Knee Arthroplasty Pain Coping Skills Training (KASTPain): A Randomized Trial
Phase: NA
Conditions: Knee Osteoarthritis
Sponsor: Virginia Commonwealth University

_____________________________________________________________________________________________________________________ 
Title: Knee Arthroplasty Pain Coping Skills Training (KASTPain): A Randomized Trial 
PI: Daniel L. Riddle, PT, PhD, FAPTA 
NCT #: NCT01620983 
Unique Protocol ID: HM14326 
Document approval date: July 20, 2012 
Document Type: Protocol and SAP 

_____________________________________________________________________________________________________________________ 
 
Specific Aims 
Recent data project that a total of 710,000 knee arthroplasty surgeries will have been conducted in 2010.  By 
2020, the frequency is predicted to more than double to over 1.5 million procedures. While arthroplasty is 
generally effective, approximately 25% of patients have unexplained disabling pain and impaired function a 
year or more after surgery, representing a significant cost to society in terms of lost productivity and medical 
costs. 
Recently published evidence by our group and others indicates that pain catastrophizing predicts poor 
outcome and that pain catastrophizing is the most powerful psychological predictor of unexplained poor 
outcome. Pain catastrophizing identifies approximately 50% of patients who will have longer term disabling 
pain and impaired function (e.g., an estimated 89,000 patients in 2010). Pain catastrophizing is the tendency to 
magnify pain sensations, ruminate upon them, and feel helpless when experiencing pain. It is also amenable to 
treatment via pain coping skills training. 
Pain coping interventions have been successfully implemented for patients with chronic musculoskeletal pain 
disorders, but have not been studied in a surgical population. Current practice guidelines for knee arthroplasty 
do not address the treatment of psychological distress, a major contributor to poor outcome. We propose to 
examine the efficacy of a pain coping skills training approach for patients scheduled for knee arthroplasty and 
who are at high risk for poor outcome. The proposed study will provide data that has strong potential to support 
a new treatment paradigm to improve upon current clinical practice. 
Our long-term goal is to improve the outcomes for individuals receiving knee arthroplasty.  In the current 
application, we propose a three-armed multicenter clinical trial; the “Knee Arthroplasty Pain Coping Skills 
Training (KASTpain) Study.” The study extends work our team began with our R-34 funded grant. The 
KASTpain trial will test whether a pain coping skills training intervention improves the outcomes for 
arthroplasty patients with high pain catastrophizing pre-operatively, relative to arthritis education or usual care.  
Specific Aim 1. To assess the efficacy of pain coping skills training in reducing knee pain and improving 
function. Our two primary hypotheses (to be tested in the clinical trial) are the following: 
 
Hypothesis 1a.  Pain coping skills training is more effective than arthritis care education in decreasing 
knee pain during functional activities.  
 
Hypothesis 1b.  Pain coping skills training is more effective than usual care in decreasing knee pain 
during functional activities. 
We also will examine one secondary (hyp. 2) and one tertiary (hyp. 3) hypothesis. 
 
Hypothesis 2.  Pain coping skills training is more effective than arthritis education or usual care in 
improving self-reported function, physical performance, pain intensity, pain catastrophizing, and patient 
global ratings of improvement. 
 
Hypothesis 3. Pain coping skills training will reduce direct medical costs and indirect (i.e. patient time) 
costs relative to arthritis care education and usual care. When accounting for costs associated with pain 
coping skills training, the intervention will be cost saving or cost-effective relative to arthritis care 
education and usual care as measured by the incremental cost per quality-adjusted life-year. 
Specific Aim 2. To determine if treatment benefits of pain coping skills are mediated by changes in pain 
catastrophizing: 
 
Hypothesis 4. Changes in pain catastrophizing that occur over the course of pain coping skills training 
will mediate treatment-related improvements in pain and self-reported function during recovery. 
 

_____________________________________________________________________________________________________________________ 
Research Strategy 
 
Significance: Specific Aim 1 
Knee arthroplasty surgery (TKA) is a common and generally effective procedure.1 For example, projections 
estimate that 3.5 million procedures will be conducted annually by 2030.2 Cost data for TKA also are 
impressive. Mean procedural charges per patient in 2003, reported in 2005 dollars, were $38,000 per primary 
surgery and $48,000 per revision surgery.3 If these procedural charges data were extrapolated to the 2010 
volume data projections, procedural charges would total approximately $28 billion dollars annually. 
Serious early surgical complications such as venous thromboembolism or joint infection lead to poor outcome.  
However, the incidence of these adverse events is very low - on the order of 2% of all surgeries. Failure of the 
prosthesis is typically a late complication occurring several or more years following surgery and accounts for 
approximately 5% of poor outcomes.4 The great majority of “poor” outcomes following knee arthroplasty are 
attributed to disabling pain and impaired function not attributable to early complications or prosthetic loosening. 
Pain is the predominant complaint of patients seeking total knee arthroplasty.5-7 In large patient samples, 
improvements in pain or function scores have consistently been on the order of 40% to 60% relative to 
baseline, from 6 months to 2 years postoperatively.8-16 However, some studies clearly elucidate the number of 
patients who respond poorly to the surgery. For example, Puolakka and colleagues found that 36% of 433 
patients reported daily life disturbing pain and 27% had disturbed sleep four months or more after surgery.17,18 
Hawker et al. reported similar estimates 2 to 7 years following arthroplasty.19  
Only a third of patients report no functional problems following surgery 20 and approximately 20% report 
dissatisfaction with their functional ability a year or more after surgery.21 Functional deficits following surgery 
are observed in a wide range of activities, with up to 40% of patients still requiring the use of an assistive 
device to ambulate.19 
The problem of disabling osteoarthritis (OA) pain and reduced function is a large and as yet unsolved problem 
that has a dramatic impact on quality of life and productivity. For example, revision surgery rates are impacted 
by persistent pain and impaired function. Roberts and colleagues conducted a survival analysis of 4400 
patients with knee arthroplasty and found that 15 years following surgery, a total of 239 knees required revision 
and up to 35% were for unexplained pain. Extrapolating to current estimates, as many as 35% of 55,000 
revision arthroplasty surgeries in the US in 2010 may be attributable to unexplained persistent pain and 
subsequent poor function.22  
A barrier to progress in this field is that traditionally, knee arthroplasty has been presumed to be a highly 
effective procedure. The culture in clinical practice has historically been to forgo routine screening for patients 
at-risk for post-surgery persistent pain or compromised function. This culture has potential for change, 
however, because recent research has begun to acknowledge that unexplained poor outcomes occur.  
Predictors of these poor outcomes following knee arthroplasty are being identified. 23-26 Among the most 
consistent and powerful psychological predictors of poor outcome following knee arthroplasty is pain 
catastrophizing.17,25,27-31  
Additional impetus to address the issue of persistent pain was proposed by NIH. An NIH consensus panel was 
recently convened to review existing evidence on the use of knee arthroplasty surgery and to make 
recommendations for future research to improve the care for these patients.32 The panel placed high priority on 
research examining the impact of perioperative interventions for these patients. Our proposed trial would 
specifically target this research need. If a high-quality trial demonstrated that pain coping skills training was 
successful at improving outcomes for at-risk patients with poor pain coping, and was cost effective, current 
clinical practice paradigms could be significantly improved. 
 
 

_____________________________________________________________________________________________________________________ 
Significance: Specific Aim 2 
As Vlaeyen and Morley note, an important barrier to improving the effects of pain coping interventions is the 
use of a “one size fits all” approach to applying the intervention.33 Systematic reviews have consistently 
demonstrated the efficacy of pain coping skills training and other forms of behavioral treatment for patients with 
a variety of musculoskeletal disorders.34-36 However, effects generally are modest with effect sizes of 0.5 or 
less; a substantial proportion of patients receiving pain coping skills training do not appear to benefit.37,38  
Vlaeyen and Morley suggested that one way of improving outcomes is to better match the behavioral treatment 
to patient characteristics.33 To address this issue, we have intentionally selected for treatment a sub-group of 
patients with high levels of pain catastrophizing, who we hypothesize will likely experience substantial benefits 
from pain coping skills training.   
Testing for the presence of mediation (illustrated in Figure 1) will allow us to determine the extent to which pain 
catastrophizing28,29,39 mediates the relationship between pain coping skills training and outcome. The dashed 
line between pain coping skills training and WOMAC Pain 
represents the hypothesized mediation (either partial or 
complete) of pain coping effects by pain catastrophizing. 
Understanding whether catastrophizing is a mediator for 
pain coping skills treatment response will provide a 
causative explanation for how pain coping skills training 
effectively improves outcomes following knee 
arthroplasty. If our study finds that pain coping skills 
training (CST) is effective and that pain catastrophizing 
explains these effects, the field of orthopaedic surgery 
could experience substantive changes in the way in 
which patients with knee arthroplasty are treated; to the 
benefit of many patients. Surgeons may begin to routinely 
screen for high pain catastrophizing and initiate pain 
coping skills training for selected patients.  
 
Innovation: Specific Aim 1 
Current clinical paradigms do not discuss formal identification of patients at-risk for poor outcome due to poor 
pain coping.40 Nor do these paradigms address the use of perioperative interventions to reduce poor outcome 
risk. The current application challenges this practice paradigm. If our trial is successful, as we anticipate it will 
be based on our pilot work, the research will provide strong evidence to reconsider this traditional approach 
and may improve outcomes for thousands of patients who currently are at-risk for poor outcome.  
Previous work by our group29 and others27,28,31,39 has identified a TKA patient subgroup at high risk for poor 
outcome. Patients with high levels of pain catastrophizing have been consistently shown to have a higher rate 
of persistent pain and compromised function compared to non-catastrophizers. Our study is innovative 
because it is the first trial, to our knowledge, to target a specific surgical subgroup of patients at risk for poor 
outcome. In addition, we completed a search of ClinicalTrials.gov and the World Health Organization registry 
portal on June 1, 2011 and found no trials examining the impact of pain coping skills behavioral interventions 
for patients with knee arthroplasty. 
There is strong evidence from multiple systematic reviews that pain coping skills training and other similar 
behavioral interventions are effective for non-surgical patients with arthritis and other chronic conditions.34,41,42 
No studies were found that targeted patients undergoing surgery for chronic pain. Our proposed intervention is 
innovative in that it specifically focuses on cognitions and coping related to pain and was designed specifically 
for patients with knee arthroplasty. For example, the intervention accounts for the unique needs, interests and 
Usual Care
Pain Coping
Skills Training
Arthritis
Education
WOMAC
Pain Scale
Pain Catastrophizing
Scale
Independent
Variable:
3 Treatment
Arms
Mediator
Outcome
Variable
     Figure 1

_____________________________________________________________________________________________________________________ 
concerns of patients who are undergoing knee arthroplasty surgery. Along these lines, the intervention 
addresses patient catastrophic thoughts and concerns about pain that can arise during recovery following knee 
arthroplasty,14 43 and strategies for coping with pain and pain-related thoughts following knee arthroplasty. In 
summary, modifications we have made to CST make it uniquely well suited to address pain catastrophizing. 
The training format for each of the skills has been specifically modified to include training experiences that (1) 
help patients identify and evaluate maladaptive thoughts related to pain and (2) provide a means of teaching 
them to alter catastrophizing cognitions to more adaptive and realistic ones in order to reduce pain and 
improve function.  While newer technologies such as web-based delivery show promise, current trial evidence 
is lacking for these technologies in an older OA patient group with high catastrophizing. Furthermore, our 
elderly sample would likely have difficulty with these new technologies. Research team members have 
successfully used similar interventions in numerous trials for patients treated medically for knee osteoarthritis, 
low back pain and spinal cord injury.44-51 In sum, this body of work demonstrates the ability of the investigative 
team to organize and conduct innovative behavioral studies in patients with arthritis and chronic pain. While the 
intervention will be flexible to allow for individual patient preferences and differences, the essential elements 
will be well defined in both a therapist and patient manual that was developed during the R34 award. In 
addition, under the leadership and guidance from a nationally recognized expert in cost analysis (Dr. Shelby 
Reed) we will assess the cost effectiveness of the CST intervention. Our trial is innovative in that it will provide 
additional cost data for policy makers to judge the credibility of the intervention.  
We have modified conventional coping skills training in ways that not only make it particularly well suited to 
address pain catastrophizing but that are also are quite innovative.  Innovative features of the protocol include 
(1) a systematic approach to teaching patients how both the behavioral and cognitive pain coping skills they 
learn can be used to modify overly negative pain-related cognitions, and (2) a specific focus on helping 
patients who are prone to catastrophizing learn how to apply coping skills to the specific pain-related 
challenges associated with knee replacement surgery. Finally, studies of pain coping skills training routinely 
use self report outcome measures to assess effectiveness. Ours will be the first to include physical 
performance among our secondary measures to assess outcome, an innovative addition to outcome 
assessment. 
Innovation: Specific Aim 2 
Pain catastrophizing has been shown to mediate outcome of multidisciplinary medical treatment for chronic 
pain.52-55 The KASTpain trial will be the first to determine if pain catastrophizing plays a mediating role in the 
context of a perioperative pain coping skills training intervention. By quantifying effects as illustrated in Figure 
1, we will provide new insights into the temporal relationship of mediation effects of pain catastrophizing in 
patients receiving pain coping skills training immediately prior to, immediately after and several months 
following surgery. 
 
Approach: Specific Aim 1 
 
Trial Design  
The investigative team reached consensus on the final trial design during the R34 planning process. The 
KASTpain study will be a multi-center phase III randomized three-arm controlled trial designed to determine if 
pain coping skills training improves outcomes following primary knee arthroplasty to a greater extent than 
either an attention control arthritis education intervention or usual care. 
Outcome assessors will be blinded to group assignment and patients randomly assigned to either the coping 
strategies training or arthritis education will be blinded to experimental group assignment to the extent that they 
will not be informed which group is believed to contain the key therapeutic elements (pain coping skills). 
Patients randomly assigned to usual care will not be blinded but assessors will be blinded to group 

_____________________________________________________________________________________________________________________ 
assignment. The eligibility criteria are designed to select a study sample with a Pain Catastrophizing Scale 
score of 16 or higher and therefore at high risk for poor outcome.27-29,29,31 The primary outcome measure will be 
the WOMAC Pain scale, measured at 1 year following surgery. In addition, several secondary outcome 
measures also will be assessed (see Primary and Secondary Endpoints below). See Figure 2 below for a 
flow diagram of the planned trial.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Description of the Study Organization and Administration  
The organizational chart in Figure 3 below depicts the organization of the trial personnel. The coordinating 
center is Virginia Commonwealth University. 
Patient Screening
Baseline Assessment
Randomization
(stratified by surgeon
and site)
Ineligible or decline
Fail inclusion criteria
Meet exclusion criteria
Usual Care
Arthritis Education
Control
Pain Coping Skills
Training
1 week pre-operative assessment
1 year post-operative assessment
6 month post-operative assessment
1 week post-operative assessment
2 month post-operative assessment
End of study
Figure 2

_____________________________________________________________________________________________________________________ 
The PI will lead the trial and will chair conference calls and meetings of the Steering and Executive 
Committees (see below). The PI will also work in conjunction with the steering committee to assess study 
progress and to make modifications to the study plan when needed.  
Figure 3 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Steering Committee 
The Steering Committee is responsible for the overall direction of a study. The specific duties of the Steering 
Committee will be to: (1) Prepare the essential study documents, including the protocol, protocol amendments, 
MOOP, and data collection forms; (2) review data collection practices and procedures; 3) modify study 
procedures as appropriate; (4) make appointments to or disband various study implementation committees as 
appropriate; (5) allocate resources based on priorities of competing study demands; (6) review study progress 
in achieving goals and take necessary steps to ensure the achievement those goals; (7) review and implement 
recommendations from the DSMB; and (8) review and respond to other general advice and/or 
recommendations (e.g., from the NIAMS Program Officer or other appointees). Table 1 below lists the 
members of the steering committee. 
Table 1 Steering Committee for KASTpain Trial 
Name  
Academic Site 
Daniel L. Riddle, PhD - Chair 
VCU 
Dennis Ang, M.D. 
IUSM 
Robert E. Johnson, PhD 
VCU 
Mark Jensen, PhD 
UW 
Frank Keefe, PhD 
Duke Univ 
Khaled Saleh, M.D. 
UVA 
Kurt Kroenke, M.D. 
IUSM 
 
  
Principal
Investigator
Dan Riddle
Site Coordinators
(VCU - Riddle)
(IUPUI - Ang)
(Duke - Keefe)
(SIU - Saleh)
Statistical/Data Team
Bob Johnson.
Brain Bush
Shelby Reed
Intervention Team
Frank Keefe,
Daphne McKee
Dan Riddle
Medical Team
Khaled Saleh, MD
Dennis Ang, MD
Frank Keefe, PhD
Interventionists
(VCU)
Tim Nay
Bruce Rybarczyk
TBD for other sites
DSMB (staff to be
determined after
consultations with
NIAMS
Grant Support Staff
Brenda McFail
remaining staff to be
determined
Executive Committee
Dan Riddle
Robert E Johnson
Frank Keefe
Khaled Saleh
Dennis Ang
Jim Panagis (NIAMS)
Steering Committee
Dan Riddle
Dennis Ang
Khaled Saleh
Robert E Johnson
Frank Keefe
Mark Jensen
Kurt Kroenke
Publications
Committee
Dan Riddle
Robert Johnson
Frank Keefe
Consultants
Mark Jensen
Kurt Kroenke
Matt Bair
Shelby Reed

_____________________________________________________________________________________________________________________ 
Executive Committee  
The Executive Committee is the smaller study leadership group that guides the study’s day-to-day 
implementation and operation. This committee comprises the investigators coordinating research at each study 
site along with the biostatistician and the NIAMS program officer or representative. Table 2 lists the Executive 
Committee for the KASTpain study. 
Table 2 Executive Committee for KASTpain Trial 
 
 
 
 
Publications Committee 
This committee will plan the strategy for dissemination of the various publications resulting from the trial. The 
committee will be headed by Dr. Riddle. The committee will meet more frequently during the initial phases of 
the study to plan the publications and, in conjunction with input from other investigators involved with the study, 
begin planning a list of publications shortly after the study starts. 
 
Statistical/Data Team 
This group will work together to coordinate the data analysis and to address issues and concerns related to the 
data collection process. Dr. Johnson and Mr. Bush work closely together in the same department in the 
coordinating center (VCU) which should facilitate the rapid attention to any study related issues that impact 
data collection and storage. Dr. Reed, our health economist will work closely with Dr. Johnson during the data 
analysis phase of the study in conducting the cost analysis.  
 
Intervention Team 
This group has developed the treatment protocols to be used in the study. The team will work together to 
ensure that all interventions are applied and will conduct quality assessments of the interventions as defined in 
the MOOP. The Intervention team will be headed by Dr. Frank Keefe. 
 
 
 
Medical Team 
The medical team will address any medical concerns that arise during the study. This team will be involved 
with work by the DSMB in the unlikely event that modifications are needed to the study protocol. The team is 
made up of a Rheumatologist, a Surgeon and a Psychologist to address any potential medically related 
complication associated with the study. The team will be headed by Dr. Dennis Ang.  
 
Coordinating Center 
The roles and responsibilities of the Coordinating Center will be to: (1) train centers in all aspects of 
recruitment, retention and data capture; (2) develop and maintain the MOOP; (3) define the randomization 
scheme and ensure that all centers are properly trained to apply the scheme during the study; (4) assess the 
Name  
Academic Site 
Daniel L. Riddle, PhD - Chair 
VCU 
Robert E. Johnson, PhD 
VCU 
Frank Keefe, PhD 
Duke Univ 
Dennis Ang, M.D. 
IUSM 
Khaled Saleh, M.D. 
SIU 
Jim Panagis or designated rep. 
NIAMS 
 

_____________________________________________________________________________________________________________________ 
validity and completeness of data flow and data tracking and address issues of Center adherence concerns to 
the steering committee; (5) develop procedures for data entry error identification and error correction; (6) train 
all centers in adverse event reporting; (7) communicate all aspects of study with participating centers; (8) make 
site visits to assure adherence to the study protocol and procedures; (9) institute and assess all quality control 
procedures, generate reports for the steering and executive committees and the DSMB; and 10) distribute all 
reports and updates of policies to all centers.   
The PI will lead bi-weekly phone meetings with the site coordinators and PIs from each site as well as the 
monthly calls with the executive committee. 
 
 
Clinical Sites 
The roles and responsibilities of the Clinical Sites will be to: (1) Maintain the Site MOOP with revisions sent by 
the coordinating center; (2) Participate in site specific modifications to the study protocol related to patient 
recruitment to accommodate unique site characteristics; (3) assure that the study is conducted according to the 
protocol and the MOOP; (4) participate on the Steering Committee and other committees as appointed; (5) 
identify, recruit, screen, and enroll subjects, 6) protect the rights of all subjects; (7) obtain verbal consent during 
screening from each subject and obtain written informed consent as appropriate, from each subject; (8) 
demonstrate compliance and accountability with the study policy and procedures; (9) follow procedures 
regarding retention and forwarding of consent forms to data coordinating center; and (10) communicate any 
questions, concerns and key observations to the Principal Investigator and coordinating center.  
Because all data collected during the study will be entered into a secure website, reports related to patient 
recruitment, data completeness, and timing will be generated by the Data Management Center. These reports 
will be provided to each site on a monthly basis.  
  
 
Committee Meeting Schedules 
Teleconference and in-person meetings will be held by the various committees based on the following 
schedule: 
Steering Committee: Quarterly by phone. 
Executive Committee: Monthly by phone. 
Site Principal Investigators along with site study coordinators: Every two-weeks by phone.  
Publications Committee:  Twice a year meetings for first 2 years, then quarterly for remainder of study by 
phone. 
Statistical/Data Team: Quarterly by phone. 
Intervention Team: Quarterly by phone. 
Medical Team: Quarterly by phone. 
Investigator and consultant in-person meetings: This group will meet twice during the study. Because the team 
worked closely together during the R-34 funding period and after to develop the design and MOOP, there will 
be no meeting prior to the start of data collection. Rather, the first in-person meeting will be at approximately 
the midway point to assess study progress and make recommendations regarding any major revisions to 
assure completion of the study in the allotted time. The final meeting will be held at the end of data collection to 
review initial analyses and plan the writing of manuscripts on the final results and to plan other dissemination 
approaches. 
 

_____________________________________________________________________________________________________________________ 
 
 
Participants 
Patients will be recruited from orthopaedic surgery practices in four centers: (1) Virginia Commonwealth 
University Medical Center; (2) Duke University Medical Center; (3) Indiana University; and (4) Southern Illinois 
University. Investigators from each site along with the PI have met with participating surgeons from the 4 
centers and all have consented to participate (see support letters). Investigators at all sites have strong 
collaborative relationships with their orthopedic surgeon colleagues and, as part of our R34, have cemented 
these relationships over the last 2 years in preparation for the proposed trial. 
The three major sources of treatment variation in knee arthroplasty are surgical technique, physical therapy 
and medication usage. A variety of surgical approaches and implants are available with no clear evidence of 
superiority among the options.56 Surgeons are accustomed to conducting this surgery, for the most part, in the 
way that they were trained and to attempt to enforce standardization in surgical procedures was, in our view, 
unrealistic. In lieu of controls for surgical approach we will: (1) randomly stratify by surgeon and, (2) collect 
data from each surgeon on: (a) type of implant (i.e., cruciate retaining, posterior stabilized, rotating platform, 
patellar resurfacing (yes or no for each); (b) surgical approach (mid-vastus, sub vastus, medial parapetallar); 
and (c) use of cement (yes or no). These data will be collected for all patients and examined as potential 
covariates.  Because surgical approach will not be standardized, there is no concern for a lack of equipoise 
among participating surgeons. Physical therapy for patients following TKR, in contrast, is generally similar 
across clinics in that the goal of physical therapy is to enhance functional status via range-of-motion and 
strengthening exercise and gait and balance training. There is no evidence of a clear benefit of any single 
physical therapy approach at one year. 57 To account for the duration (dosage) of physical therapy we will 
collect data on the total number of physical therapy visits for all patients and assess the impact of number of 
visits on outcome. Regarding medication use, we will track medication use in all three arms with a 
comprehensive medication list (see MOOP) to categorize the medication profile for each patient over the 
course of the study.  
Chart abstractors blinded to treatment assignment will indicate if the patient had one or more of the following 
post-surgical complications: implant infection requiring surgery, implant failure requiring revision, implant 
loosening requiring revision, symptomatic DVT or PE, patellar dislocation or failure and knee fibrosis requiring 
manipulation. These complications typically require hospitalization or additional care and may influence 
outcome independent of the interventions being studied. Randomization will likely control for these effects, but 
we also will statistically adjust for the impact of these complications on study findings, if necessary.  Overall, 
this pragmatic approach will, in our view enhance study generalizability. 
 
Inclusion criteria will be the following: 
 
Adults 18 years of age or older and capable of providing informed consent. 
 
Diagnosis of osteoarthritis using American College of Rheumatology (ACR) criteria of moderate to 
severe knee OA58 and function limiting pain as determined by the patients’ orthopaedic surgeons. 
 
Scheduled for an elective unilateral total knee arthroplasty no sooner than 2 weeks or later than 8 
weeks from the time of recruitment. 
 
Score of ≥ 16 on the Pain Catastrophizing Scale and ≥ 5 on the WOMAC Pain scale. 
 
Able to read and speak English. 
 
Exclusion criteria will be the following: 
 Scheduled for revision arthroplasty surgery. 
 Unable to or declines consent for study participation. 

_____________________________________________________________________________________________________________________ 
 Self-reported diagnosis of inflammatory arthritis (i.e. rheumatoid arthritis, psoriatic arthritis, systemic 
lupus erythematosis, ankylosing spondylitis). 
 Arthroplasty scheduled because of a fracture, malignancy or an infection. 
 Scheduled for bilateral arthroplasty surgery.  
 Scheduled for unicompartmental arthroplasty. 
 Self reported plan to undergo hip or knee arthroplasty within one year after current knee arthroplasty.  
 Presence of severe depression (20 or higher) using the PHQ-8 depression screener.59,60 
Although it is possible that depressive symptoms could interfere with treatment efficacy, it is also possible that 
those with depressive symptoms might benefit more from the treatment than those who are not depressed, 
given that the intervention teaches skills that can help in the treatment of depression.  By excluding only the 
participants with severe depressive symptoms, and including patients with other levels of depressive 
symptoms, generalizability will be enhanced and we will be able to determine if the intervention is more or less 
effective among persons with depressive symptoms, relative to non-depressed persons. In our pilot study of 
112 knee arthroplasty patients with high pain catastrophizing as defined in our trial, a total of 3 patients (2.7%) 
had PHQ scores of 20 or higher. Depressive symptoms will be examined as a potential moderator of treatment 
effect in the analysis.  
Other exclusion criteria were selected to reduce the risk of confounding in the trial. For example, patients 
receiving revision surgery have poorer outcomes as compared to patients undergoing primary knee 
arthroplasty.56 Screening will be conducted via telephone by study staff after the patient has consented for 
surgery.  
 
 
Randomization and Blinding 
Participants who meet study inclusion criteria and consent to participate will be stratified by orthopaedic 
surgeon and randomized in permuted blocks of 3, one to each study group, to ensure that patients from each 
participating physician and site have an equal chance of being randomized to one of the 3 groups. Given that 
we will have 30 orthopaedic surgeons participating in the study (see Table 5 below), this approach will control 
for temporal and clustering effects resulting from single surgeons having imbalances in the numbers of patients 
in each treatment group over time. Assignment to one of the 3 groups will be accomplished with a computer 
generated table of random numbers created by the biostatistician and provided to the study coordinators at 
each site via a secure website. After collecting baseline data, each site’s study coordinator will conduct 
treatment allocation by use of the study web site, allowing the treating surgeon and the follow-up data 
collectors (site coordinators and research assistants) to be blinded. We will instruct all surgeons of the 
importance of avoiding study contamination by not querying patients about study interventions. Surgeons also 
will be asked to report if they became aware of group assignment during the study. These data will be tracked 
and reported at the end of the study.  
All data collected at each site will be obtained by data collectors who are blinded to group allocation. This will 
be accomplished by assigning patients to one of the three treatment groups using a secure website and then 
providing patients with treatment allocation information in random number matched pre-sealed opaque 
envelopes. Patients will be instructed to open envelopes once they return home and they will be asked not to 
mention their group assignment to the data collectors. Information in the envelopes will inform patients about 
group assignment and will instruct patients to contact site PIs if they have any questions about the treatment to 
which they have been assigned. Because site PIs will not be collecting data from patients, we will optimize the 
likelihood of keeping data collectors blinded to group allocation during the course of study.  

_____________________________________________________________________________________________________________________ 
 
 
Interventions 
 
 
Pain Coping Skills Training 
Patients assigned to pain coping skills training will have 8 sessions delivered by one of the sites clinical 
psychologists with experience treating patients with pain. There will be an initial in-person session 
approximately 1 month prior to surgery, six weekly telephone-based sessions with three prior to surgery and 
three during the 3 weeks following surgery, and one final in-person session approximately 1 month following 
surgery. Eight skills training sessions delivered over a 2 month period has been shown to be effective in 
several behavioral trials.44-50 Use of telephone-based sessions is a new development in behavioral research 
and one which we have prior experience. It offers a cost-effective and practical approach for patients who have 
difficulty with mobility and travel.61,62  
The pain coping skills training intervention was developed as part of our R34 funding and is based on 
information gathered in previous studies of chronic and arthritic pain by Keefe, Jensen and others,45,54,55,63-68 as 
well as our pilot study.69 The intervention is designed to modify coping strategies found to be related to pain 
and disability (please see the clinician training manual and the corresponding patient manual in the MOOP).  
The final protocol was based upon an extensive review of the literature, intensive discussions among the 
investigators, input from international experts working in the field of psychosocial interventions and pain 
catastrophizing, and our clinical experience working with OA patients who are high catastrophizers. There was 
consensus among all involved on three points: (1) that an overly narrow protocol, i.e. a simple attempt to use 
cognitive restructuring to alter catastrophizing only was unlikely to work because it would not examine the 
broader context in which catastrophizing cognitions occur for these patients; (2) that the CST protocol should 
not be as broad in scope or as intensive as comprehensive cognitive-behavioral therapy (CBT) interventions 
for pain; and (3) that CST should be used since it is the only intervention to date that has been shown in 
controlled studies to reduce both pain catastrophizing and pain.   
The protocol to be tested is consistent with these three points.  First, it includes training not only in cognitive 
restructuring but also a variety of skills that provide patients with opportunities to observe the impact of coping 
skills on changes in overly negative pain-related cognitions.  Second, the CST protocol is neither as broad in 
scope nor is as intense as typical CBT interventions for general chronic pain.  Rather, each of the skills 
included in our CST protocol was chosen specifically because it provides a potentially potent means of helping 
patients identify and change their catastrophic pain-related thoughts.  We designed this CST protocol so that a 
key component of training for each of the skills is teaching patients how that they can use that skill to identify 
and reduce their catastrophizing.   For example, patients will be trained in the coping skill “activity-rest cycling” 
and be taught how to monitor and change negative cognitions that arise as they apply this skill in daily pain-
related situations. Application of this skill will help patients change from a cognition such as "I can't go for a 
walk around the neighborhood with my partner " to "I can go for walks if I break the walk up into periods of 
moderate activity followed by short rest breaks."   Another example; patients will be trained in the coping skill of 
relaxation training and encouraged to identify and change negative cognitions as they apply this skill.  For 
instance, prior to training in this skill a patient having a pain flare might think "I just can't relax when I am 
hurting" whereas after training they can learn to identify and then replace this thought with the thought "I have 
learned ways to relax and have used them during severe pain episodes in the past."   
Protocol Description:  Table 3 highlights the key elements of the CST protocol.  The CST protocol will: (1) 
provide a rationale for the coping skills intervention; (2) train patients in cognitive restructuring as well as a 
variety of skills that provide patients with opportunities to observe the impact of coping skills on changes in 
overly negative pain-related cognitions; and (3) provide training in strategies for enhancing maintenance of 
gain following treatment.  Rationale: To introduce the training, a simplified version of Melzack and Wall's gate 
control model of pain will be used to help patients understand that pain is a complex experience affected by 

_____________________________________________________________________________________________________________________ 
thoughts, feelings and behaviors.70  Pain coping strategies will be described as skills that can be mastered 
through home practice. Training in coping skills: Cognitive-restructuring will be used to help the patient 
recognize the relationships between thoughts, feelings and behavior.71  These techniques will teach them to 
identify irrational, maladaptive thoughts and to replace these with alternative, rational, reassuring and adaptive 
thoughts.  A self-instructional training intervention developed by Turk and colleagues72 will be used to help the 
patient use calming self-statements when dealing with severe pain. Activity-rest cycling and pleasant activity 
scheduling73-75 will be used to reduce pain and enable patients to pace and increase their activity level.  In 
activity-rest cycling, patients identify activities in which they overexert themselves (e.g., housework or 
shopping), learn to break those up into periods of activity and rest (e.g., 45 minutes of housework followed by 
10 minutes of rest), and gradually increase their activity level as they decrease rest.  Patients will identify 
activities they enjoy such as reading, doing crafts and hobbies, or visiting friends and then set and record 
weekly activity goals. Patients also will be trained in three attention diversion methods: relaxation, imagery, and 
distraction.  Relaxation training, using a protocol and relaxation tape described by Surwit,76 will involve 
concentrating on muscle tension signals and using them as cues to relax.  Imagery will be taught as an adjunct 
to relaxation.77  Patients will practice using pleasant imagery and changing from one image to another.  
Distraction techniques will include focusing on physical or auditory stimuli.77 Maintenance Enhancement: Using 
relapse prevention methods, each patient will develop a written maintenance plan that includes the list of pain 
coping skills learned during the study, potential high risk situations, early warning signs of setbacks, and plans 
about how the patient might apply these skills in dealing with future setbacks and challenges.  
Table 3 Key Elements of the CST Protocol 
 
 
 
 
 
Use of 
clinical 
psychologists to deliver the skills training may limit generalizability of our findings to settings with adequately 
trained psychologists. Because evidence is lacking on the use of lesser trained practitioners and because, in 
our experience, this patient population is particularly challenging given their higher levels of pain 
catastrophizing, we believe it is important to test the intervention using practitioners with advanced skills. 
However, we will plan implementation studies with non-psychologist practitioners if the results indicate that the 
intervention is effective. 
  
 
Arthritis Education Comparison Condition 
Patients randomly assigned to Arthritis Education, a comparison condition that will control for participation in a 
trial, time and therapist attention, will receive detailed educational information from a nurse educator about OA 
and its treatment. Nurse educators have similar levels of clinical experience as clinical psychologists, which will 
assist in making the argument that it is the content of the interventions and not the delivery of these 
interventions that we will be testing in the trial. The arthritis education sessions will use a presentation and 
discussion format similar to that originally described by Lorig for arthritis education.78-80 The clinician and 
patient manuals were developed as part of our R34 funding (see MOOP). Figures and discussion sessions will 
present information on the nature of arthritis, what to expect following knee arthroplasty, treatment of 
osteoarthritis, the role of exercise, joint protection and making future treatment decisions.  
Training Objective 
Coping Skill Training Methods 
Altering Cognitions to Change Pain 
Catastrophizing  
Cognitive Restructuring, Self-Instructional Training 
Altering Activity Patterns To Change Pain 
Catastrophizing 
Activity-Rest Cycling, Goal Setting 
Using Attention Diversion to Change Pain 
Catastrophizing  
Relaxation Training, Imagery, Distraction 
Enhancing Maintenance  
Relapse Prevention Training 
 

_____________________________________________________________________________________________________________________ 
This general approach to an arthritis education comparison condition has been used successfully in many 
behavioral studies and in several trials conducted by Keefe and Jensen.44-50,55 Use of an education comparison 
condition enhances the scientific credibility of the study by testing whether the "pain coping" component of the 
experimental intervention effectively reduces pain and improves function over that seen in patients who receive 
a similar dose of time and attention from a health professional, but no specific pain coping skills.  
 
 
Usual Care 
Because the standard of care in joint arthroplasty includes no treatment directed toward poor pain coping, we 
have added a “usual care” group to determine real world effects of pain coping skills. Patients in the usual care 
group will only receive care that they would have routinely received had they not been entered in the study. 
 
 
Economic Evaluation 
Four types of information will be collected throughout the study for use in the economic evaluation: (1) all-
cause medical resource use; (2) patient time; (3) health utilities; and (4) resources required to provide the 
coping skills training, arthritis education and usual care. We will collect information on all-cause medical 
resource use including hospitalizations, emergency department and urgent care visits, orthopedic-related 
procedures, medications for pain and/or inflammation, and outpatient visits, including sessions for physical and 
occupational therapy.  This information will be ascertained via patient self-report and supplemented with 
medical records abstraction.  To improve the accuracy of patient self-report, patient diaries will be designed to 
track medical resource use to record their estimates of time spent receiving the interventions, adhering to 
treatment recommendations (e.g. physical therapy), and employing coping skills.81 Validity of patient diaries of 
medical service utilization is generally supported, particularly when instructions to patients are clear.82,83 To 
incorporate potential differences in health-related quality of life experienced by patients in the three study arms 
into the cost-effectiveness analysis, we will measure health utilities using the 5-level EQ-5D (5L EQ-5D).84 
According to the EuroQoL group, preference weights for the 5L EQ-5D should be available by the end of 2012 
(EuroQol Group Executive Office - personal communication). Finally, we will prospectively collect information 
on time spent by clinical psychologists and nurse educators and other individuals involved with the delivery of 
the study interventions as a basis for estimating intervention costs.    
In accordance with recommendations for economic evaluation in health care, we will value costs from the 
societal perspective.85 We will use standard cost assignment methods to estimate direct medical costs. To 
assign costs for inpatient care, we will assign Medicare diagnosis-related groups (DRG) codes and 
corresponding reimbursement rates, adjusted for differences in length of stay reported for patients in the 
study.86,87 Medication costs will be based on the published average wholesale price (AWP) minus 16%.88 
Indirect costs associated with patient time will be valued using the average hourly wage in the US ($20.90, 
May 2009).89 To estimate costs associated with the pain coping skills and arthritis education, we will apply a 
costing tool that we designed specifically to estimate costs associated with patient-centered interventions 
(5R01NR011873-02, manuscript in appendix 7). The tool applies scientifically-sound economic principles to 
assign costs to personnel, facilities, equipment, supplies, patient incentives and miscellaneous items.  
 
 
Steps to Enhance Treatment Fidelity and Reduce Potential Biases  
Because multiple sites will participate and increase the risk of bias due to differing approaches in applying the 
interventions, the research team will take a number of steps to ensure that the treatment protocols for coping 
skills training as well as arthritis education are delivered uniformly by all treatment providers involved in the 
study. First, all pain coping skills training will be implemented by clinical psychologists with experience treating 
patients with chronic pain. Second, all psychologists who participate in the study will receive coping skills 
training in workshops facilitated by Dr. Keefe and his team at Duke University.  Experienced nurse educators 
will all be trained by Dr. Riddle to provide the arthritis education. Third, all psychologists and nurse educators 

_____________________________________________________________________________________________________________________ 
will be provided with detailed treatment manuals (as developed in the MOOP), and the treatment strategies will 
be taught through didactic instruction, taped illustrations of techniques from model cases, and role-play of 
common scenarios. Fourth, we will institute several “best practices” to enhance and monitor treatment fidelity 
of the pain coping skills training and arthritis education protocols which include: (1) careful attention to the 
treatment manuals; (2) intensive training onsite and at Duke University; (3) “real-life” enactment of treatment 
skills during training, and (4) on-line documentation of treatment delivery. Finally to provide supervision, all 
sessions for both groups will be audiotaped. These tapes will be reviewed in supervision sessions on a regular 
basis to ensure that the treatment manuals are being followed. Supervisors will provide feedback based on the 
review of these tapes. Remedial training will be provided to those clinicians who deviate from established 
protocol. 
Treatment adherence, therapist competence and treatment credibility ratings will be collected from the two 
active intervention groups. Adherence refers to the extent to which a therapist uses interventions prescribed by 
a protocol. Therapist competence refers to the extent to which the protocol is delivered in a manner that is 
skilled and sensitive to patients’ needs. Ratings of treatment adherence will be made by Drs. Keefe and 
Jensen (and by Dr. Riddle for the arthritis education arm) for a random selection of 10% of the sessions for 
each of the treatment conditions.90  Protocol adherence rating sheets developed for each session will be used 
with satisfactory adherence defined as 90% or more of the maximum possible score on the adherence rating 
scale.  Ratings of therapists' competence will be made using a 1 to 5 scale with satisfactory competence 
defines as an average of 4.0 or higher. Following the first treatment session, patients will complete a treatment 
credibility questionnaire developed by Devilly and Borkovec.91   
With regard to study design, we will ensure the same treatment dose within and across treatment conditions 
(Pain Coping Skills Training vs Arthritis Education). We will monitor session attendance for coping skills 
training and arthritis education using a diary log with participant ID numbers and session dates to track 
percentage of attendance and to account for absenteeism and reasons for missed sessions. We will make 
every effort to deliver the full treatment, but we expect some variation in treatment delivery dose as well as 
treatment drop-out. Reasons for attrition will be assessed with an open-ended question for enrolled participants 
who withdraw.  Drop-out reasons will be categorized and then judged by independent raters.  Comparisons 
between the treatment conditions in drop-out rates will be made, and these rates will be included as covariates 
in the planned analyses if significant between-group differences emerge. 
Loss to follow-up is always a threat in longitudinal studies. The following strategies will be employed to 
minimize loss to follow-up: (1) we will use up to 8 phone attempts to contact participants to schedule their post-
treatment assessments; (2) we will obtain alternative phone contact information from each participant; (3) if we 
fail to contact a  participant during follow-up phone contacts, despite multiple phone attempts, we will mail a 
reminder letter; (4) participants will receive up to $150 remuneration for study participation and this 
remuneration will distributed throughout the study period to be commensurate with study demands; and (5) we 
inflated our sample size by 20% to account for possible attrition. 
Additional retention strategies will be employed in the study to reduce loss to follow-up as much as possible. 
For example, study coordinators will personally meet each patient enrolled in the study to develop rapport with 
each patient. The study website developed by the data coordinating center will provide study coordinators at 
each site with red-flag notices when patients miss their scheduled appointment dates by more than 48 hours. 
Study coordinators will be required to contact patients with missing data within 24 hours of receiving a red-flag 
notice. The PI will receive weekly reports from the data coordinating center so that the study investigators can 
discuss recruitment and retention during bi-weekly conference calls.  
Preliminary Studies 

_____________________________________________________________________________________________________________________ 
Riddle has led and completed two published studies of the relationship between psychological distress and 
outcome following knee arthroplasty. The first was a secondary analysis of a cohort study of 952 patients and 
was published in 2007.92 Our findings suggested that surrogate measures of general psychological distress 
(like the mental health score of the SF-36) did not provide adequate fidelity and that more precise measures of 
specific psychological states and disorders were necessary.  
To test this hypothesis a second study was undertaken to determine if more specific measures of 
psychological distress (i.e., depression, anxiety, self-efficacy, fear of movement, pain catastrophizing) predict 
pain and functional outcomes following knee arthroplasty.29 After adjusting for confounding factors, pain 
catastrophizing was the only consistently strong psychological predictor of poor WOMAC Pain outcome (Odds 
ratio  = 2.7, 95%CI=1.2, 6.1). We found that 60% of patients with high pain catastrophizing had a poor 
outcome, (defined as a WOMAC Pain change score of <50% from baseline to 6 months post surgery) as 
compared to 30% of patients with low catastrophizing who had poor outcome. Other studies have reported 
similarly strong findings indicating that pain catastrophizing predicts pain and function outcome following knee 
arthroplasty.27,28,30,31 
 
Pilot Intervention Study 
The research team recently completed a quasi-experimental study of the efficacy of the proposed pain coping 
skills intervention.69 We recruited 18 knee arthroplasty patients from two sites (Duke University and Virginia 
Commonwealth University) to participate. All patients met the inclusion criteria as defined in our proposed trial 
and received the pain coping skills training intervention. WOMAC Pain and Disability scores and PCS scores 
were collected prior to surgery and 2 months following surgery. Data from patients receiving pain coping skills 
training were compared to a historical cohort of 45 patients who also received knee arthroplasty and had high 
pain catastrophizing (≥ 16 on PCS), but received no pain coping skills training. ANCOVA adjusting for baseline 
scores was used to compare the patients in the treatment group to the historical cohort. The Group (coping 
skills training vs usual care) X Time (pre-op vs follow-up) interaction was used to estimate the magnitude and 
significance of the treatment effect.  
Patients in the pain coping skills group demonstrated a mean improvement in WOMAC Pain scores of 6.9 (sd 
= 4.7) points while patients in the historical cohort achieved a mean improvement of 2.6 (sd = 4.8) points. 
Differences among groups were highly significant with effect sizes ranging from .71 to .96. for WOMAC 
Disability, WOMAC Pain and Pain Catastrophizing. 
Respondent burden was assessed by asking participants to complete a 16-item questionnaire (2 items for 
each coping skill) that assessed the extent to which each skill was helpful and how frequently the skills were 
used. Patients rated each skill as being somewhat to extremely helpful and patients indicated they used each 
skill at least weekly to more than once per day. These data suggest that patients found the skills to be 
therapeutic and useful during their recovery. 
In summary, our preliminary work and the work of others27,28,31,39 strongly suggest that: (1) pain catastrophizing 
is a key psychological variable that adversely impacts pain and functional outcomes in patients following knee 
arthroplasty; (2) our proposed intervention has strong potential for producing clinically important improvements 
in self-reported pain and functional status in patients who are at high risk for poor outcome; and (3) the 
feasibility of the intervention is high and can be delivered efficiently in multiple sites.  
Pilot Physical Performance Battery Study 
We undertook a second pilot study to determine the feasibility of using a well defined physical performance 
battery for patients following knee arthroplasty. Associations between self-report and performance measures 
are moderate, on the order of r = .5, suggesting they measure different patient attributes.93-97  

_____________________________________________________________________________________________________________________ 
Because there is no agreed upon standard set of performance-based measures for patients with knee 
arthroplasty, we chose to pilot a six-minute walk test a measure that is reliable and captures changes in 
distance walked and pain perceived throughout the recovery period.93,94,98. The Short Physical Performance 
Battery (SPPB) combines two simple balance tests a 4-meter walk test and a repeated chair stand test into 
one summated score.  The SPPB has been studied extensively and found to be significantly reduced in 
persons with knee arthritis as compared to healthy age-matched persons99 and is responsive to changes 
following interventions designed to improve mobility.100,101  
We recruited a consecutive series of 10 patients 1 year following knee arthroplasty to determine if the SPPB 
and the six minute walk test would be well tolerated. In addition, we were concerned about possible ceiling 
effects on the SPPB which can occur with high functioning elderly persons.102 SPPB total scores range from 0 
to 12. The mean score on the SPPB summary scale for the patients was 8.5 (sd = 2.3) and ranged from 3 to 
11. We concluded that the SPPB and the 6-minute walk test are well tolerated by patients receiving knee 
arthroplasty and that some individual tests comprising the SPPB will likely demonstrate ceiling effects. We will 
therefore use the composite SPPB score and a time-based calculation of the composite SPPB score103 in 
addition to the 6-minute walk test. 
Primary and Secondary Outcome Measures and Endpoints   
Participants from all three arms will be evaluated by an assessor who is blinded to group allocation at baseline, 
1 week prior, and 1 week after, 2 months, 6 months and 1 year after surgery. The baseline assessment will 
include age, gender, comorbidity14,104, education and occupation, current medications, mental healthcare 
received and a variety of pain and psychological characteristics including depression, anxiety, pain coping etc. 
Follow-up outcomes will include measures of pain, function, catastrophizing and depression. (see MOOP in 
appendix for a complete description). 
The primary outcome measure and endpoint will be the WOMAC Pain scale measured 1 year following knee 
arthroplasty.105-109 The WOMAC has been studied extensively and its scales have been shown to be reliable 
and valid for quantifying the extent of both pain and disability in patients undergoing knee arthroplasty.16,110,111 
Secondary outcome measures will be the WOMAC Disability scale, Pain Catastrophizing Scale (PCS),112-114 a 
verbal pain rating scale,115,116 and a patient global rating of change scale measured on a numerical rating scale 
from -5 (vastly worse) to +5 (completely recovered) and measured 2 months, 6 months and 1 year post-
surgery.117-119 The timeframes were chosen because the trajectory of recovery following knee arthroplasty is 
non-linear and we want to track changes associated with the intervention during the course of the study.10,13,94  
Two performance-based measures, the 6-minute walk test 93,98 and the Short Physical Performance Battery will 
be assessed at baseline and 1 year post-surgery.120 Routine follow-up visits are typically scheduled with the 
surgeon at 12 months following surgery. Planning follow-up measures to coincide with routine patient visits to 
their surgeon or other provider will be a cost-effective and clinically feasible way of collecting follow-up data 
with minimal burden. All sites will have the space necessary to conduct the performance-based tests. This is 
the first study of a pain coping skills training intervention that has used performance-based measures to 
assess efficacy. This battery of primary and secondary outcomes addresses the key domains of outcomes 
recommended by IMMPACT, a consensus based group of experts in the area of pain treatment 
outcomes.121,122 
 
 
Sample Size Estimations 
The primary endpoint will be the WOMAC Pain score at 1 year. Changes of 2 or more points in the 20 point 
WOMAC Pain scale indicate clinically important differences between individual patients.123-126 We powered our 
study to detect a difference of at least 2 points between the pain coping skills group and the arthritis education 
group. Our pilot study showed a larger difference of 4.2 points (with an effect size of .74) between the coping 
skills group and the usual care group two months following surgery. We will use a more conservative treatment 

_____________________________________________________________________________________________________________________ 
effect of 2 WOMAC Pain points for coping skills training for three reasons. First, our pilot study used a quasi-
experimental design which may overestimate treatment effects because of non-randomization. Second, 
estimates were based on comparisons to usual care, and we suspect that some therapeutic benefit will be 
experienced by the arthritis education group. Third, these data represent only short-term changes following 
surgery and most patients continue to improve up to a year following surgery.9,14  
Using a two-sided two group 0.05-level t-test of differences in means and assuming the intervention difference 
minus the arthritis education control difference is at least 2.0 WOMAC Pain points, a sample size of 107 in 
each group will have 91% power to detect this difference, assuming that the common standard deviation is 
4.34 (based on pilot work described earlier). This corresponds to an effect size of 0.46 which is consistent with 
the effect of other behavioral interventions for knee arthritis.127-129 This sample size also adequately powers the 
study to detect a 20% difference between groups in the number of patients with a 50% or greater 
improvements in WOMAC pain relative to baseline scores. 9,10,12-15,130 This effect will be equivalent to an odds 
ratio of 2.25 and is equivalent to a Numbers Needed to Treat (NNT) of 5 which is indicative of an effective 
intervention.131 The revised CONSORT statement endorses use of indexes such as number needed to treat.132  
Thus, the total required sample size is 321 (107 patients per arm) for the planned 3-arm trial. Based on our 
pilot study, we expect 5% attrition due to early drop-out resulting from cancelled surgery. Patients who undergo 
surgery and drop out due to lack of interest, unrelated medical illness or loss of follow-up also will be included 
in the intent to treat analysis. Our pilot study of 18 patients suggests this number will be on the order of 10%, 
although this estimate is likely to be low because the pilot study was only 2 months in duration. Our previous 
work with similar types of patients suggests that loss to follow-up will likely be closer to 20% one year following 
surgery.14,29 Therefore, 402 patients (134 patients per study arm) will need to be enrolled in the trial (321+64 
due to loss of follow-up+17 due to cancelled surgery). A total of 2,100 patients will need to be screened 
because our pilot studies indicated that approximately 19% of the screened sample will actually participate (ie. 
they will meet all inclusion and exclusion criteria AND provide consent for the study). Stratification by surgeon 
and by site is expected to reduce outcome variability and thereby increase power. 
 
 
Data Analysis 
Intention to treat (ITT) will be the primary approach for all analyses and, depending on the pattern of missing 
data (missing at random, completely at random or not missing at random), multiple imputation using SAS 
StAT/MI methods will be used to impute values for those lost to follow-up.133 In addition, we will compare the 
ITT analysis to the results for patients who actually undergo surgery to determine if undergoing surgery affects 
the findings. For the primary analysis, the effect of treatment will be assessed using linear mixed models with 
time as a repeated factor. The model will account for correlation over time within participants, correlations 
within clinics, surgeons, and baseline covariates. Surgical approach, complications, medication and physical 
therapy use will be assessed for potential effects. 
Estimates of the effect of pain coping skills training will be obtained by constructing linear contrasts to compare 
the mean change in outcome from baseline to each of the key time points (2 months, 6 months and 1 year) 
between the pain coping skills group and the two control groups, with adjustment for the other variables. 
Analyses of the secondary outcome variables will be conducted using a similar approach. For the analyses 
using dichotomous outcomes of ≥50% improvement at 6 months and 12 months, generalized linear models 
with logistic regression will be used to compare the proportion of patients with ≥50% improvement after 
adjustment for baseline data.  
Our study is powered to detect clinically important differences in WOMAC Pain scores among treatment 
groups. As an additional secondary analysis, we also will examine the effects of potential moderators. 
Moderators are baseline characteristics that predict treatment effects.134  Additional psychosocial issues may 
influence treatment effects in knee arthroplasty patients with high levels of pain catastrophizing. Potential 

_____________________________________________________________________________________________________________________ 
moderators for patients with knee arthroplasty who may particularly benefit from pain coping skills training are 
the following: expectations prior to surgery135-137, self efficacy138,139, extent of social support9,140 and 
depression.27 Recent evidence suggests that psychological states of depression, low expectations for recovery 
from surgery, poor self-efficacy and reduced social support increase risk of poor outcome following surgery, 
and may therefore modify the effects of pain coping skills training. Because our study is not powered to test for 
these potential moderators, they will be assessed only for the primary outcome of WOMAC Pain at 1 year. This 
analysis will be performed by including a three-way Moderator X Treatment group X Time interaction term in 
the mixed models analyses.  It is our intent to assess whether these variables independently predict those 
patients who are more likely to respond to pain coping skills training versus arthritis education or usual care. 
Pain coping skills training emphasizes pain coping strategies, unlike usual care or arthritis education and 
because of this emphasis, we suspected that coping strategies training would be particularly effective in 
patients with less healthy psychosocial features. Knowing whether any of these potential moderators actually 
predict response to treatment will aid in better identifying individuals who are more likely to respond to the 
intervention.  
 
 
Cost Analysis 
We will conduct a cost analysis to compare mean total costs incurred over the one year follow-up period in the 
KASTpain study between patients randomized to coping skills training vs. arthritis care (and vs. usual care).  
We will compare each component (medical costs and indirect costs) and estimate intervention costs. All three 
components will comprise total costs which will also be compared. Total costs, from the societal perspective, 
will consist of direct medical costs, intervention-related costs and indirect costs. From the health care system 
(or payer) perspective, indirect costs will be excluded. Sensitivity analyses will be performed to evaluate the 
impact of scaling up the intervention (i.e. more patients per session; fixed costs allocated over more patients) 
and methodological choices for cost assignment.141,142  
 
 
Cost-Effectiveness Analysis 
The incremental cost effectiveness ratio (ICER) will be calculated as the difference in the mean cost per patient 
between study arms divided by the difference in estimated quality-adjusted life-years (QALYS).  Mean costs 
will be estimated as described above. Quality-adjusted life-years will be estimated using utility estimates 
derived from the EQ-5D.  Because the interventions represent fixed-, one-time costs while the benefits of the 
interventions may last beyond the one year follow-up period in the KASTpain study, we will conduct sensitivity 
analyses that extrapolate differences in utilities measured at the end of follow-up over 3, 5, and 10 years, 
assuming that the interventions do not differentially impact survival.  If we observe statistically significant 
differences in costs (not including intervention costs) between treatment arms at 12 months, we will extrapolate 
treatment-specific cost estimates over 3, 5, and 10 years, consistent with the time period for QALYs. We will 
evaluate uncertainty by estimating 95% CIs for estimates of costs, QALYs and measures of cost-effectiveness 
(i.e. ICERs or net health benefits143) using nonparametric bootstrapping.141,142 
 
 
Timetable and Milestone Plan  
The milestone plan is as follows: 
 
 
Enrollment of the first subject: Prior to enrolling the first subject, all sites will be required to complete IRB 
approval procedures and interview, hire and train research staff including the clinical psychologists and nurse 
educators. All study staff will be required to complete training in the study protocol as described in the MOOP 
and will also require time to develop working relationships with orthopaedic surgery staff in preparation for 
patient recruitment and retention. Clinical psychologist training will require travel to Duke University while the 
PI will travel to each site to train the nurse educators. We expect to have all IRB, hiring and training procedures 

_____________________________________________________________________________________________________________________ 
completed and should be fully prepared to begin study recruitment within 6 months of the beginning of the 
study. Assuming that the study will begin on April 1, 2012, the first subject will be recruited by October 1, 2012.  
 
 
25%, 50%, 75% and 100% enrollment projections: We expect enrollment for these various thresholds to 
occur by the following time periods listed on Table 4 below. The recruitment period will require, at maximum, a 
total of 3 years.  
 
Table 4 Summary of Recruitment Goals 
 Completion of data collection time period: We will complete data 
collection one year following recruitment of the final subject 
which will be October 1 of 2016. 
 
The flow of the study over the course of the 5-year study period 
is summarized in figure 4 below.  
 
 
 
Completion of primary and secondary data analyses: We estimate that analyses of primary and secondary 
endpoints will be completed by February of 2017. 
 
 
Completion of final study report: We plan to complete the final study report at the end of the grant 
funding period during the month of April of 2017. 
We expect subject enrollment to require 36 months.  This estimate assumes that a total of 100 or 101 subjects 
will be enrolled at each site (n=4 sites). Our sample size estimations based on our pilot studies (see Sample 
Size Estimation Section above) indicated that we would need to screen a total of 2100 patients to successfully 
recruit the requisite number of 402 patients. Table 5 below indicates that approximately 1,768 patients undergo 
primary knee arthroplasty for OA at the four sites each year for a total of 5,305 patients in a 3 year period. We 
would need to screen approximately 40% of the total sample of patients from each site to meet our recruitment 
goals and we believe this to be realistic and feasible. Every attempt will be made to recruit the requisite 
number of patients from each site, so that each site is equally represented in the analysis. However, if one or 
more sites have difficulty meeting recruitment goals, the large number of total patients in the four sites should 
allow us the flexibility to recruit additional patients from sites that are seeing more patients. Because we have 
been working with the sites for two years as part of our R34 development, we do not expect sites to drop out or 
to have problems with recruitment. However, we have recruited two additional sites (see letters attached) to 
participate should we need to recruit additional patients. The duration of the clinical trial is estimated to be 5 
years (See Figure 4). 
PCST 
Educational Control 
Screening 
BASELIN
  0               1                  2                3                    4                 5            
Years 
E 
N 
D 
  
O 
F 
 
S 
T 
U 
D
Y 
S 
C 
R 
E 
E 
N 
I 
N
G 
B 
A 
S 
E 
L 
I 
N 
E 
Usual Care 
Figure 4 
SURGERY 
Recruitment Goal 
(% of target 
sample recruited) 
Estimated 
Date of  
Completion 
25% 
July 1, 2013 
50% 
April 1, 2014 
75% 
Jan 1, 2015 
100% 
Oct 1, 2015 
 

_____________________________________________________________________________________________________________________ 
 
 
 
 
 
 
Data Coordinating Center  
All data collection services will be coordinated 
through our Department of Biostatistics Data 
Management Group (DMG), housed in the 
Department of Biostatistics at Virginia 
Commonwealth University. This center 
provides state-of-the-art data collection, 
management, reporting, and analysis services to Virginia Commonwealth University’s clinical and translational 
researchers. DMG will provide secure data services for all aspects of data gathering including web based data 
form development for data collection, reminders and completion reports for data collectors at each site and for 
the executive committee, electronic data acquisition, server storage repository, randomization procedures for 
each site, study staff entry of performance data and tracking of visit data (including no-shows and dropouts) for 
clinicians providing the interventions. The Biostatistician will work closely with the Director of the DMG to 
assure a seamless, sound and secure process of data collection, storage and analysis.  
The web and database servers will reside on centralized Virginia Commonwealth University servers behind the 
University’s firewall.  Web-accessible systems will be protected by appropriate security measures, and utilize 
Secure Sockets Layer (SSL) encryption for transport security.  Data storage will be centralized, with regular off-
site backups performed by trained IT personnel.  Only the investigators and other approved personnel will have 
access to study data, at a level commensurate with their responsibilities.  Appropriate consideration will be 
given to subject’s identifiable information. 
In addition to the above safeguards, VCU employs a network Intrusion Prevention System (IPS) that analyzes 
data packets on the networks for known signatures of probes, intrusion attempts, IP spoofing and other 
suspicious activities. System event logs from network devices and host applications are reported to Cisco 
Security Monitoring, Analysis, and Response System (MARS) to improve threat identification, mitigation 
responses, and compliance. 
Periodic and ad-hoc reporting will be utilized to show subject recruitment and retention data stratified by site.  
Automated email agents will electronically notify site staff and investigators of upcoming and overdue subject 
follow-ups.  Upon request, the data manger will provide de-identified data in a form agreeable to the 
biostatistician.  In addition, the DMG will provide timely troubleshooting assistance via phone and email and 
answer inquiries from research staff and investigators. The investigators will develop a User’s Guide to aid the 
study staff with data management tasks should the study be funded. 
 
Approach: Specific Aim 2 
We will collect Pain Catastrophizing Scale, WOMAC Pain and Disability Scale and a verbal pain rating scale 
scores on all patients at six time points (4 to 6 weeks prior to surgery, 1 week prior to surgery, 1 week following 
surgery, 2 and 6 months following surgery and 1 year following surgery). Our rationale is that we want to 
capture the short- and intermediate-term temporal progression of changes in catastrophizing prior to and 
following treatment to describe changes in mediation over time. The primary outcome measure will be the 
WOMAC Pain scale, collected at all assessment points. The independent variable will be treatment condition 
(Pain Coping Skills Training vs Arthritis Education vs usual care). (Figure 1)  
Table 5 Estimated Sample Size at Participating Sites                 
Clinic 
site 
# of  
Surgeons 
Primary 
TKAs during 
3 year 
recruitment 
period 
Estimated 
number 
eligible and 
consenting  
Total 
needed 
for 
study 
VCU 
3 
865 
164 
100 
SIU 
12 
2210 
420 
101 
IU 
7 
780 
148 
100 
Duke 
8 
1450 
276  
101 
Totals 
30 
5305 
1008 
402 
 

_____________________________________________________________________________________________________________________ 
Our hypothesis is that the effects on WOMAC Pain by the pain coping skills arm will be either partially or fully 
mediated by pain catastrophizing, whereas effects by arthritis education or usual care will either not be 
mediated by pain catastrophizing or mediated to a significantly lesser extent as compared to the pain coping 
skills arm.  Mediation will be investigated using the three-step approach described by Baron and Kenny17 and 
modified for randomized trials by Smeets and colleagues.144 A series of 3 multilevel regression analyses will be 
used to determine if pain catastrophizing mediates the effect of the interventions on pain as measured with the 
WOMAC Pain scale at the various time points. WOMAC Disability and verbal pain rating scores will serve as 
secondary outcome measures for the mediation analysis.