaching both where and how to cross, with skills in each domain measured
separately so exactly what is learned and what component crossing behaviors improved can be
precisely determined for each individual child.
Children (7-8 years) will be randomized to one of three groups (balanced for sex):
street-side training, virtual-reality training, and a no-intervention control, with the same
pre- and post- measures taken across groups. Primary analyses will test for changes in
indices of where and how to cross, as well as attention to traffic when crossing. An economic
analysis of the two programs will reveal their relative cost effectiveness. These results
will provide essential knowledge to inform future decisions about 'best practices' in child
pedestrian injury prevention through behavioral training.
Description:
APPROACH
1. RESEARCH GOALS. The specific goals are: (1) conduct a RCT with 7-8 year olds to evaluate
the relative effectiveness of 2 training programs (Virtual Reality, Street Side),
compared to a no-intervention control, with a focus in training on where and how to
cross. (2) Conduct an economic analysis of the programs to ascertain their relative cost
effectiveness. These results will provide essential knowledge on relative program
effectiveness and economic costs to inform future decisions about 'best practices' in
child pedestrian injury prevention through behavioral training
2. STUDY DESIGN: 3 Groups Recruited children will receive the pre-tests and then be
randomly assigned to one of three groups (2 Intervention, 1 Control), using a block
(sex) randomization procedure so Intervention groups (VR training or VR-T, Street Side
training or SS-T) and the no intervention Control group (No Intervention: NI-C) are
balanced for sex of the child.
3. RESEARCH QUESTIONS Does performance in VR-T exceed that in NI-C? Does performance in
SS-T exceed that in NI-C? Is performance equivalent in VR-T vs SS-T or does one produce
better outcomes and qualify as best practice? Do any immediate gains persist over time
(2 months post-intervention)? What is the cost-effectiveness of VR-T compared to SS-T?
4. POWER ANALYSIS All calculations were performed by a consulting statistician (Dr. Gerarda
Darlington) using a function written in R version 3.3.2 based on a formula provided by
Julious and using the pwr.anova.test function from the pwr package in R. Results from
the pilot feasibility study were used to estimate mean changes for where and how to
cross: after VR-T, children crossed in unsafe locations 65% fewer times and there was a
68% increase in how to cross safely, with both variables being normally distributed.
With a within-group standard deviation of 0.16 (pilot data) and a sample size of 58
children per group, we would have over 80% power to confirm equivalence between the VR-T
and SS-T groups, assuming no observed difference in change scores between the groups and
an equivalence threshold level of 17%, with alpha=0.025. Note that the total sample size
would support the analyses planned, allowing for significance at p < 0.0001 with power
greater than 95%. Allowing for 10% attrition, we will recruit 64/group (N = 192).
5. SUBJECT POPULATION AND ELIGIBILITY CRITERIA [*see Introduction to Application please] A
total of 192 children 7-8 years will be recruited, with 64 assigned to each group; this
includes allowance for 10% attrition (usual rate=5%). Youth will be randomly sampled
from an existing database of 9250 community recruited volunteers, with supplemental
recruiting (as needed) through community organizations and advertising. Use of the
database increases the speed and efficiency with which we can execute the research but
does not change the base population-it is all a community recruited sample. Inclusion
Criteria: developing normally (parent report; no learning, social, physical, mental
health concerns), English speaking. Exclusion Criteria: self or anyone in family
hospitalized for injury as a pedestrian, which can lead to atypical cautiousness.
6. RANDOMIZATION Blinding. Blinding to condition is not possible but greater bias may be
introduced in RCTs through inadequate allocation concealment than with blinding. All
participants will be blind to the study hypotheses.
Allocation of participants will occur by via a computer-generated random number
sequence.
7. TIMING OF EVENTS AND MEASURES All children do an initial visit to complete the pre-test
measures and are then randomized. Then SS-T and VR-T children complete 6 weekly training
sessions (~30 minutes/session). All children then complete another visit for post-test
immediate measures, with a longer-term visit (2 months later) to evaluate sustainability
of any improvements.
8. SETTING Midblock crossing on two-lane bidirectional roads, without nearby traffic
signals or crosswalks, are the focus.
For SS-T sessions, a road has been identified (50 km limit) that provides opportunity
for training in where and how to cross in the same types of road situations to be
presented in VR-T. Traffic volume was recently measured for 7 days and varied from light
(8 cars/min) to heavy (16 cars/min). This range for traffic volume will occur in VR-T.
For VR-T sessions, these occur in the VR lab at UG campus. For pre and post measures,
for all groups these occur in two settings: (a) street side (designated as "Field"
below) with naturally varying traffic (children indicate where and how they will cross
but do not do so), (b) in the VR lab in which children cross the virtual street in
traffic using a gaming controller.
Note that the pre/post Field measures will be taken at two locations along the same road
(randomized order, with one used for pre and the other for post), which controls for
familiarity and minimizes risk of large variation in traffic volume between pre/post
measures. The road is nearby the VR lab, which allows children to complete pre-test VR
and Field measures during the same visit to UG; the same will occur for post-test
measures. Posted speed is 50 km, which means traffic conditions to be tested on are ones
that pose risk of severe injury at these ages.
9. TESTING PROTOCOL Pre/Post measures for Where and How to Cross [Note that pre- and post-
measures are the same, and all children, regardless of group, complete all measures.
***Reliability for coding street side crossing will be completed.] Field Measures. For
where to cross measures, the child selects the safest location to cross in 3 different
street side situations (parked cars, hill, blind curve). For how to cross measures: the
child stands 1 foot from the curb, with a pressure sensitive step plate in front of him
(it connects to a laptop; a clear plastic wall prevents entry into the street), and
completes a '2 step procedure' (based on observed traffic, take 2 steps forward,
corresponding to initiating a street crossing; from this we estimate crossing
measures.[NOTE: Street side testing is video recorded so traffic and crossing measures
and reliability can be computed later.] VR Measures. The same measures as for Field,
except completed within a virtual street environment.
Pre-Training Activities & Measures VR-T. An initial Orientation and Movement-Control
Training Module ensures all children are practiced with using the controller to navigate
in the 3-D world to the same motor skill level, before starting pedestrian training. The
controller allows them to vary their path, direction, and speed of walking and crossing.
SS-T. Children's average walking speed for crossing is determined and then, in
combination with video taken street side, is used to estimate crossing measures - so
they do not cross in traffic, but only give initiation judgements. This is a common
approach that has been used before.
Training Programs [All program decisions were informed by pilot testing.] Each includes
6 training sessions of 30 minutes (2% of our pilot sample needed a break) and addresses
where and how to look and cross. Performance is tracked on a trial-by-trial basis, and
errors result in repetition of teaching trials, resulting in more training on skills
they lack than those they have. Difficulty level generally increases over sessions as
children acquire skills.
VR-T. Children experience trials from each of three training modules that are organized
logically for how one crosses: (1) deciding where to cross (component skills: identify a
safe place with parked cars, traffic on hills, traffic on blind curves); (2) effective
looking (component skills: left-right-left, always left as one enters the road); (3) how
to cross safely (component skills: check traffic in both directions, select larger gaps,
start right in when car back bumper passes). On each trial, the computer talks and
provides immediate feedback on performance so children know if they safely completed the
trial (e.g., "Great job") or what they did that was unsafe and why (replays of what the
child did are shown and explained), and what to do instead. A component skill is tested
(with explanatory feedback given for failures) until the child achieves at least 80%
success over a minimum of 5 trials or completes 10 trials. The child then moves on to
test another skill, with failed component skills retested in a future session. Over
sessions, the child gets repeated training on all modules and skills, but repetition
focuses mostly on skills the child still needs to achieve.
SS-T. The Kerbcraft program is grounded in behavior theory (modeling, reinforcement).
The program includes where and how content and is organized similarly to VR-T (modules,
teach component skills, immediate feedback). Over sessions, children get training on all
modules and skills, with repetition focusing on weaker skills. Testers (RA, students)
will follow a detailed manual that outlines program delivery.
10. PRIMARY OUTCOME MEASURES Behavior Measures. [All have been used in prior research.] Pre
and Post measures are taken in two settings (VR lab and Field street side). In each
setting, children complete 15 where trials (they indicate where to cross, but do not do
so) and 15 how trials (they decide about crossing in traffic).
Where. One score: average proportion of 15 trials the child chose the safe option for when
crossing on a hill (5 trials), with blind curves (5 trials), with parked cars (5 trials).
These 3 component scores will also be analysed separately (see Secondary Analyses).
How. Three scores: (1) Attention composite (proportion of 15 trials they looked correctly:
L/R/L, always L just before they step into road for VR-T or would have for SS-T); (2) Start
Delay (time in seconds between rear bumper of car passing and beginning of starting across);
(3) Inter-vehicle Temporal Gap Size selected (in sec).
Consequence. Two scores (from how trials): (1) average Time Left to Spare (i.e., how close
the car came in seconds); (2) composite of proportion of Near Miss (car passed within 1 sec
of child) and Hit trials.
Economic Measures The key outcome is hits, as this would result in economic burden of injury.
First, the actual cost of implementing the two training programs (personnel, equipment, etc.)
will be determined. Then a decision analytic model will be developed to compare each program
to the no-intervention group. The model will take a societal perspective, including both
government payer (direct hospital and non-hospital costs: ER visits, community physician
visits, etc.) and individual/ family out of pocket costs (e.g., out of hospital drugs, home
care services, lost productivity). A lifetime time horizon will be used, noting that some
injuries are severe and will have a long-term impact on morbidity and quality of life.
Probabilistic sensitivity analysis will assess the robustness of the model. Cost data will be
captured from relevant administrative databases; where data are missing, relevant literature
and/or expert opinion will be used to estimate costs.
