Protocol for the development of a tool to map systemic sclerosis pain sources, patterns, and management experiences: a Scleroderma Patient-centered Intervention Network patient-researcher partnership.

INTRODUCTION: Systemic sclerosis (SSc) is a rare, complex autoimmune rheumatic disease with multiple factors that contribute to pain. People with SSc emphasize the effect pain has on their quality of life, but no studies have systematically examined the frequency and relative importance of different SSc pain sources, patterns of pain from different sources, and pain management experiences. Our objectives are to (1) develop a tool, jointly with researchers, health care providers, and patients, to map sources of pain in SSc, determine patterns of pain from different sources, and understand pain management experiences; and (2) administer the final tool version to participants in the large multinational Scleroderma Patient-centered Intervention Network (SPIN) Cohort. METHODS: First, we will use validated pain assessment tools as templates to develop an initial version of our pain assessment tool, and we will obtain input from patient advisors to adapt it for SSc. The tool will include questions on pain sources, pain patterns, pain intensity, pain management techniques, and barriers to pain management in SSc. Second, we will conduct nominal group technique sessions with people living with SSc and health care providers who care for people with SSc to further refine the tool. Third, we will conduct individual usability testing sessions with SPIN Cohort participants. Once the tool has been finalized, we will administer it to individuals in the multinational SPIN Cohort, which currently includes over 1,300 active participants from 54 sites in 7 countries. We will perform unsupervised clustering using the KAy-Means for MIxed LArge data (KAMILA) method to identify participant subgroups with similar profiles of pain sources (present or absent) and to evaluate predictors of subgroup membership. We will use latent profile analysis to identify subgroups of participants with similar profiles based on pain intensity scores for each pain source and evaluate predictors. DISCUSSION: Once completed, our pain assessment tool will allow our team and other researchers to map sources of pain in SSc and to understand pain management experiences of people living with SSc. This knowledge will provide avenues for studies on the pathophysiology of pain in SSc and studies of interventions to improve pain management.

Minimal Detectable Changes of the HAQ-DI, PROMIS-29v2.0 Domains, and PHQ-8 in Systemic Sclerosis: A SPIN Cohort Cross-Sectional Study.

OBJECTIVE: Systemic sclerosis (SSc) is a rare, chronic, autoimmune disorder associated with disability, diminished physical function, fatigue, pain, and mental health concerns. We assessed minimal detectable changes (MDCs) of the Health Assessment Questionnaire-Disability Index (HAQ-DI), Patient Reported Outcomes Measurement Information System-29 Profile version 2.0 (PROMIS-29v2.0) domains, and Patient Health Questionnaire-8 (PHQ-8) in SSc. METHODS: Scleroderma Patient-centered Intervention Network Cohort participants completed the HAQ-DI, PROMIS-29v2.0 domains, and PHQ-8 at baseline assessments from April 2014 until August 2023. We estimated MDC95 and MDC90 with 95% confidence intervals (CI) generated via the percentile bootstrapping method resampling 1000 times. We compared MDC estimates by age, sex and SSc subtype. RESULTS: A total of 2,571 participants were included. Most were female (N = 2,241; 87%), and 38% (N = 976) had diffuse SSc. Mean (SD) age was 54.9 (12.7) years and duration since onset of first non-Raynaud phenomenon symptom 10.8 (8.7) years. MDC95 estimate was 0.41 points (95% CI: 0.40 to 0.42) for the HAQ-DI, between 4.88 points (95% CI: 4.72 to 5.05) and 9.02 points (95% CI: 8.80 to 9.23) for the 7 PROMIS-29v2.0 domains, and 5.16 points (95% CI: 5.06 to 5.26) for the PHQ-8. MDC95 estimates were not materially different across subgroups. CONCLUSION: MDC95 and MDC90 estimates were precise and similar across age, sex and SSc subtype groups. HAQ-DI MDC95 and MDC90 were substantially larger than previous estimates of HAQ-DI minimal important difference from several small studies. Minimally important differences of all measures should be evaluated in large studies using anchor-based methods.

Physical activity during COVID-19 in people with systemic sclerosis: A Scleroderma Patient-centred Intervention Network COVID-19 Cohort longitudinal study.

Introduction/Objective: People with systemic sclerosis (SSc) face barriers to physical activity. Few studies have described physical activity in SSc, and none have explored physical activity longitudinally during COVID-19. We evaluated physical activity from April 2020 to March 2022 among people with SSc. Methods: The Scleroderma Patient-centred Intervention Network (SPIN) COVID-19 Cohort was launched in April 2020 and included participants from the ongoing SPIN Cohort plus external enrolees. Participants completed measures bi-weekly through July 2020, then every 4 weeks afterwards (28 assessments). Physical activity was assessed via the self-reported International Physical Activity Questionnaire-Elderly. Analyses included estimated means with 95% confidence intervals for physical activity across assessments. Missing data were imputed for main analyses. Sensitivity analyses included evaluating only participants who completed >90% of items for >21 of 28 possible assessments ('completers') and stratified analyses by sex, age, country and SSc subtype. Results: A total of 800 people with SSc enrolled. Mean age was 55.6 (standard deviation (SD) = 12.6) years. Physical activity significantly decreased from April 2020 to March 2021 (standardized mean difference (SMD) = -0.17, 95% confidence interval (CI) = -0.26 to -0.07) and was stable from March 2021 to March 2022 (SMD = -0.05, 95% CI = -0.15 to 0.05). Results were similar for completers and subgroups. The proportion of participants who met World Health Organization minimum physical activity recommendations of at least 150 min of moderate-to-vigorous activity per week ranged from 63% to 82% across assessments. Conclusion: Physical activity decreased by a relatively small amount, on average, across the pandemic. Most participants met recommended physical activity levels.

Association of COVID-19 vaccination and anxiety symptoms: A Scleroderma Patient-centered Intervention Network (SPIN) Cohort longitudinal study.

OBJECTIVE: Symptoms of anxiety increased early in the COVID-19 pandemic among people with systemic sclerosis (SSc) then returned to pre-pandemic levels, but this was an aggregate finding and did not evaluate whether vaccination may have contributed to reduced anxiety symptom levels. We investigated whether being vaccinated for COVID-19 was associated with reduced anxiety symptoms among people with SSc. METHODS: The longitudinal Scleroderma Patient-centered Intervention Network (SPIN) COVID-19 Cohort was launched in April 2020 and included participants from the ongoing SPIN Cohort and external enrollees. Participants completed measures bi-weekly through July 2020, then every 4 weeks afterwards through August 2022 (32 assessments). We used linear mixed models to evaluate longitudinal trends of PROMIS Anxiety 4a v1.0 anxiety domain scores and their association with vaccination. RESULTS: Among 517 participants included in analyses, 489 (95%) were vaccinated by September 2021, and no participants were vaccinated subsequently. Except for briefly at the beginning, when few had received a vaccine, and end, when only 28 participants remained unvaccinated, anxiety symptom trajectories were largely overlapping. Participants who were never vaccinated had higher anxiety symptoms by August 2022, but there were no other differences, and receiving a vaccination did not appear to change anxiety symptom trajectories meaningfully. CONCLUSION: Vaccination did not appear to influence changes in anxiety symptoms among vulnerable people with SSc during the COVID-19 pandemic. This may be due to people restricting their behavior when they were unvaccinated and returning to more normal social engagement once vaccinated to maintain a steady level of anxiety symptoms.

Translation and linguistic validation of 24 PROMIS item banks into French.

PURPOSE: The Patient-Reported Outcome Measurement Information System (PROMIS®) was developed to provide reliable, valid, and normed item banks to measure health. The item banks provide standardized scores on a common metric allowing for individualized, brief assessment (computerized adaptive tests), short forms (e.g. heart failure specific), or profile assessments (e.g. PROMIS-29). The objective of this study was to translate and linguistically validate 24 PROMIS adult item banks into French and highlight cultural nuances arising during the translation process. METHODS: We used the FACIT translation methodology. Forward translation into French by two native French-speaking translators was followed by reconciliation by a third native French-speaking translator. A native English-speaking translator fluent in French then completed a back translation of the reconciled version from French into English. Three independent reviews by bilingual translators were completed to assess the clarity and consistency of terminology and equivalency across the English source and French translations. Reconciled versions were evaluated in cognitive interviews for conceptual and linguistic equivalence. RESULTS: Twenty-four adult item banks were translated: 12 mental health, 10 physical health, and two social health. Interview data revealed that 577 items of the 590 items translated required no revisions. Conceptual and linguistic differences were evident for 11 items that required iterations to improve conceptual equivalence and two items were revised to accurately reflect the English source. CONCLUSION: French translations of 24 item banks were created for routine clinical use and research. Initial translation supported conceptual equivalence and comprehensibility. Next steps will include validation of the item banks.

Having More Tender Than Swollen Joints Is Associated With Worse Patient-Reported Outcomes in Patients With Early RA.

BACKGROUND/OBJECTIVE: In patients with rheumatoid arthritis (RA), high tender-swollen joint differences (TSJDs) have been associated with worse outcomes. A better understanding of the phenotype and impact of high TSJD on patient-reported outcomes (PROs) in early RA may lead to earlier personalized treatment targeting domains that are important to patients today. Our objectives were to evaluate the impact of TSJD on updated PROs in patients with early RA over 1 year and to determine differences in associations by joint size. METHODS: This longitudinal cohort study followed patients with active, early RA enrolled in the Canadian Early Arthritis Cohort between 2016 and 2022, who completed clinical assessments and PROMIS-29 measures over 1 year. Twenty-eight joint counts were performed and TSJDs calculated. Adjusted associations between TSJD and PROMIS-29 scores were estimated using separate linear-mixed models. Separate analyses of large versus small-joint TJSDs were performed. RESULTS: Patients with early RA (n = 547; 70% female; mean [SD] age, 56 [15] years; mean [SD] symptom duration, 5.3 [2.9] months) were evaluated. A 1-point increase in TSJD was significantly associated with worse PROMIS T-scores in all domains: physical function (adjusted regression coefficient, -0.27; 95% confidence interval [CI], -0.39, -0.15), social participation (adjusted regression coefficient, -0.34; 95% CI, -0.50, -0.19), pain interference (adjusted regression coefficient, 0.49; 95% CI, 0.35, 0.64), sleep problems (adjusted regression coefficient, 0.29; 95% CI, 0.16, 0.43), fatigue (adjusted regression coefficient, 0.34; 95% CI, 0.18, 0.50), anxiety (adjusted regression coefficient, 0.23; 95% CI, 0.08, 0.38), and depression (adjusted regression coefficient, 0.20; 95% CI, 0.06, 0.35). Large-joint TSJD was associated with markedly worse PROs compared with small-joint TSJD. CONCLUSIONS: Elevated TSJD is associated with worse PROs particularly pain interference, social participation, and fatigue. Patients with more tender than swollen joints, especially large joints, may benefit from earlier, targeted therapeutic interventions.

"I couldn't carry on taking a drug like that": A qualitative study of patient perspectives on side effects from rheumatology drugs.

OBJECTIVES: There is growing interest in collecting outcome information directly from patients in clinical trials. This study evaluates what patients with rheumatic and musculoskeletal diseases (RMDs) consider important to know about symptomatic side effects they may experience from a new prescription drug. METHODS: Patients with inflammatory arthritis, who had one or more prescribed drugs for their disease for at least 12 months, participated in focus groups and individual interviews. Discussions were analysed using reflexive thematic analysis. RESULTS: We conducted seven focus groups with 34 participants across three continents. We found four overarching and two underpinning themes. The 'impact on life' was connected to participants 'daily life', 'family life', 'work life', and 'social life'. In 'psychological and physical aspects' participants described 'limitation to physical function', 'emotional dysregulation' and 'an overall mental state'. Extra tests, hospital visits and payment for medication were considered a 'time, energy and financial burden' of side effects. Participants explained important measurement issues to be 'severity', 'frequency', and 'duration'. Underpinning these issues, participants evaluated the 'benefit-harm-balance' which includes 'the cumulative burden' of having several side effects and the persistence of side effects over time. CONCLUSIONS: In treatment for RMDs, there seems to be an urgent need for feasible measures of patient-reported bother (impact on life and cumulative burden) from side effects and the benefit-harm-balance. These findings contribute new evidence in support of a target domain-an outcome that represents the patient voice evaluating the symptomatic treatment-related side effects for people with RMDs enrolled in clinical trials.

Factors associated with satisfaction with social roles and activities among people with systemic sclerosis: a Scleroderma Patient-centered Intervention Network (SPIN) cohort cross-sectional study.

OBJECTIVE: The objectives were to (1) compare satisfaction with social roles and activities in a large multinational systemic sclerosis (SSc) cohort to general population normative data and (2) identify sociodemographic, lifestyle and SSc disease factors associated with satisfaction with social roles and activities. METHODS: Participants in the Scleroderma Patient-centered Intervention Network Cohort completed the Patient Reported Outcomes Information System Version 2 satisfaction with social roles and activities domain questionnaire. Multivariable regression was used to assess associations with sociodemographic, lifestyle and disease factors. RESULTS: Among 2385 participants, mean satisfaction with social roles and activities T-score (48.1, SD=9.9) was slightly lower than the US general population (mean=50, SD=10). Factors independently associated with satisfaction were years of education (0.54 per SD, 95% CI 0.14 to 0.93); non-White race or ethnicity (-1.13, 95% CI -2.18 to -0.08); living in Canada (-1.33, 95% CI -2.40 to -0.26 (reference USA)) or the UK (-2.49, 95% CI -3.92 to -1.06); body mass index (-1.08 per SD, 95% CI -1.47 to -0.69); gastrointestinal involvement (-3.16, 95% CI -4.27 to -2.05); digital ulcers (-1.90, 95% CI -3.05 to -0.76); moderate (-1.62, 95% CI -2.78 to -0.45) or severe (-2.26, 95% CI -3.99 to -0.52) small joint contractures; interstitial lung disease (-1.11, 95% CI -1.97 to -0.25); pulmonary arterial hypertension (-2.69, 95% CI -4.08 to -1.30); rheumatoid arthritis (-2.51, 95% CI -4.28 to -0.73); and Sjogren's syndrome (-2.42, 95% CI -3.96 to -0.88). CONCLUSION: Mean satisfaction with social roles and activities is slightly lower in SSc than the general population and associated with multiple sociodemographic and disease factors.

Factors associated with physical function among people with systemic sclerosis: a SPIN cohort cross-sectional study.

OBJECTIVES: To compare physical function in systemic sclerosis (SSc, scleroderma) to general population normative data and identify associated factors. METHODS: Scleroderma Patient-centered Intervention Network Cohort participants completed the Physical Function domain of the Patient-Reported Outcomes Measurement Information System Version 2 upon enrolment. Multivariable linear regression was used to assess associations of sociodemographic, lifestyle, and disease-related variables. RESULTS: Among 2,385 participants, mean physical function T-score (43.7, SD = 8.9) was ∼2/3 of a standard deviation (SD) below the US general population (mean = 50, SD = 10). Factors associated in multivariable analysis included older age (-0.74 points per SD years, 95% CI -0.78 to -1.08), female sex (-1.35, -2.37 to -0.34), fewer years of education (-0.41 points per SD in years, -0.75 to -0.07), being single, divorced, or widowed (-0.76, -1.48 to -0.03), smoking (-3.14, -4.42 to -1.85), alcohol consumption (0.79 points per SD drinks per week, 0.45-1.14), BMI (-1.41 points per SD, -1.75 to -1.07), diffuse subtype (-1.43, -2.23 to -0.62), gastrointestinal involvement (-2.58, -3.53 to -1.62), digital ulcers (-1.96, -2.94 to -0.98), moderate (-1.94, -2.94 to -0.93) and severe (-1.76, -3.24 to -0.28) small joint contractures, moderate (-2.10, -3.44 to -0.76) and severe (-2.54, -4.64 to -0.44) large joint contractures, interstitial lung disease (-1.52, -2.27 to -0.77), pulmonary arterial hypertension (-3.72, -4.91 to -2.52), rheumatoid arthritis (-2.10, -3.64 to -0.56) and idiopathic inflammatory myositis (-2.10, -3.63 to -0.56). CONCLUSION: Physical function is impaired for many individuals with SSc and associated with multiple disease factors.

The association of resilience and positive mental health in systemic sclerosis: A Scleroderma Patient-centered Intervention Network (SPIN) cohort cross-sectional study.

OBJECTIVE: A previous study using Scleroderma Patient-centered Intervention Network (SPIN) Cohort data identified five classes of people with systemic sclerosis (also known as scleroderma) based on patient-reported somatic (fatigue, pain, sleep) and mental health (anxiety, depression) symptoms and compared indicators of disease severity between classes. Across four classes ("low", "normal", "high", "very high"), there were progressively worse somatic and mental health outcomes and greater disease severity. The fifth ("high/low") class, however, was characterized by high disease severity, fatigue, pain, and sleep but low mental health symptoms. We evaluated resilience across classes and compared resilience between classes. METHODS: Cross-sectional study. SPIN Cohort participants completed the 10-item Connor-Davidson-Resilience Scale (CD-RISC) and PROMIS v2.0 domains between August 2022 and January 2023. We used latent profile modeling to identify five classes as in the previous study and multiple linear regression to compare resilience levels across classes, controlling for sociodemographic and disease variables. RESULTS: Mean CD-RISC score (N = 1054 participants) was 27.7 (standard deviation = 7.3). Resilience decreased progressively across "low" to "normal" to "high" to "very high" classes (mean 4.7 points per step). Based on multiple regression, the "high/low" class exhibited higher resilience scores than the "high" class (6.0 points, 95% confidence interval [CI] 4.9 to 7.1 points; standardized mean difference = 0.83, 95% CI 0.67 to 0.98). CONCLUSIONS: People with worse disease severity and patient-reported outcomes reported substantially lower resilience, except a class of people with high disease severity, fatigue, pain, and sleep disturbance but positive mental health and high resilience.

Consensus on the definitions and descriptions of the domains of the OMERACT Core Outcome Set for shared decision making interventions in rheumatology trials.

OBJECTIVE: To gain consensus on the definitions and descriptions of the domains of the Outcome Measures in Rheumatology (OMERACT) core domain set for rheumatology trials evaluating shared decision making (SDM) interventions. METHODS: Following the OMERACT Handbook methods, our Working Group (WG), comprised of 90 members, including 17 patient research partners (PRPs) and 73 clinicians and researchers, had six virtual meetings in addition to email exchanges to develop draft definitions and descriptions. The WG then conducted an international survey of its members to gain consensus on the definitions and descriptions. Finally, the WG members had virtual meetings and e-mail exchanges to review survey results and finalize names, definitions and descriptions of the domains. RESULTS: WG members contributed to developing the definitions. Fifty-two members representing four continents and 13 countries completed the survey, including 15 PRPs, 33 clinicians and 37 researchers. PRPs and clinicians/researchers agreed with all definitions and descriptions with agreements ranging from 87% to 100%. Respondents suggested wording changes to the names, definitions and descriptions to better reflect the domains. Discussions led to further simplification and clarification to address common questions/concerns about the domains. CONCLUSION: Our WG reached consensus on the definitions and descriptions of the domains of the core domain set for rheumatology trials of SDM interventions. This step is crucial to understand each domain and provides the foundation to identify instruments to measure each domain for inclusion in the Core Outcome Measurement Set. CLINICAL SIGNIFICANCE: The current study provides consensus-based definitions and descriptions for the domains of the OMERACT core domain set for shared decision making interventions from patients/caregivers, clinicians and researchers. This is a crucial step to understand each domain and provides the foundation to identify instruments to measure each domain for inclusion in the Core Outcome Measurement Set for trials of SDM interventions.

Moderators of Loneliness Trajectories in People with Systemic Sclerosis During the COVID-19 Pandemic: A SPIN COVID-19 Cohort Longitudinal Study.

BACKGROUND: Many individuals with systemic sclerosis (SSc) are at heightened risk for COVID-19 related morbidity and isolation due to interstitial lung disease, frailty, and immunosuppressant use. Minimal research has explored loneliness predictors in individuals with chronic illnesses during COVID-19. This study evaluated moderators of loneliness trajectories in individuals with SSc during COVID-19. METHODS: Longitudinal data were analyzed across 30 timepoints from April 2020 to May 2022 from 775 adults in the Scleroderma Patient-centered Intervention Network (SPIN) COVID-19 Cohort. Hierarchical linear modeling evaluated cross-level moderators of loneliness trajectories, including marital status, baseline number of household members, number of virtual or telephone one-on-one or virtual group conversations, number of hours spent enjoying in-person household conversations or activities, and satisfaction with quality of in-person household conversations (all in the past week). Level-1 moderation analyses assessed effects of conversation, activity, and satisfaction means and slopes over time. RESULTS: Baseline values were not statistically significant moderators of loneliness trajectories. Higher mean (averaged over time) virtual or telephone one-on-one and in-person household conversations, in-person household activity, and in-person household conversation satisfaction were associated with lower loneliness trajectories (ps < .05). The relationship between in-person household conversation satisfaction and loneliness trajectory was statistically significantly but minimally attenuated over time (p < .001). CONCLUSIONS: For people with SSc, higher mean conversation, activity, and satisfaction variables were associated with lower levels of loneliness during the pandemic, but changes in these social variables were generally not predictive of changes in loneliness.

OMERACT Core outcome measurement set for shared decision making in rheumatic and musculoskeletal conditions: a scoping review to identify candidate instruments.

OBJECTIVES: Shared decision making (SDM) is a central tenet in rheumatic and musculoskeletal care. The lack of standardization regarding SDM instruments and outcomes in clinical trials threatens the comparative effectiveness of interventions. The Outcome Measures in Rheumatology (OMERACT) SDM Working Group is developing a Core Outcome Set for trials of SDM interventions in rheumatology and musculoskeletal health. The working group reached consensus on a Core Outcome Domain Set in 2020. The next step is to develop a Core Outcome Measurement Set through the OMERACT Filter 2.2. METHODS: We conducted a scoping review (PRISMA-ScR) to identify candidate instruments for the OMERACT Filter 2.2 We systematically reviewed five databases (Ovid MEDLINE®, Embase, Cochrane Library, CINAHL and Web of Science). An information specialist designed search strategies to identify all measurement instruments used in SDM studies in adults or children living with rheumatic or musculoskeletal diseases or their important others. Paired reviewers independently screened titles, abstracts, and full text articles. We extracted characteristics of all candidate instruments (e.g., measured construct, measurement properties). We classified candidate instruments and summarized evidence gaps with an adapted version of the Summary of Measurement Properties (SOMP) table. RESULTS: We found 14,464 citations, read 239 full text articles, and included 99 eligible studies. We identified 220 potential candidate instruments. The five most used measurement instruments were the Decisional Conflict Scale (traditional and low literacy versions) (n=38), the Hip/Knee-Decision Quality Instrument (n=20), the Decision Regret Scale (n=9), the Preparation for Decision Making Scale (n=8), and the CollaboRATE (n=8). Only 44 candidate instruments (20%) had any measurement properties reported by the included studies. Of these instruments, only 57% matched with at least one of the 7-criteria adapted SOMP table. CONCLUSION: We identified 220 candidate instruments used in the SDM literature amongst people with rheumatic and musculoskeletal diseases. Our classification of instruments showed evidence gaps and inconsistent reporting of measurement properties. The next steps for the OMERACT SDM Working Group are to match candidate instruments with Core Domains, assess feasibility and review validation studies of measurement instruments in rheumatic diseases or other conditions. Development and validation of new instruments may be required for some Core Domains.

Pain levels and associated factors in the Scleroderma Patient-centered Intervention Network (SPIN) cohort: a multicentre cross-sectional study.

BACKGROUND: Pain is an important and detrimental feature of systemic sclerosis but is often overlooked or deprioritised in research and clinical care. Raynaud's phenomenon, arthritis, and cutaneous ulcers are among the commonly reported disease manifestations of systemic sclerosis that could be associated with pain. We aimed to assess levels of pain intensity and interference and to evaluate disease factors associated with pain intensity and interference. METHODS: In this multicentre cross-sectional study, participants from the Scleroderma Patient-centered Intervention Network cohort who completed pain intensity and interference measures (Patient Reported Outcomes Information System-29 profile, version 2·0) as part of baseline assessments were included. Patients were recruited from 46 centres in Australia, Canada, France, Mexico, Spain, the UK, and the USA between April 15, 2014, and Jan 7, 2020. Eligible patients included those aged 18 years or older who met the criteria for systemic sclerosis devised by the American College of Rheumatology and the European League Against Rheumatism. Associations of pain intensity and pain interference with systemic sclerosis-related variables and overlap syndromes, controlling for sociodemographic variables, were assessed with multiple linear regression. Continuous independent variables were standardised. FINDINGS: Among 2157 participants with systemic sclerosis (268 [12%] males and 1889 [88%] females), 1870 (87%) reported mild, moderate, or severe pain (defined as ≥1 on a 0 to 10 scale), and 815 (38%) reported moderate or severe pain (defined as ≥5). Moreover, 757 (35%) participants reported moderate or severe pain interference. Greater pain intensity was independently associated with female sex (0·58 points [95% CI 0·26-0·90]), non-White race or ethnicity (0·50 points [0·21-0·79]), fewer years in formal education (0·30 points per SD [0·19-0·41]), country (reference: USA; Canada: 0·29 points [0·01-0·57] and UK: 0·58 points [0·21-0·95]), greater body-mass index (0·35 points per SD [0·24-0·45]); joint contractures (0·67 points [0·39-0·94]), digital ulcers (0·33 points [0·10-0·55]), gastrointestinal involvement (0·66 points [0·33-0·98]), skin involvement (measured using modified Rodnan skin score; 0·22 points per SD [0·10-0·35]), rheumatoid arthritis (0·96 points [0·50-1·43]), and Sjögren's syndrome (0·42 points [0·01-0·83]). Pain interference results were similar. INTERPRETATION: Pain is common among people with systemic sclerosis. Controlling for sociodemographic variables, greater pain was associated with multiple systemic sclerosis-related manifestations, including joint contractures, digital ulcers, gastrointestinal involvement, skin involvement, and the presence of overlap syndromes. Health-care providers should work with patients to address pain, including identifying and addressing systemic sclerosis manifestations associated with their pain, and supporting behavioural approaches to minimise impact on function and quality of life. FUNDING: Canadian Institutes of Health Research, Arthritis Society, The Lady Davis Institute for Medical Research of the Jewish General Hospital, Jewish General Hospital Foundation, McGill University, Scleroderma Society of Ontario, Scleroderma Canada, Sclérodermie Québec, Scleroderma Manitoba, Scleroderma Atlantic, Scleroderma Association of BC, Scleroderma SASK, Scleroderma Australia, Scleroderma New South Wales, Scleroderma Victoria, and Scleroderma Queensland.