BACKGROUND: Concerns about measurement validation are often expressed as imperatives to use a "valid measure". However, validity is not a characteristic of a measure. Instead, validation and validity refer to score interpretation within a context of use. This is important because responses to health measures can be different in different contexts, influencing equitable consequences of measurement. In this paper, we aim to (1) outline the theory of the argument-based approach to validity, and (2) discuss assumptions and evidence in relation to equitable consequences of measurement. METHODS: The argument-based approach to validity asks us to first state how scores will be interpreted and used in context. Assumptions underpinning this statement guide validation planning. Existing and new evidence need to be examined and evaluated in relation to the assumptions and concept of interest, leading to a reasoned evidence-based argument about the degree to which score interpretation in a context of use is valid, with consideration of potential threats to validity and measurement consequences. RESULTS: Key assumptions are described, including why evidence is needed, what evidence tells us, and the importance of assumptions in relation to the equitable consequences of measurement. CONCLUSION: The argument-based approach to validity shifts the focus of validation to a score's interpretation and use in a context, in relation to the concept of interest. A validity argument is built from evidence about the plausibility of the score interpretation in the context of use with consideration of the degree to which measurement consequences will lead to the intended beneficial health consequences and not perpetuate existing inequities in health.

The Patient-Generated Index (PGI) is an individualized measure that allows patients to define the domains most important to their quality of life (QoL). This study evaluates the usability and preliminary validity of the pediatric Patient-Generated Index (pPGI) in children who previously underwent esophageal atresia (EA) repair. We conducted a mixed-methods study including the pPGI, EuroQol-5D-Youth (EQ-5D-Y), and PROMIS Life Satisfaction Short Form-8a. Children aged 7–17 years completed self-reports, while parents served as proxies for younger children. Cognitive interviews explored how children understood and completed the pPGI, and clinician interviews assessed clinical usability. Among 25 participants, the pPGI generated 104 text responses covering a wide range of individualized domains, with eating, respiratory concerns, school impacts, and ``looking after one's health'' emerging most frequently. Weak correlations were observed between pPGI scores and both EQ-5D-Y (r = 0.33) and PROMIS (r = 0.19), consistent with the individualized nature of the measure. Cognitive interviews highlighted overall ease of understanding but identified challenges with the coin-distribution (weighting) step. Clinicians valued the pPGI for its specificity to EA-related concerns, though some preferred standardized measures for quantification. The pPGI demonstrated initial construct validity and strong acceptability, providing nuanced insights not captured by generic or disease-specific tools. These findings support the potential of the pPGI as a complementary, patient-centered measure for long-term EA follow-up.

Evidence of measurement invariance (MI) is essential to ensure that scores based on patient-reported outcome measures (PROMs) are comparable across groups or over time. Conventional methods for evaluating MI in PROMs are mostly group-based methods that require that relevant differences pertaining mainly to the lack of MI in the target populations are known a priori. Tree-based latent variable models can be used to evaluate MI in PROMs when the covariates associated with MI violation are unknown a priori. This study illustrates the implementation of a tree-based structural equation model (SEMTree) based on recursive partitioning for evaluating MI in PROMs and identifies patient characteristics associated with MI violation. Data were from 4,027 patients with coronary artery disease (CAD) who completed the 7-item Seattle Angina Questionnaire (SAQ-7) following a cardiac angiogram procedure. Structural equation modeling was used to examine factorial validity of the SAQ-7, and model fit was evaluated. SEMTree was used to identify subgroups on which the SAQ-7 items were not invariant using patients’ demographic and disease/comorbid characteristics as explanatory (i.e., splitting) variables. The median (IQR) age was 64.0 (15.1) years, while 3,172 (78.8

BACKGROUND:Multimodal prehabilitation has been shown to improve outcomes after colorectal cancer resection. However, it remains unclear which patient subgroups exhibit more favorable postoperative outcomes following multimodal prehabilitation and which characteristics characterize these subgroups. We sought to identify and describe clinically interpretable subgroups of prehabilitation participants, defined by combinations of baseline characteristics, within which differing rates of 30-day postoperative complications were observed following colorectal cancer resection. METHODS:Using a sample of participants randomized to the intervention arms of six trials of multimodal prehabilitation, recursive partitioning (classification tree) models were generated to identify subgroups with reduced 30-day complication rates. Candidate classifiers were selected for modifiability through prehabilitation and their established relevance to surgical outcomes. Two models were generated, one using baseline patient characteristics and another using post-prehabilitation characteristics. RESULTS:Among 135 (58.4%) men and 96 (41.6%) women, 34.2% (79/221) experienced 30-day postoperative complications. In the baseline tree model, those subgroups associated with the lowest complication rates had a six-minute walk distance (6MWD) ≥519 m with a RAND Short Form 36-Item Physical Functioning Score (SF-36 PFI) ≥56 (14.9%; 95% confidence interval [CI], 8.3%-25.3%) or had a combination of SF-36 PFI ≥56, 6MWD 314 to 518 m, and low risk of malnutrition (as defined by Patient-Generated Subjective Global Assessment Score <3) (6.2%; 95% CI, 1.1%-28.3%). In the post-multimodal prehabilitation tree, the lowest 30-day complication rate was observed among patients who achieved a 6MWD ≥487 m at multimodal prehabilitation completion (22.2%; 95% CI, 15.4%-30.9%). For those who could not reach this distance, ≥41 days of prehabilitation offset an otherwise elevated rate, reducing it from 46.4% to 31.8% (95% CI, 19.5%-45.7%). CONCLUSIONS:This study identifies and describes clinically interpretable subgroups of prehabilitation participants defined by combinations of baseline characteristics, within which differing rates of 30-day postoperative complications were observed following colorectal cancer resection. These subgroup profiles are intended as hypothesis-generating summaries of potential response patterns to multimodal prehabilitation, rather than as predictive tools or estimates of independent variable effects.

The social brain hypothesis suggests that primate brains evolved to manage social group complexities. While chronic HIV infection is associated with both structural brain changes and social exclusion, the possibility that social experience may contribute to brain changes has not been studied in this population. Here, we aimed to estimate the direction and strength of the relationship between gray matter volume and social network size in older people living with HIV in Canada. Fifty-eight HIV + participants (3 women) from the Positive Brain Health Now cohort underwent structural brain imaging and reported the size of their social network. We tested the relationship between social network size and gray matter volume in key brain regions previously identified in healthy older adults. Negative correlations were observed between social network size and gray matter volume in all regions of interest, adjusting for age, education, and total intracranial volume. The strongest correlation was in the left anterior cingulate cortex. We found evidence that social network size is related to gray matter volume in brain regions involved in social behavior among older people, mostly men, with longstanding HIV infection. However, the direction of this effect was opposite to that predicted. This echoes some previous work in healthy male samples. These findings suggest the need to consider social as well as biological variables in studying the brain impacts of living with HIV. Further work is needed to clarify which social variables have the greatest influence, and how they affect the brain.

Purpose Pediatric health outcomes are often assessed using proxy reports, which may not fully capture children's experiences. Children with surgical conditions face unique, changing healthcare journeys, making accurate representation challenging. This review compares child-reported health status and treatment experiences from Patient-Reported Outcome Measures (PROMs) and Patient-Reported Experience Measures (PREMs) with parent reports. Methods A systematic search, designed by a librarian and adhering to PRISMA guidelines, was conducted across eight databases up to July 2023, targeting studies using PROMs and PREMs in pediatric surgery to capture both child and parent perspectives. Two reviewers independently screened abstracts, with conflicts resolved by senior authors. The Mixed Methods Appraisal Tool (MMAT) was used for quality assessment. A meta-analysis was also performed on Pediatric Quality of Life Inventory (PedsQL™) outcomes. Results Of 5415 screened studies, 53 met inclusion criteria: 50 used PROMs, two used PREMs, and one used both. PedsQL™ appeared in 30 studies, with 16 other quality of life measures used less frequently. Twenty-two studies with PedsQL™ data from 6691 child-parent pairs were included in the meta-analysis. The pooled effect size between child- and parent-reported PedsQL™ scores was 0.98 (95 % CI: [-0.81, 2.77]), with high heterogeneity (I2 = 89 %). Conclusion This review revealed substantial variability but minimal systematic differences between child and parent reports, highlighting the need for future research to understand this variability and improve integration of child and parent perspectives in pediatric health assessments. Level of evidence I, Systematic Review or meta-analysis of RCTs (randomized control trials).

Outcome measures for dementia often fail to reflect the wide variation in symptoms, behaviors, and functional changes experienced by persons living with dementia and their caregivers. Standardized tools may not capture what matters most to patients and families, limiting clinical relevance and applicability. This poster describes the development of the Caregiver-Reported Outcome Measure for Dementia (CARED), a novel tool co-developed by researchers and family caregivers that integrates both standardization and personalization. CARED was developed through a community–academic partnership in which family caregivers served as co-researchers. Caregivers contributed to defining domains, refining items, and making decisions about measure structure. Surveys, co-created with community partners, collected caregiver responses from the US and Canada to identify CARED domains and items. The final measure consists of 27 total items, four of which are core items to be completed by all respondents, and 23 additional items from which caregivers select the four most relevant to their situation. The personalized structure of CARED ensures the inclusion of universally important outcomes while accommodating individual caregiving circumstances. The co-development process demonstrates the feasibility and value of embedding caregiver partners as partners in measurement design. CARED represents an innovative approach to dementia outcomes measurement. Through a partnership of researchers and family caregivers, the tool was developed with the lived experiences and perspectives of the population of interest. This framework may guide future efforts to develop outcome measures that are both personalized and standardized, ensuring greater clinical applicability and responsiveness to patient and caregiver needs.

Background: Parkinson’s disease (PD) affects both motor and non-motor functions, but their interactions are understudied. This study aims to explore the relationships between non-motor and motor effects of PD, focusing on depression, fatigue, gait parameters, concentration, and physical function. Methods: This is a secondary analysis of baseline data from a randomized feasibility study using a commercially available Heel2Toe™ sensor, providing auditory feedback for gait quality. The sample included PD patients with gait impairments who walked without aids. Non-motor measures were depression, fatigue, and concentration, while motor measures included gait quality (angular velocity and variability during heel strike, push-off, foot swing) and physical function (6MWT, Mini-BESTest, Neuro-QoL). Path analysis was used to assess direct and indirect effects. Results: Among 27 participants, fatigue impacted heel strike, which affected Neuro-QoL. Mood influenced push-off and Neuro-QoL, with a direct link to 6MWT. Foot swing affected Mini-BESTest and Neuro-QoL directly. Conclusions: Non-motor PD effects directly influenced specific gait parameters and physical function indicators, highlighting potential digital biomarkers of fatigue and mood for targeted interventions.

Introduction: Prehabilitation programs treat modifiable risk factors to improve surgical outcomes. However, translation of research into practice remains challenging. Logic models, visual representations of how a program works, have the potential to bridge research-to-practice gaps. We aimed to develop a logic model for prehabilitation programs in tertiary care centers by interviewing stakeholders about what should be the mission, inputs, outputs (activities and participants), and targeted outcomes for prehabilitation. METHODS:A multi-site qualitative study was conducted from June 2022 to December 2023. Interviews were analyzed using manifest summative content analysis to determine logic model items. Focus groups for member checking were performed with stakeholders throughout the analysis process. RESULTS:Sixty-one interviews were conducted with stakeholders: prehabilitation staff (n = 12), patients (n = 10), perioperative care physicians (n = 10), nurses (n = 9), dietitians (n = 9), physiotherapists (n = 5), and hospital administrators (n = 6). Findings underscored unanimous support for prehabilitation yet revealed challenges that hindered efficient and equitable resource utilization, which have been addressed in the logic model. To evaluate the success of prehabilitation, both clinician- (n = 44) and patient-oriented outcomes (n = 32) were valued by stakeholders; however, priority outcomes varied by stakeholder group: intervention adherence (prehabilitation staff), experience and satisfaction (patients), and facilitation of discharge (clinicians and hospital administrators). CONCLUSION:This co-developed logic model was designed to improve the efficiency, accessibility, and sustainability of acute care prehabilitation programs by offering a detailed blueprint. Researchers and clinicians can draw on the insights from this co-production process to develop, implement, and evaluate their own prehabilitation programs. .

Advancements in remote gait analysis technologies enable efficient, cost-effective, and personalized real-time assessments at home. This study aims to contribute evidence as to the comparability of gait quality metrics of three methods of remote gait assessment in individuals with Parkinson’s disease (PD): (1) observation, (2) a wearable sensor, and (3) pose estimation. A cross-sectional, multiple case series study was conducted remotely. Twenty participants submitted videos performing a modified TUG test with the Heel2ToeTM wearable. Each video was analysed by six raters using the checklist specific to PD developed for this study and the MediaPipe Pose Landmarker task estimation library. The observational ratings agreed with the Heel2ToeTM on detecting heel strike 64% of the time and 28.5% of the time on detecting push-off. The difference in the ranks of paired observations based on the Wilcoxon signed rank sum test between the pairs of methods compared was significant for all parameters, except for push-off when estimates from MediaPipe were compared to the ratings from the Observational Checklist, W = 86 (p = 0.498). A combination of digital technologies for remote gait analysis, such as wearable sensors and pose estimation, can detect subtle nuances in gait impairments that may be overlooked by the human eye.

BackgroundThe Getting Older Adults Outdoors (GO-OUT) randomized controlled trial showed that a workshop and 10-week park-based outdoor walk group (OWG) was superior to the workshop and 10 weekly reminders (WR) with increasing walking capacity, but not outdoor walking activity, health-promoting behavior, or successful aging, among older adults with difficulty walking outdoors. The objective of this planned process evaluation was to explore participants' perceptions of mechanisms of impact of and contextual factors influencing experiences with the interventions to help explain the observed intervention effects on study outcomes.MethodsA qualitative descriptive study involving semi-structured interviews conducted at 6-months post-baseline was conducted. A directed content analysis was undertaken.ParticipantsWe interviewed 27 adults (52% male, 48% female, mean age 76 years) from the OWG (n = 13) and WR group (n = 14).ResultsWe identified two themes including: "Holding Me Accountable to Walk More Frequently", and "We Walked Farther, With More Ease and Confidence, and We Felt Better". Participants in both groups described how the OWG and WR programs provided some degree of structure and accountability to others that increased their motivation to walk outdoors. Participants described how the OWG led to improved walking capacity (e.g., increased walking distance) and confidence. Interacting with people during OWG sessions led to a sense of enjoyment, and well-being.ConclusionsCommunity programs that incorporate structure, accountability, and opportunities for social interaction, can help improve motivation to increase outdoor walking activity and a sense of belonging for older adults with difficulty walking outdoors. Park-based OWG programs appear to convey additional important benefits related to improved physical function and well-being.Trial registrationClinicalTrials.gov NCT03292510 Date of registration: September 25, 2017.

RATIONALE:Clear, interpretable measures that account for linguistic differences are critical to accurately assess rehabilitation clinicians' propensity to integrate research evidence into clinical decision-making. AIMS AND OBJECTIVES:To contribute evidence for the clarity and interpretability of a new five-item bilingual multidimensional index of a rehabilitation clinician's propensity to integrate research evidence into clinical decision-making. METHODS:This study was conducted in three sequential steps: (1) We conducted a focus group with occupational therapists, physical therapists, and researchers to review the items and response options for clarity, consistency, and interval properties and agree on equivalency in English and French. (2) We conducted cognitive interviews whereby clinicians elaborated on their interpretation of the item, comprehensibility of items, and appropriateness of response options. Accepted modifications were integrated and tested with subsequent participants. (3) We conducted an online survey to validate the English and French equivalency of response options on a 0-100 scale. RESULTS:During the qualitative revision process (one focus group with seven participants followed by 27 interviews), the index was revised 12 times with substantial modifications to the use of research evidence and attitudes items. CONCLUSION:This study increases the clinical relevance and reduces measurement error of this brief index which can inform on individual or organizational factors influencing a clinician's propensity of integrating research evidence into decision-making and ultimately improve rehabilitation outcomes.

Geroscience is an emerging interdisciplinary field that explores the biological connections between aging and the development of chronic diseases, with the ultimate goal of identifying interventions to extend healthspan and delay age-related conditions. Recognizing the growing importance of this field, the Canadian Translational Geroscience Network (geroscience.ca) was officially launched during a conference held in Montreal on September 5-6, 2024. Building on the momentum of successful Geroscience meetings in Toronto and Montreal in 2023, this milestone event marked a transformative step forward for geroscience in Canada. This event brought together key stakeholders, including the Canadian Frailty Network (CFN), the Canadian Institutes of Health Research Institute of Aging (CIHR-IA), the Réseau Québécois de Recherche sur le Vieillissement (RQRV), the Simone & Edouard Schouela RUISSS McGill Centre of Excellence for Sustainable Health of Seniors (Schouela CEDurable), the Division of Geriatric Medicine at McGill University, and the Department of Biochemistry at the University of Toronto. Additionally, a broad coalition of geriatricians, healthcare professionals, and researchers convened to discuss and advance the field of geroscience in Canada. The 2-day conference focused on creating a multidisciplinary community to address the challenges of an aging population, emphasizing the importance of funding, national and international collaboration, and training the next generation of researchers and clinicians. Workshops and presentations showcased a range of innovative research, from cellular studies to clinical trials, aimed at understanding and treating age-related diseases. Key discussions highlighted the critical role of partnerships among research institutions, healthcare systems, and biotech companies in translating research findings into practical interventions. The Canadian Translational Geroscience Network's strategic objectives focus on expanding funding opportunities for geroscience, developing specialized training programs, and increasing membership to cultivate a diverse, multidisciplinary, and collaborative network. This network aims to include students, basic and clinical researchers, citizens, government entities, and organizations or professionals interested in advancing the geroscience field. With a clear roadmap for future growth, the Canadian Translational Geroscience Network aims to position Canada at the forefront of geroscience, fostering evidence-based innovation that improves the health and quality of life for aging populations.

Active living is a broad concept that includes exercise, recreational activities, household and occupational tasks, and active transportation to combat sedentary behaviour. It addresses social issues related to inactivity, especially among older adults, rather than focusing solely on physical fitness. As populations age, cognitive health has become a public health priority due to its impact on daily functioning and quality of life. Mayo et al. suggest that active living, influenced by physical and mental capacities and social determinants of health, could promote cognitive health in older adults. Identifying modifiable contributors to cognitive health can help reduce the burden of cognitive decline. The study aims to identify active living factors that are associated with self-reported cognitive ability and to identify profiles of people with differing degrees of self-reported cognitive ability. A secondary analysis of a cross-sectional study was conducted using survey responses from 1,612 older adults (65+ years) from Canada, the UK, the USA, and the Netherlands. The survey covered self-reported cognitive ability, personal factors, intrinsic capacity factors, SDOH, and active living indicators. The outcome was measured using the short form of the Communicating Cognitive Concerns Questionnaire (C3Q), which assesses the frequency of memory and attention lapses. Personal factors included age, sex, gender, and health conditions. Intrinsic capacity factors included sensory impairments, symptoms, and physical capacity. SDOH included nationality, education, spirituality, ethnicity, finance, residence, services, resources, neighborhood agreeableness, and social support. Active living indicators were measured using the Older Persons Active Living Related Quality of Life (OPALrQOL) measure. Multivariable analysis identified active living factors associated with self-reported cognitive ability. Logistic regression and classification tree analysis were used to identify significant predictors and profiles of cognitive ability. Significant predictors of cognitive ability included fatigue, anxiety/depression, resilience, health status, motivation, hearing ability, well-being, pain interference, and social support. Fatigue was the most critical factor, followed by anxiety/depression and resilience. Factors such as anxiety, fatigue, and lack of resilience negatively impact cognition. However, resilience can mitigate these effects. The study's findings can inform public health policies and interventions to promote cognitive health through active living.

Cognitive impairment is highly prevalent in people with progressive multiple sclerosis. Computerized cognitive training techniques have demonstrated some success at targeting core cognitive processes but are criticized for lack of transfer to real-world tasks. Research in physical rehabilitation has demonstrated the efficacy of high volume, moderate intensity task-specific training (TST) that is monitored, progressed and ideally practiced in real-world environments to enhance learning, transferability and support neurorecovery of motor functions. Findings demonstrate that TST influences activity and participation outcomes, leads to improved cortical reorganization, and focuses on activities that align with a person's daily life and specific goals. Our MSCanRehab group adapted the same principles to develop a novel comprehensive interdisciplinary approach to cognitive rehabilitation that combines core cognitive process training (CCPT), TST and a modified Cognitive Orientation to Daily Occupational Performance (CO-OP) approach. The cognitive TST was individualized to participant goals identified using the Canadian Occupational Performance Measure and further tailored based on their areas of cognitive weakness. A modified CO-OP process was utilized that incorporated CCPT and cognitive TST personalized to meet meaningful participant goals and improve occupational performance. Cognitive TST utilized goal-directed practice and repetition focused on cognitive skills (vs. impairments) using real-world tasks. Task complexity and challenge was gradually increased and progressively adapted with emphasis on active participation and problem solving. A case example demonstrates how the intervention was implemented. Components of the intervention are described using the TIDieR-Rehab checklist to ensure a comprehensive description, with emphasis on essential elements and dosage parameters.

Objective: The objective was to estimate unique patterns of change in fatigue in people with the Post-Covid Syndrome (PCS) over 15 months. Design/Subjects: The Quebec Action for Post-COVID (QAPC) study was a prospective study designed to provide a patient-centered understanding of symptoms, function, and quality of life in a self-identified Quebec sample. Methods: Participants were queried every 3 months about symptoms and function. Fatigue was measured with the 10-item Post-COVID Syndrome Fatigue Severity Measure with a transformed score ranging from 0 no fatigue to 100 extreme fatigue. Group Based Trajectory Analysis (GBTA) was used to identify patterns of longitudinal change. Results: 545 people had an average value of fatigue at baseline of 62.2 / 100 (SD: 21.6); 25% of the cohort had 5 visits. Six trajectories of individual change emerged: two groups with the highest fatigue showed persistence over time; a small group with high fatigue showed improvement; two groups with average fatigue showed improvement over time; and the group with low fatigue showed no emergence of this symptom, Conclusion High fatigue seems to persist over time while less severe fatigue abates. High fatigue may indicate a sub-syndrome within PCS similar to chronic fatigue syndrome. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This work was supported by a grant from the Fonds de Recherche de Quebec Sante and by an unrestricted grant from ScotiaBank. Neither entity had any role in study design, analysis, writing of the paper, or the decision to publish. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: McGill University Health Center Research Ethics Board gave ethical approval for this work. Project MP-37-2022-8066 I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors

People with HIV are living longer, but frailty may increase vulnerability to adverse drug interactions, particularly with sedative medications. To describe sedative co-medication patterns across frailty states using network-based analysis, and to identify key medications driving interaction complexity. This cross-sectional study analyzed 321 participants using sedatives from the Positive Brain Health Now Cohort (mean age: 53 years), categorized as robust (30.2

Health services planning and mechanism-focused research would benefit from a clearer picture of symptoms, impact, and personal priorities in post-COVID-19 syndrome (PCS). This study aimed to provide estimates of the symptom, function, and quality of life (QOL) impact of PCS. People living in Quebec, aged ≥ 18, were eligible for the Québec Action for/pour le Post-COVID (QAPC) study if they had symptoms lasting more than 4 weeks post-acute SARS-CoV-2 infection, with or without a positive COVID-19 test. Recruitment was through conventional and social media between September 2022 and December, 31, 2023. Standardized and individualized questionnaires, in French or English, were accessed through an online portal. We report cross-sectional results from the baseline visit. Individuals (n=535) spontaneously reported symptoms attributable to an average of 4.5 organ systems. Fatigue was most frequent. Effects on function and quality of life were moderate to severe and had already persisted for a year or more in the majority. Personal intervention priorities included fatigue and post-exercise malaise (PEM), cognitive symptoms, shortness of breath, and impaired taste and smell. Except for PEM, women and men did not differ importantly on measures of PCS impact, while older age was associated with lower impact. Symptom clusters defined a range of severity, with fatigue a pervasive symptom at all levels of severity. Participants in this study are likely to be representative of those seeking health care for post-COVID-19 symptoms in Canada and the results can inform next steps for clinical, research, and health services planning.