Feasibility and Acceptability of a Physical Activity Behavior Change Intervention for Improving Self-efficacy, Automaticity, and Physical Activity Levels in People With Parkinson's Disease
Phase: PHASE1
Conditions: Parkinson's Disease
Sponsor: Teachers College, Columbia University

 
 
 
 
Feasibility and acceptability of a physical activity behavior change intervention  
for Parkinson’s disease 
 
NCT03696589 
 
 
Study Protocol 
 
November 15, 2019 
 
 
 

Participants 
Participants were recruited from a purposive convenience sample. Study recruitment 
fliers were distributed to local neurologists and therapists who work with PwPD, support groups, 
and within the Neurological Institute at the Columbia University Medical Center. Flyers were 
also distributed at the 2018 PD Unity Walk in Central Park, NYC, where the Columbia 
Movement Disorder Division had an official booth. At the booth, the investigator took down 
names and contacts of individuals who expressed an interest in the study and then contacted 
them after the event to see if they wanted to participate and be screened for qualification. 
Potential participants who met the inclusion/exclusion criteria were also contacted from the NRL 
PD registry. The NRL PD registry contained contact information of PwPD who consented to be 
contacted for new PD-related studies at NRL. Finally, the study was registered on 
clinicaltrials.gov (Clinical Trials Registration NCT03696589) which led to it being posted on the 
Michael J Fox (MJF) Trial Finder. Participants were not excluded based on gender, class, or 
race.  This study took place in the Neurorehabilitation Research Lab (NRL) at Teachers College, 
Columbia University. 
Participants were included if they were: 1) between the ages of 18 and 85 years of age; 2) 
had a neurologist confirmed clinical diagnosis for Parkinson’s disease H&Y stage I or II 1; 3) 
able to ambulate indoor and outdoor without assistance or the use of an assistive device; 4) 
successful completion of the Physical Activity Readiness Questionnaire (PAR-Q)2 safety screen 
or medical clearance from their general practitioner. The age group was limited, given the 
research questions to be addressed.  The incidence and prevalence of PD are 1.5–2 times greater 
in males than in females,3 thus we anticipated there would be a greater enrolment of men than 
women 
Participants were excluded if they (1) had a musculoskeletal injury that would prevent 
them from participating in an exercise program; (2) had another neurological disease or disorder 
such as stroke; or (3) if they were already engaging in aerobic exercise for at least 30 minutes for 
five or more days per week.  
 
Study Design 
A feasibility design was used to assess if the Pre-Active PD intervention can work in 
regards to acceptability and implementation4 and to investigate the effect estimates in regards to 
PA levels, self-efficacy, motivation, and self-perception of performance. Given the stage of the 
presently proposed question, an open pre-post cohort design was selected. The selected cohort is 
adults with early stage PD (H&Y I-II). An open cohort was selected to present less obstacles for 
attaining the desired sample size for the study. The design was prospective, which allowed the 
investigators to obtain baseline exposure data in real time and then follow the participants to 
measure the occurrence of the health outcome.4 In addition, there was a retrospective element to 
the design: the inclusion of post-intervention questionnaires designed to assess retrospective 
acceptability of the intervention. 
 
Procedures 
Participants were consented to be screened over the phone and then screened for 
eligibility using the inclusion/exclusion criteria and PAR-Q. Participants were then scheduled 
individually to come to the NRL for their baseline assessments. Informed consent, baseline 
assessments and ActiGraph administration were carried out at week 0 by a trained research 
assistant. The ActiGraph was worn for seven consecutive days and then returned to NRL. The 

intervention was delivered by an occupational therapist. The first one-to-one session occurred on 
week 1, and subsequent sessions followed on week 2, 3, 6, 10, and 14. On the alternate weeks 
when there were no sessions, the participants were contacted via phone or email for check-ins. 
At week 15, the follow-up assessments and another ActiGraph were administered by the research 
assistant,. At week 16 the ActiGraph was returned via mail. See figure below for study schema 
diagram. 
 
 

Figure. Study schema diagram 
 

Intervention. The Pre-Active PD intervention underpinnings and components were 
described in detail in chapter one (see figure II for Logic Model).  The intervention was 
delivered by the investigator who is a licensed occupational therapist with experience working 
with PwPD, PA coaching, and MI. For the intervention sessions, participants had the option of 
doing them in person at NRL or remotely via a secured web-based server, Zoom. One week 
following baseline measures, participants received their first of six one-to-one sessions that 
occurred over the following 14 weeks (week 1, 2, 3, 6, 10, and 14). The therapist checked-in 
with the participant via phone or email to provide additional support and feedback on the weeks 
when the participant did not have one-to-one sessions (week 4, 5, 7, 8, 9, 11, 12, and 13).  
At the first session, the therapist used the University of Rhode Island Change Assessment 
– Exercise 2 (URICA-E2)5–7 to determine which stage of change the participant was beginning 
with in regards to PA. After the stage of change was identified, the therapist introduced the Pre-
Active PD workbook and gave an overview of the program and timeline. The therapist used the 
MI techniques (described in chapter one) in alignment with the SDT in in order to facilitate 
progression through the TTM stages for PA behavior change. 8–10  
Towards the end of the first session, the therapist employed the mCOPM and helped the 
participant identify 3-4 PA goals. The goals were related to frequency, duration, and intensity of 
selected exercises. Finally, the therapist asked the participant if they wanted to use the Fitbit 
(Charge 2 model) to monitor their PA. If the participant said yes, the therapist provided a pre-
charged Fitbit device with charger. The therapist showed the participant how to download the 
Fitbit app, create a Fitbit account, sync the device to their smart phone, and explained how to use 
it. Before concluding, the therapist scheduled their next session for the following week and asked 
if they wanted to do it in person at NRL or remotely via Zoom.  
After the participant left, their Fitbit account was set up with Fitabase program a web-
based platform that integrates FitBit data from users (Small Steps Lab, Inc; San Diego, CA, 
USA). During the intervention, participants' PA behaviors were monitored remotely through the 
Fitabase platform, whereby the therapist could view summaries of the participants’ PA levels, 
and heart rate zones throughout the day. For each of the remaining five sessions, the goals were 
revisited, the Fitbit data was reviewed, and discussion ensued regarding participants’ successes 
or struggles, and themes from the Pre-Active PD workbook.  
 
Assessments 
Demographic data and assessments were collected to illustrate the participant 
characteristics at baseline. Feasibility was assessed at follow-up in regards to the domains of 
acceptability and implementation (see table 1). Additional outcomes measures were administered 
at baseline and follow-up to assess effect estimates in the areas of self-efficacy, motivation, PA 
levels, and self-perception of performance and satisfaction (see table 2).  
 
Participant Characteristics. At baseline, demographic data were recorded for each participant 
including age, gender, H&Y score, height, weight, date of diagnoses or onset of symptoms, and 
most affected side. In addition, the Montreal Cognitive Assessment (MoCA)11 was administered 
at baseline. The MoCA is a 30-point cognitive screening instrument. A score of less than or 
equal to 26 is indicative of cognitive impairment.12 The MoCA was used to assess presence and 
severity of cognitive impairment. 
The University of Rhode Island continuous measure (URICA-E2)13 was administered by 
the therapist at the beginning of the first session to assess the participants’ readiness to change 

with regard to exercise behavior, based on the TTM stages of behavior change. The URICA-E2 
is a 24-item, 5-point Likert-sale, questionnaire. Each item has a statement that reflects an 
intention toward exercise, with responses ranging from one “strongly disagree” to five “strongly 
agree”. Internal consistency of this questionnaire was 0.80 to 0.93. 6  
 
Feasibility. Feasibility was assessed in regards to acceptability and implementation fidelity. 
Table 1 includes a summary of the feasibility measures, variable names, and the corresponding 
feasibility domain. 
 
Table 1. Feasibility measures 
Feasibility 
Domain 
Outcome Measures 
Variable 
Name 
When 
Acceptability 
Participant completion of 
 ≥ 75% of sessions 1, 2 & 3 
Adherence 
Post follow-
up 
Acceptability 
> 75% of participants retained at follow-up 
Retention 
Post follow-
up 
Acceptability 
Fitbit Wear-time, or written logs 
PA log 
During 
intervention 
Acceptability 
Theoretical framework of acceptability 
questionnaire 
TFAQ 
1x 
Follow-up 
Acceptability 
Perceived Autonomy Support Healthcare 
Climate Questionnaire (Williams, Freedman, 
& Deci, 1998) 
PAS-
HCCQ 
1x 
Follow-up 
Implementation 
Rating Tool to Assess Fidelity of Intervention 
Delivery 14 
Fidelity 
Post 
follow-up 
 
Adherence and Retention. Adherence was defined as the participant’s commitment to the 
Pre-Active PD program through continued participation. Participation in the one-to-one coaching 
sessions along with the Fitbit data provided insight to the level of adherence. An adherence rate 
of ≥ 75% of the participants completing session 1-3 and a retention rate of > 75% retained at 
follow-up were deemed appropriate to suggest feasibility of this intervention. This threshold for 
adherence was set relative to the number of visits required to discuss all content of the 
workbook, as modeled in the Engage-HD study.15  In addition, PA logs (i.e. Fitbit wear-time or 
written log) were also selected as it is recognized as a valid and acceptable method for measuring 
adherence. 16 The minimum threshold for adherence to PA logs was defined as valid data 
reported for at least four days or more in over half the weeks during the intervention for any one 
of the components.   
 
TFA Questionnaire (TFAQ). Informed by the Theoretical Framework of Acceptability 
(TFA),17 the TFA Questionnaire (TFAQ) was designed to inductively evaluate the retrospective 
acceptability of the Pre-Active PD intervention for patients with early stage PD by the present 
investigator. The TFAQ was not tested for reliability or validity. The TFAQ was designed to 
gather the participants’ thoughts and feedback regarding the intervention delivery and workbook 
post-intervention, and was administered once at the 15-week assessment. The TFAQ part I 
included 25-items, where participants were asked to rate each statement on a Likert scale from 1 

(strongly disagree) to 5 (strongly agree), with higher numbers indicating greater acceptability. 
Part I quantitatively measured 4 of the 7 theoretical constructs from the TFA: (1) affective 
attitude (how the participant feels about the intervention; items 1-4), (2) intervention coherence 
(the extent to which the participant understands the intervention and how it works; items 5-10), 
(3) perceived effectiveness (the extent to which the intervention is perceived as likely to achieve 
its purpose; items 11-18), and (4) self-efficacy (the participant’s confidence that they can perform 
the behaviors required to participate in the intervention; items 19-25). Specific questions for each 
TFA domain were constructed with respect to the therapist (items 1-3, 10, and 15-17), workbook 
(items 4-8 and 11), and intervention as a whole (items 9, and 12-14). Acceptability was indicated 
by a total score higher than 75 from the sum of items 1-25 on the TFAQ-part I. The intervention 
components were also analyzed in separate aggregates in the domains of therapist, workbook, 
and overall impression. Part II of the TFAQ was optional and included open-ended questions to 
gather qualitative data from the participant’s experience and feedback for the Pre-Active PD 
intervention. Acceptability was indicated by a total score higher than 75 from the sum of items 1-
25 on the TFAQ-part I. 
 
Perceived Autonomy Support Health Care Climate Questionnaire (PAS-HCCQ). The 
PAS-HCCQ is a 15 item questionnaire18 designed to assess constructs encompassed within SDT 
as it applies to health-care behavior.19. The PAS-HCCQ items were marked by a high internal 
consistency (Cronbach’s alpha = .96).20 The scores indicate the degree to which the therapist was 
perceived to be autonomy supportive. Each item is rated on a 7-point Likert-type scale ranging 
from 1 (strongly disagree) to 7 (strongly agree). Scores were calculated by averaging the 
individual item scores. As per instructions, before averaging the item scores, the score of item 13 
must be “reversed” by subtract the score on this item response from 8. For example, the score of 
3, when reversed would become 5. Higher average scores represent a higher level of perceived 
autonomy support.18 
 
Implementation Fidelity. An intervention fidelity rating tool14  was used to assess the 
extent to which the therapist promoted the components of SDT (autonomy, relatedness, 
competence, and general impression). Four items were rated on a 0-4 Likert scale, and then 
summed to produce a total score range of 0-16, with the higher scores indicating higher 
intervention fidelity. A licensed occupational therapist, who was not involved in the intervention 
delivery or the administration of the other assessments, was instructed on how to use the 
measure. The assessor viewed and rated 12 sessions (one from each participant), that had been 
previously recorded via Zoom. In addition to the ratings, the assessor identified quotes from the 
therapist and participant that illustrated promotion of autonomy, relatedness, and competence.  
 
 
 

Efficacy outcome measures. 
Efficacy of the intervention was assessed in regards to effect estimates comparing pre and 
post intervention for physical activity, self-efficacy, motivation and self-performance of 
performance and satisfaction on goals. In addition to measures of feasibility and acceptability, 
there were two primary efficacy outcomes: 1) change from baseline in moderate vigorous 
physical activity using Actigraph, and 2) change from baseline in the relative autonomy index 
(RAI) of the behavioral regulation in exercise questionnaire (BREQ-2).  Table 2 includes a 
summary of the efficacy outcome measures. 
 
Table 2. Efficacy Outcome Measures 
Effect Estimate 
Domain 
Outcome Measures 
Variable 
Name 
When 
Physical 
Activity 
Brunel Lifestyle Physical 
Activity Questionnaire 21 
Brunel-
PAQ 
2x, 
Baseline and follow-up 
Physical 
Activity 
Wearable activity monitor 
ActiGraph 
2x, 
Worn 7 consecutive 
days pre and post 
intervention 
Self-efficacy 
The Exercise Self-Efficacy 
Scale 22 
Norman-
SES 
2x, 
Baseline 
and follow-up 
Motivation 
The Behavioral Regulation In 
Exercise Questionnaire 23 
BREQ-2 
2x, 
Baseline and follow-up 
Self-perception 
of Performance 
& Satisfaction 
Modified Canadian 
Occupational Performance 
Measure 24 
mCOPM 
2x, 
First and last session 
 
 
Physical Activity Levels. The Brunel-PAQ is a 10-item questionnaire that measures both 
pre-planned and un-planned lifestyle PA 21 The Brunel-PAQ was designed to provide an online 
behavioral assessment to be used in conjunction with a 12-week personalized fitness program 
delivered through the internet, and was found to be a valid and reliable instrument. 25. The 
Cronbach alpha coefficient for criterion validity of the behavioral intention items was α = .9325. 
Internal consistency (Cronbach’s alpha) estimates for the Brunel-PAQ subscales were α = .90 for 
Planned PA α = .90, and α = .68 for Unplanned PA. 25  The BRUNEL-PAQ defined planned PA 
for participants as: “any activity that is scheduled into your daily routine, which may enhance 
your health, fitness, or wellbeing.”.25 Examples were provided, including brisk walking, 
gardening, cycling, team games, etc. 
Responses to each item in the PA subscale were provided on a five-point categorical 
Likert-type scale (continuous closed numerical scale). For example, answer options for question 
one included: (1) never, (2) 1–2 times, (3) 3–4 times, (4) 5–6 times, (5) 7 or more times. 
Participants were asked to base their responses on what a typical week is like for them. The 

planned PA subscale includes six items that were designed to measure the intensity, frequency, 
and duration of the identified activity. The unplanned PA subscale did not assess frequency 
because of its highly transient nature making it difficult to obtain validity.  
The ActiGraph™ GT9X quantitatively measured PA levels (step count, MVPA levels, 
and sedentary behavior) to assess change before and after the intervention. Actigraphy is a non-
invasive way of monitoring human rest/activity cycles and has been used to study PA levels and 
patterns in PwPD who have mild to moderate severity. 26–28 The ActiGraph™ GT9X is a reliable 
assessment of steps for PwPD or altered gait in both clinical and research evaluations. 29 The 
ActiGraph™ is an inertial measurement unit (IMU) which includes an accelerometer, a 
gyroscope, and magnetometer sensors to capture position and rotation, and wear time sensor. 
Participants were instructed to wear the ActiGraph™ secured on their hip by an elastic clip-on 
waist band on their hip for 7 consecutive days prior to receiving the intervention, and again after 
their last session. In addition, participants were asked to keep a written log, using handouts 
provided, to record times when the ActiGraph™ was removed and put it back on. Participants 
were instructed to not wear the device in water, such as when bathing or during water sports.  
Self-efficacy. Self-efficacy was measured by the Exercise Self-Efficacy Scale (Norman-
SES).22 The Norman-SES is an 18-item test that measures an individual’s self-efficacy to 
participate in exercise when numerous barriers are present, including both social and physical 
barriers. The measure employs a 5-point Likert scale for confidence, from 1 “not at all 
confident” to 5 “completely confident”, in the areas of negative affect (α = .853), excuse making 
(α = .829), must exercise alone (α = .869), inconvenient to exercise (α = .773), resistance from 
others (α = .853), and bad weather (α = .837). A score less than or equal to 54 indicated low self-
efficacy (18 items x Likert score of 3 “neutral”), a score between 54 and 72 (18 items x Likert 
score of 4 “confident”), and a score between 72 and 90 (18 items x Likert score of 5 “completely 
confident”) indicates high self-efficacy.  
Motivation. The Behavioral Regulation in Exercise Questionnaire (BREQ-2) measures 
the stages of self-determination continuum with respect to motivation to exercise.23 It is a 19-
item questionnaire, with a 5 point Likert scale from 0 “not true for me” to 4 “very true for me” 
for statements regarding PA engagement. For example, “I don’t see why I should have to 
exercise” (amotivation), “I exercise because other people say I should” (extrinsic), “I feel guilty 
when I don’t exercise” (introjected), “I value the benefits of exercise” (identified) and “I exercise 
because it is fun” (intrinsic). Acceptable internal consistency was previously demonstrated for 
the 5 subcategories: amotivation (items 5, 9, 12 & 19), external regulation α = .81 (items 1, 6, 11 
& 16),, introjected regulation α = .79 (items 2, 7 & 13),, identified regulation α = .78 (items 3, 8, 
14 & 17), and intrinsic motivation α = .93 (items 4, 10, 15 & 18). 30 A composite score of 
intrinsic motivation and identified regulation subscales represented autonomous motivation (α = 
.90). 30 A composite score of introjected regulation and external regulation represented controlled 
motivation (α = .78). 30 The BREQ-2 was scored by calculating the mean scores for each set of 
items per domain as indicated by its scoring key. 
Self-perception of Performance & Satisfaction. The Canadian Occupational 
Performance Measure (COPM)24 is a tool used to detect change in participant’s self-perception 
of occupational performance, in regards to performance and satisfaction, over time using two 10-
point ordinal scales, with 10 being the best score. The COPM was designed to enable 
personalized health care and identify issues of personal importance to the client. The COPM is a 
tool for initiating conversation about performance issues in everyday living, which provides the 
basis for setting intervention goals. More specifically, the COPM helps the therapist to: (1) 

identify problem areas in occupational performance; (2) provide a rating of the client’s priorities 
in occupational performance; (3) evaluate performance and satisfaction relative to those problem 
areas; (4) provide the basis for goal setting; and (5) measure changes in client’s perception of 
his/her occupational performance over the course of the intervention.  
The COPM has demonstrated strong content and concurrent validity31 as well as test–
retest reliability (intraclass correlation [ICC] .63 for performance, ICC .84 for satisfaction).32 The 
COPM has been demonstrated to be more meaningful for identifying and prioritizing problems 
in meaningful areas when compared to self-evaluation lists. 24,33 Though it has not been 
specifically studied with respect to PwPD, it is assumed to be valid for PwPD and recommended 
by the ParkinsonNet/National Parkinson Foundation (NPF) in their Guidelines for Occupational 
Therapy in Parkinson’s Disease Rehabilitation. 34  
For the Pre-Active PD intervention, the COPM was modified in a similar manner as 
previous research.35,36 For the purpose of the intervention, the occupational performance area 
focus was within the domain of active recreation or physical activity. Participants were asked to 
identify goals that they wanted to address over the duration of program, and each goal was rated 
for importance, performance, and satisfaction using the 10-point ordinal scale. The goals were 
then narrowed down to the 3 most important goals, similar to the Engage-HD intervention.14 
Participants had the option to modify or change their goals at each session as they progressed 
during the 4-month period. The original goals were revisited and scored again at the last session. 
The mCOPM total scores were calculated by summing the scores of each goal (scores 
range from 1-10), then dividing by the number of goals (3 or 4), to give the average score. This 
was done for both performance and satisfaction ratings separately. The average score was 
calculated for both the first and final session. The post-pretest change score was calculated by 
subtracting the first session score from the last session score. To date, research suggests that a 
change of 2 or more points represents a clinically important change.37,38   
 
Statistical Analysis 
Descriptive statistics summarized the participant characteristics and the results of the 
outcome measures. IBM’s Statistical Package for Social Sciences (SPSS) (version 26; SPSS Inc., 
Chicago, IL, USA) was used for inferential statistical analyses. Feasibility was evaluated in 
terms of acceptability and implementation. Percentages were reported for adherence and 
retention rates. Descriptive statistics were reported for the TFAQ-part I; the Perceived Autonomy 
Support Healthcare Climate Questionnaire (PAS-HCCQ)18; and fidelity rating tool14.  
Percentage of participants who selected Fitbit as their primary PA log was reported. 
Descriptive statistics were calculated for Fitbit data with regards to total percentage of time worn 
and daily step counts for the first and last 7 days. Data from the FitBit devices were synced with 
Fitabase program to provide sync events, wear time, number of steps per day, and moderate-
vigorous activity. The data were downloaded into a .csv file for all participants for the duration 
of their intervention (16 weeks).  Aggregate data were then calculated to provide mean and SD 
for all metrics 
Descriptive statistics were calculated for the outcome measures for baseline and follow-
up: PA levels (Brunel-PAQ and ActiGraph™), exercise self-efficacy (Norman-SES), motivation 
to exercise (BREQ-2), and self-perception of performance & satisfaction of goals (mCOPM). 
The mean difference between the baseline and follow-up was then calculated with a 95% 
confidence interval (CI). Effect sizes were calculated using Cohen’s d39, with d = 0.2 being 
considered a small effect size, d =  0.5 a medium effect size, and d = 0.8 a large effect size. 

Descriptive statistics were calculated for participants in the different stages of exercise behavior 
change (URICA-E2) with regards to their changes in exercise self-efficacy (Norman-SES) and 
planned PA (Brunel-PAQ). Descriptive statistics were also calculated for changes in kinds of 
PAs enjoyed (Brunel-PAQ) from baseline to follow-up. ActiGraph™ findings were calculated 
with regards to percentage of time spent in sedentary activity, percentage of time in MVPA, and 
daily step count.  
The accelerometry data were preprocessed as accelerometer data files (AGD files) using 
ActiLife software (ActiLife v6.13.2; Pensacola, FL, 2016) and then converted to CSV files with 
60-second epochs. Participants with less than 4 days (and a minimum of 1 weekend day) of 10 
hours per day of wear time were excluded from the results. Based on the results of earlier 
studies, 60 minutes of consecutive zero counts were classified as non-wear time. Non-wear time 
was excluded from calculations for each individual. 
Correlation coefficients were calculated to determine the relationship between: post-
pretest change scores of planned PA and self-efficacy; baseline self-efficacy scores and follow-
up planned-PA times; and post-pretest change scores of planned PA and unplanned PA and 
BREQ-2 measures of amotivation, external regulation, introjected regulation, identified 
regulation, and intrinsic regulation. 
 
 
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