Using the Change Model to Interpret Variations in PTP Results

Transcription

Tomasz Sawicki
Eleni Harlan
Tony Duckenfield
Steer Davies Gleave
1
Contents
1
ABSTRACT.................................................................................................................... 3
Findings and Originality.................................................................................................. 3
Conclusions and Policy Implications .............................................................................. 3
Keywords ....................................................................................................................... 3
2
INTRODUCTION ........................................................................................................... 4
What is PTP? ................................................................................................................. 4
Engaging Thurrock ......................................................................................................... 4
Demographic Profiling .................................................................................................... 6
Benefits and Challenges ................................................................................................ 8
Measuring Sustained Change ........................................................................................ 8
3
METHOD ..................................................................................................................... 10
The Change Model ...................................................................................................... 10
4
RESULTS .................................................................................................................... 12
Contacts ...................................................................................................................... 12
Follow-up ..................................................................................................................... 13
Sustained Change ....................................................................................................... 14
5
ANALYSIS ................................................................................................................... 21
Implementation Analysis .............................................................................................. 21
Sustained Change Analysis ......................................................................................... 21
6
CONCLUSIONS........................................................................................................... 22
Notes ............................................................................................................................... 23
Figure 1: Thurrock Personal Travel Planning Project Areas 2012-14 .................................... 5
Figure 2:Typical Traits of Smarter TravelStyle Segments ...................................................... 6
Figure 3: Thurrock Smarter TravelStyle Analysis................................................................... 7
Figure 4: Thurrock Indices of Multiple Deprivation ................................................................. 9
Figure 5: The Change Model and Personal Travel Planning Outcomes............................... 11
Figure 6: Path of Analysis ................................................................................................... 12
Figure 7: Aggregated Results for Thurrock Personalised Journey Planning ........................ 16
Figure 8: Cycle of Change - Contact Phase ........................................................................ 17
Figure 9: Cycle of Change - Follow-up Phase ..................................................................... 18
Figure 10: Cycle of Change - Sustained Change: Maintenance .......................................... 19
Figure 11: Cycle of Change – Sustained Change: Action ..................................................... 20
2
1
ABSTRACT
Personal Travel Planning (PTP) aims to shift peoples travel habits to more
sustainable modes by providing tailored information, motivation and resources to
individuals.
Travel Thurrock PTP is unique in terms of the length and coverage of its intervention.
As one of the largest PTP programmes funded by the DfT, it has been delivered to
the majority of borough residents (over 126,000). The scale and success of the
project has provided an opportunity to:


Assess the impact of the scheme over an extended time frame (to evidence
sustained behaviour change); and
Assess how results have varied between different areas of the borough.
Findings and Originality
While headline results include a 27% increase in walking trips, a 9% decrease in car
drive alone trips and a 19% increase in bus mode share, there were significant
differences in impacts between the years and areas targeted.
In order to examine the differences between Thurrock’s contrasting areas and how
these have impacted the scheme, the results from the Travel Thurrock project are
compared between each location. In addition, results are compared across these
periods of elapsed time: 3, 18 and 30 months.
Results from the monitoring surveys indicate that the levels of sustained change
remained high. The decay rate of effects of the project “wearing-off” was
approximately 10%, per annum with most of this effect felt within the first few
months.
The results from the Travel Thurrock project and the sustained change survey are
presented in relation to the cycle of change model of behaviour change. The model is
used to tell the story of the journey participants have taken, the changes they have
made and identify barriers which still remain.
Conclusions and Policy Implications
The paper will show how participation, behaviour change and levels of sustained
change varied based on factors such as access to and quality of local transport
services, indices of deprivation, and demographics.
In term of the sustained change, the Department for Transport’s value for money
assessment of Local Sustainable Transport Packages currently assume the decay
rate of Smarter Choices measures to be 33% per year3. In this context, findings from
Travel Thurrock indicate that Personalised Travel Planning measures deliver better
value for money than previously thought.
Keywords
Change Model, demographics, geography, monitoring, Smarter Choices, Smarter
TravelStyle, sustained change.
3
2
INTRODUCTION
Travel Thurrock Personalised Travel Planning
In July 2011, Thurrock Borough Council was successfully awarded the full £5m
funding they bid for from the Department for Transport’s Local Sustainable Transport
Fund. The bid detailed a package of Smarter Choices interventions to be
implemented in Thurrock over a four year period. Within the budget, Personal Travel
Planning (PTP) was included to be delivered to over half of Thurrock residents over
the course of the funding period. PTP would also be offered to workplaces through
Thurrock’s Workplace Travel Planning work stream which ran in parallel to the PTP.
The aim of the PTP programme was to encourage participating residents to consider
travelling more sustainably, by either reducing their car driver trips, or increasing use
of sustainable modes of travel such as public transport, walking, cycling or car
sharing.
What is PTP?
Personal Travel Planning (PTP), also known as Personalised Journey Planning
(PJP) is defined by the Department for Transport as "a technique that delivers
information, incentives and motivation to individuals to help them voluntarily make
sustainable travel choices. It seeks to overcome habitual use of the car, enabling
more journeys to be made on foot, by bike, bus, train or in shared cars."
PTP involves a conversation between a Travel Advisor and a local resident, usually
on the doorstep. During the conversation, the Travel Advisor will seek to establish
current travel patterns and frustrations with these. Using Motivational Interviewing 2
techniques (adapted by Steer Davies Gleave from the health sector), Travel Advisors
help residents identify and suggest alternatives that they could use to taking the car,
and offer suitable resources such as maps or information leaflets which may help the
resident try their new solution. These are then hand-delivered to the resident at a
later date.
Engaging Thurrock
Figure 1 shows the areas that were targeted over the three years of engagement:



In 2012 the intervention focused on Grays and Chadwell St. Mary;
In 2013 the intervention focused on Aveley, Chafford Hundred, South
Ockendon, South Stifford and West Thurrock; and
During 2014 the areas targeted included Tilbury, East Tilbury, Linford, Orsett,
Corringham and Stanford-Le-Hope.
.
4
Figure 1: Thurrock Personal Travel Planning Project Areas 2012-14
5
Demographic Profiling
Preparation for the project began by profiling the households in the target area using
Steer Davies Gleave’s Smarter TravelStyle geodemographic profiling tool. Profiling is
based on demographic and lifestyle characteristics of each household within the
target area combined with intervention outcomes collected by Steer Davies Gleave.
Smarter TravelStyle analysis was used to tailor delivery to best suit the
characteristics of the people living in each target area.
Smarter TravelStyle is based on the Mosaic system which has been developed by
Experian the UK’s largest owner of consumer data together with our own data on
travel behaviour and impacts of Smarter Choices interventions. There are nine
segments within Smarter TravelStyle each with its own characteristics, attitudes, and
propensity to respond to different measures and policies. An overview of key
demographic traits for each segment is provided in Figure 3.
Figure 2:Typical Traits of Smarter TravelStyle Segments
The map in Figure 3 shows the different TravelStyle types across the borough. As
can be seen, large proportions of the area are made up of Suburban Families and
Traditional Value segment types which tend to respond well to Personalised Travel
Planning. In contrast to this, significant pockets within the target area are from less
responsive segments including Urban Challenge and State Support. These typically
yield less than favourable outcomes and are more difficult to engage with, in part
because of financial constraints and lower levels of employment, and also because
these groups tend to already have high levels of bus use.
6
Figure 3: Thurrock Smarter TravelStyle Analysis
7
Benefits and Challenges
Thurrock PTP is unique in terms of both the scope and duration of the intervention
bringing with it specific challenges and benefits. Challenges have included the wide
ranging socio-demographic groups within the Borough meaning that interventions
have needed to be tailored to the people the project has been trying to engage. In
addition to varying demographics, access to good quality, reliable public transport
alternatives have also varied considerably. Areas closer to Grays have tended to
have better networks with smaller towns in the east having fewer viable alternatives.
Both the demographics and transport alternatives have had measurable impact on
the intervention outputs and outcomes.
The map in Figure 4 shows Indices of Multiple Deprivation. The index combines
levels of income, employment, health, education and skills among others to rank
each area of the country, grouped geographically by Lower Super Output Areas.
Areas coloured red on the map represent the 15% most deprived areas in England
and Wales and green the 15% least deprived.
Thurrock contains 8 of the most deprived areas with parts of Tilbury in the top 5%
most deprived. In contrast to this, 10 areas including parts of West Thurrock,
Chafford Hundred, Stanford-le-Hope and Corringham are in the 15% least deprived
areas of England and Wales. This variation in deprivation alone brings significant
challenges to engagement for example resident’s motivations and interests are likely
to vary and they will not respond to the same messaging.
The key benefits associated with the length and duration of the intervention included
having the time to divide key areas based on location and demographics, and
therefore enabling the approach used to be adapted to maximise engagement
opportunities. This allowed for each intervention period to focus on particular
alternatives to the car and effect different approaches to delivery, such as community
engagement, rather than a standard approach across the project duration.
Another key benefit of delivering an ongoing project was the exposure that was
generated to the Travel Thurrock brand. Including pilot and legacy phases the project
has been highly visible to the public for 4 years; this increased recognition for the
Travel Thurrock brand and what it was achieving.
Measuring Sustained Change
Results from the Travel Thurrock PTP project have been used to follow the journey
participants made throughout the course of the intervention and beyond. Data
collected from engagement outcomes and follow-up surveys between 2012 and 2014
have been supplemented by newly gathered data which examines the levels of
sustained change achieved as a result of the intervention.
Implementation, follow-up and sustained change results have been translated to the
Change Model which is our adaptation of the Transtheoretical Model of Change 1.
This shows what stages of change the population of the borough are in specific
points in time. Monitoring Survey data has quantified the rates of sustained change
3, 18 and 30 months after intervention in order to assess the impact of relapse back
into previous, less sustainable, habits. The Change Model is discussed in greater
detail in the next section.
8
Figure 4: Thurrock Indices of Multiple Deprivation
9
3
METHOD
As part of the Travel Thurrock project, monitoring data was collected before, during
and after the intervention in order to quantify outputs and outcomes. The metrics
measured included participation rates, reasons for non-participation, mode share
before and after, and increases or decreases in the number of trips made by different
modes. Data on levels of sustained change are not usually gathered as part of the
PTP intervention due to limits on contract periods.
Unusually; in order to assess the longer-term impacts of Thurrock’s PTP intervention,
participants were contacted again between 3 and 30 months after the normal
monitoring phase. This sustained change data was collected for participants who:


Stated they had made a change in the final follow-up survey (4-6 weeks after
the intervention); or
Intended to make a change as a result of their contact with Travel Thurrock,
but had not yet made it at the point of follow up.
The results of the sustained change survey were used to show the number of
participants in these two groups who made or maintained a positive change, made a
different change or reverted back to their previous travel behaviours.
Within the analysis consideration was given to whether the demographic type and
access to public transport had any significance on the long-term impacts of PTP and
effectiveness of the intervention.
The number of respondents to the PTP and after surveys is shown in Table 1.
Table 1: Number of PTP and Survey Respondents
Stage
Number of respondents
Contact
28,633 (contacts)
First Follow-up (4-6 weeks after)
1,505
Sustained Change (3-30 months after)
162
The Change Model
The change model shown in Figure 5 shows the stages in behaviour change
following an intervention. The change model is adapted from Prochaska and
DiClemetes Transtheoretical Model1 that integrates leading theories of behaviour
change from various different interest areas. The model is applied to the various
stages of a PTP intervention which, in this study, quantifies the relapse and
termination stages up to two and a half years after the intervention has been
completed.
The relationship between the Cycle of Change and engagement outcomes can be
seen in Figure 5 with each stage described below:
10







Individuals who could not be contacted remain unknown and are classified as
pre-contemplative; they do not feature in this analysis;
Individuals who were contacted and had a conversation with a Travel Advisor are
classed as contemplative;
Individuals who participated in the project and received resources moved into the
preparation phase. Those who also participated in the project, have not made a
change but intend to also remained in this phase;
Participants who went on to try travelling by different means moved into action;
Participants who maintained the changes they made moved into the maintenance
phase of the cycle. During the contact phase some participants chose not to
participate as they already travelled sustainably, these have been classed in
maintenance but only feature in the contact results;
Those who did not maintain the changes they made and made no additional
changes moved to relapse;
Participants who did not make a change and stated they do not intend to after
receiving resources leave the cycle and terminate.
At any time in the cycle, individuals can move back (relapse) or forwards (change)
between the stages or may also at any point terminate their modified behaviour.
Figure 5: The Change Model and Personal Travel Planning Outcomes
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4
RESULTS
Results from the implementation phase, follow-up and sustained change survey are
presented in this section. Analysis is presented for the aggregated results of data
from all three years as well as results which have been shown on maps in order to
illustrate the variations of outcomes in each area.
The diagram in Figure 6 shows the route that residents have taken through to
maintenance and which has been analysed in the following sections. The aggregated
results for the PTP project have been presented in Figure 7. Disaggregated results
showing variations by location and sustained change are provided in Figure 8 to
Figure 11.
Figure 6: Path of Analysis
Contacts
Aggregated results in Table 2 and Figure 7 show that the majority of residents who
spoke to a Travel Advisor moved into either the stages of contemplation or
preparation. Residents who Travel Thurrock was not able to contact were excluded
from the analysis.
Residents who spoke to Travel Thurrock but did not participate are categorised as
contemplative. During the conversation it is assumed that the resident will have
considered their options but for a variety of reasons did not wish to participate in the
project. Contemplators account for 36% of residents who were contacted.
12

49% of residents who were contacted participated in the Travel Thurrock
intervention by requesting tailored resources to be delivered. These
‘participants’ entered the preparation stage of the cycle.

15% of households contacted informed the Travel Advisors that they already
travelled sustainably. These non-participating households have been mapped
on the cycle as maintaining positive travel behaviours but are excluded from
the analysis as there was no further opportunity for follow-up.
Disaggregated implementation results show how the level of participation varied
across the areas of Thurrock. Whilst on the whole levels of contact were fairly
consistent, non-participation varied more. For example, the contact outcomes for the
proportions of residents who were in the contemplation stage were subject to the
greatest range of variation. Contemplation or non-participation ranged between 31%
in Corringham to 53% in Orsett.
The main factors affecting levels of PTP uptake were access to good quality public
transport and demographic type. Areas where residents chose not to participate in
the intervention typically had fewer viable travel alternatives such as Orsett, where
bus services are limited.
Areas with higher concentrations of State Support households also saw lower levels
of uptake of the PTP offer but also highest levels of non-participation due to residents
stating they already travelled sustainably.
Table 2: Outcomes after contact phase
4.1
PTP Outcome
4.2
Stage of change 4.3
Total
Number
4.4
Percent
28,633
100%
4.5
Non - Participant 4.6
Contemplation
10,423
36%
4.7
Participant
4.8
Preparation
13,998
49%
4.9
Already Travels
Sustainably
4.10
Maintenance
4,212
15%
Follow-up
Aggregated results for the whole of Thurrock are shown in Table 3 and Figure 7Error!
Reference source not found. from the first follow-up surveys conducted four to six
weeks after the visit by Travel the travel advisors. Results show the percentages of
residents who moved into either the action phase having made a change, stayed in
the preparation phase or, terminated. The outcomes of this follow-up were:
13

21% of participants remained in the preparation stage four to six weeks after
their visit. During the follow-up they stated they had not yet made a change
but intend to.

19% of participants had moved into the action stage after making a change to
a more sustainable means of travel.

The remaining 60% of participants terminated at this stage by stating they
would not be making a change.
Figure 9 shows variations in results from the follow-up surveys. Interventions that
took place in Grays and West Thurrock had significantly more individuals remain in
the preparation phase of the cycle of change during the follow-up than those
surveyed in east Thurrock. This resulted in fewer individuals moving into the action
phase in the weeks immediately after the intervention.
The rates of termination experienced in the outlying, less urbanised areas are higher
than the more urbanised areas of Grays, Chadwell Saint Mary and South Stifford.
The effect of the higher rate of drop-out leaves fewer individuals to move into action
and maintenance stages. Once again access to public transport seems to be a key
factor in the extent of Personalised Journey Planning uptake, especially when
seeking alternatives to the car for commuting journeys.
Table 3: Outcomes after first follow-up survey
PTP Outcome
Stage of change
Total
Number
Percent
13,998
100%
Intend to make a change
Preparation
2,924
21%
Made a change
Action
2,620
19%
Will not be making a
change
Termination
8,455
60%
Sustained Change
This section discusses the results of the sustained change survey conducted 3-30
months after contact with residents who had previously been in the preparation or
action stage of the cycle of change. Aggregated results in Table 4 and Figure 7 show
that up to 30 months after the intervention 80% of participants had moved from the
action stage and were maintaining the changes they had made as a result of the visit
by the Travel Advisor.
The remaining 20% of participants who had made a change reverted back to their
previous behaviours and moved to the relapse stage.
Figure 10 shows how the levels of sustained change varied across the three
implementation periods from 2012-14; results are grouped by year of implementation
14
and labelled to highlight the number of months elapsed between the end of the
intervention and the sustained change survey.
Levels of sustained change up to 30 months after the intervention were similar
across both time and place. The percentage which had relapsed back to old habits
was:



20% after 3 months;
17% after 18 months; and
23% after 30 months.
This implies that once the new behaviour has been tried out either it is adapted quite
quickly or abandoned. Once adopted it becomes a new habit which remains stable
until there is another disruptive event.
Table 4: Sustained Change Results: Maintenance
PTP Outcome
Stage of change
Total
Number
Percent
2,620
100%
Maintained the change I
made
Maintenance
2,096
80%
Reverted to previous
behaviours
Relapse
419
20%
The sustained change survey also revealed how over time, an increasing proportion
of those intending to change did turn this intention into action. Even after 30 months
though, a fifth remained in the preparation stage. Figure 11 shows the results for
participants who were contacted in the follow-up survey four to six weeks after
intervention, were still in the preparation stage and had not made a change but
intended to. The overall figures can be seen in Table 5 below.



15
3 months after the intervention 42% of participants who intended to change
remained in the preparation phase and stated that they still intended to make
changes. 19% had actioned their change and a further 38% stated they would not
be making a change.
18 months after intervention 67% of participants who still intended to make a
change after the follow-up survey had gone on to do so and moved to action.
27% of residents terminated any change and 7% who intended to change
remained in preparation
30 Months after intervention almost half (50%) of participants moved from
preparation to action. 37% terminated by stating they would not be making a
change and a further 14% reported on still in tending to make a change and
remained in preparation.
Table 5: Sustained change results: Action
PTP Outcome
Stage of change
Total
Number
Percent
2,924
100%
Intend to make a change
Preparation
556
19%
Made a change
Action
1,374
47%
Will not be making a
change
Termination
994
34%
Figure 7: Aggregated Results for Thurrock Personalised Journey Planning
16
Figure 8: Cycle of Change - Contact Phase
17
Figure 9: Cycle of Change - Follow-up Phase
18
Figure 10: Cycle of Change - Sustained Change: Maintenance
19
Figure 11: Cycle of Change – Sustained Change: Action
20
5
ANALYSIS
There are many local factors which affect the outputs and outcomes of a behaviour
change project. In the example of Thurrock Personalised Journey Planning the
demographic profile of participants (as seen in the Smarter TravelStyle analysis) and
access to good quality, regular public transport alternatives have had the greatest
effect.
Implementation Analysis
Results show that more urbanised, better connected areas with more alternatives to
the car can return a greater uptake in the number of individuals willing to make a
change to how they travel. This in turn feeds the number of individuals who can
action a change to their travel behaviour.
Mode change results from the 2013 intervention in South Ockendon and Chafford
Hundred indicated the highest levels of change to public transport. Bus mode share
increased by 19% amongst participants surveyed. This result also coincides with the
highest levels of participation and sustained change, 18 months after intervention.
For residents not served well by bus or rail services encouraging change to more
sustainable modes can be more challenging. This especially applies to individuals
working during unsociable hours or those who cannot use a direct bus service and
may need to travel to an interchange station first, adding considerable time and
additional expense to their journeys.
Despite alternatives to the car not being as readily accessible in areas of east
Thurrock, a tailored intervention was used to combat the lower levels of access to
public transport as well as finding ways of engaging with harder to reach
communities as identified by the Smarter TravelStyle analysis. Targeted walking
interventions capitalised on access to surrounding countryside and Thurrock’s Beat
the Street initiative to create more of a buzz about walking – this was particularly
effective for parents on the school run and helped participants make better use of
leisure time.
As a result, increases in walking were higher than any other areas in the borough
with a 27% increase in walking trips amongst participants. Active travel in this area
was especially important from a public health perspective where individuals living in
areas of greater deprivation also experienced poorer health outcomes.
Sustained Change Analysis
There has been some variation in the amount of time it takes participants to make a
change after the intervention. Results from the sustained change surveys show that
3 months after intervention a large proportion of residents remain in the preparation
stage and have not gone on to either make a change or terminate.
18 and 30 months after the intervention the proportions of residents in the
preparation stage of change is considerably lower than 3 months after, suggesting
that the time required for action to take place is between 3 and 18 months for some
residents. In the case of the intervention taking place in 2014 the specific local
challenges may have had an impact on the time needed to make a change. This is
consistent with previous experience which found that one of the roles of PTP is to
21
“prime” people so that when an event in their lives triggers consideration of travel
habits they are prepared to consider sustainable options.
The Department for Transport estimates in their LSTF value for money assessment 3
that the assumed average decay rate of Smarter Choices measures to be 33% per
year. Data from the Travel Thurrock project would suggest that there has been much
less decay between years, supporting the hypothesis that once people have
successfully made a change this then becomes a new ingrained habit. In fact, the
evidence of the Personalised Journey Planning intervention ‘wearing-off’ between 18
and 30 months after intervention is much lower and suggests relapse rates could be
as low as 10% per year and therefore benefits extend beyond 5 years.
The implications of the lower rate of decay is that Smarter Choices interventions
deliver better value for money than previously assumed with greater benefits to host
areas.
6
CONCLUSIONS
The rates of change and sustained change in Thurrock have been influenced by
three key factors:



The quality and availability of alternatives to the car in the target area;
The demographics of the target area; and
The ability for the delivery team to adapt to the local conditions and provide a
tailored intervention.
The factors above influenced the number of residents who participated and prepared
to make a change, the number of participants who moved on to action and
maintained their change and consequently, the proportions who decided to terminate
and relapse.
In addition to the three key local factors, softer factors such as the quality of the
Personalised Journey Planning team also impacted the level of change. Over the
course of the Travel Thurrock project a core team of Project Staff and Travel
Advisors worked over the entire duration of the project, ensuring delivery was of a
consistently high standard throughout.
In order to ensure high standards of delivery were maintained, the delivery team
received ongoing Motivational Interviewing and engagement training throughout the
project. Ongoing training built on the Travel Advisors’ experience and local
knowledge of the specific challenges in the area resulting in the best possible
outcomes to be achieved.
Personalised Journey Planning interventions which target larger populations,
delivered over longer time frames may have greater impacts than similar smaller
projects delivered over shorter timeframes. However, larger projects require tailored,
targeted delivery to be planned and deployed, reflecting the local conditions of each
area, and also the need for lessons learnt to be incorporated within the life span of
the project.
A prolonged presence in the target area may also add to the effectiveness of
delivering long lasting change in the targeted communities. Participants who remain
in the stage of preparation may need an extra nudge to move into the action stage. In
22
order to help these individuals, a prolonged presence and increase in number of
opportunities for contact is desirable in order to effect a change – this may be
particularly true for harder to reach Smarter TravelStyle segments.
Sustained change surveys with participants have revealed that the amount of time
needed to make a change after the intervention can vary between people. In some
cases the more pro-active participants can move from the preparation to action
stages within 1 to 3 months; however a significant proportion of participants needed
between 3 and 18 months to either make a change or terminate.
Rates of relapse between 3 and 30 months after the intervention are much lower
than generally assumed and vary very little over time, suggesting that the effect of a
Personalised Journey Planning intervention is more substantive and longer lived that
previously estimated by the DfT.
Notes
1
Prochaska, J. et al. (2008) The Transtheoretical Model and Stages of Change:
Health Behaviour and Health Education. 4 98-104.
2
Rollnick S, Allison J, Ballasiotes S, Barth T, Butler C, Rose G and Rosengren D
(2002) Variations on a Theme: Motivational Interviewing and its Adaptations. Miller
W and Rollnick S
3
Department for Transport (August 2014) Value for Money Assessment for the Local
Sustainable Transport Fund.
23

Using the Change Model to Interpret Variations in PTP Results

Transcription

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