Browsing by Author "Sajobi, Tolulope T"
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Item Open Access A comparison of meta-analytic methods for synthesizing evidence from explanatory and pragmatic trials(2018-01-25) Sajobi, Tolulope T; Li, Guowei; Awosoga, Oluwagbohunmi; Wang, Meng; Menon, Bijoy K; Hill, Michael D; Thabane, LehanaAbstract Background The pragmatic–explanatory continuum indicator summary version 2 (PRECIS-2) tool has recently been developed to classify randomized clinical trials (RCTs) as pragmatic or explanatory based on their design characteristics. Given that treatment effects in explanatory trials may be greater than those obtained in pragmatic trials, conventional meta-analytic approaches may not accurately account for the heterogeneity among the studies and may result in biased treatment effect estimates. This study investigates if the incorporation of PRECIS-2 classification of published trials can improve the estimation of overall intervention effects in meta-analysis. Methods Using data from 31 published trials of intervention aimed at reducing obesity in children, we evaluated the utility of incorporating PRECIS-2 ratings of published trials into meta-analysis of intervention effects in clinical trials. Specifically, we compared random-effects meta-analysis, stratified meta-analysis, random-effects meta-regression, and mixture random-effects meta-regression methods for estimating overall pooled intervention effects. Results Our analyses revealed that mixture meta-regression models that incorporate PRECIS-2 classification as covariate resulted in a larger pooled effect size (ES) estimate (ES = − 1.01, 95%CI = [− 1.52, − 0.43]) than conventional random-effects meta-analysis (ES = − 0.15, 95%CI = [− 0.23, − 0.08]). Conclusions In addition to the original intent of PRECIS-2 tool of aiding researchers in their choice of trial design, PRECIS-2 tool is useful for explaining between study variations in systematic review and meta-analysis of published trials. We recommend that researchers adopt mixture meta-regression methods when synthesizing evidence from explanatory and pragmatic trials.Item Open Access A longitudinal magnetic resonance imaging study of neurodegenerative and small vessel disease, and clinical cognitive trajectories in non demented patients with transient ischemic attack: the PREVENT study(2018-07-16) Tariq, Sana; d’Esterre, Christopher D; Sajobi, Tolulope T; Smith, Eric E; Longman, Richard S; Frayne, Richard; Coutts, Shelagh B; Forkert, Nils D; Barber, Philip AAbstract Background Late-life cognitive decline, caused by progressive neuronal loss leading to brain atrophy years before symptoms are detected, is expected to double in Canada over the next two decades. Cognitive impairment in late life is attributed to vascular and lifestyle related risk factors in mid-life in a substantial proportion of cases (50%), thereby providing an opportunity for effective prevention of cognitive decline if incipient disease is detected earlier. Patients presenting with transient ischemic attack (TIA) commonly display some degree of cognitive impairment and are at a 4-fold increased risk of dementia. In the Predementia Neuroimaging of Transient Ischemic Attack (PREVENT) study, we will address what disease processes (i.e., Alzheimer’s vs. vascular disease) lead to neurodegeneration, brain atrophy, and cognitive decline, and whether imaging measurements of brain iron accumulation using quantitative susceptibility mapping predicts subsequent brain atrophy and cognitive decline. Methods A total of 440 subjects will be recruited for this study with 220 healthy subjects and 220 TIA patients. Early Alzheimer’s pathology will be determined by cerebrospinal fluid samples (including tau, a marker of neuronal injury, and amyloid β1–42) and by MR measurements of iron accumulation, a marker for Alzheimer’s-related neurodegeneration. Small vessel disease will be identified by changes in white matter lesion volume. Predictors of advanced rates of cerebral and hippocampal atrophy at 1 and 3 years will include in vivo Alzheimer’s disease pathology markers, and MRI measurements of brain iron accumulation and small vessel disease. Clinical and cognitive function will be assessed annually post-baseline for a period of 5-years using a clinical questionnaire and a battery of neuropsychological tests, respectively. Discussion The PREVENT study expects to demonstrate that TIA patients have increased early progressive rates of cerebral brain atrophy after TIA, before cognitive decline can be clinically detected. By developing and optimizing high-level machine learning models based on clinical data, image-based (quantitative susceptibility mapping, regional brain, and white matter lesion volumes) features, and cerebrospinal fluid biomarkers, PREVENT will provide a timely opportunity to identify individuals at greatest risk of late-life cognitive decline early in the course of disease, supporting future therapeutic strategies for the promotion of healthy aging.Item Open Access Differential item functioning of the SF-12 in a population-based regional joint replacement registry(2019-07-02) Yadegari, Iraj; Bohm, Eric; Ayilara, Olawale F; Zhang, Lixia; Sawatzky, Richard; Sajobi, Tolulope T; Lix, Lisa MAbstract Background Joint replacement, an increasingly common procedure amongst older adults, can substantially improve health-related quality of life (HRQoL). However, differential item functioning (DIF) may affect the accurate interpretation of differences in HRQoL amongst patients with different demographic and health status characteristics but the same underlying (i.e., latent) level of the investigated construct. This study tested for DIF in pre-operative SF-12 physical health (PH) and mental health (MH) sub-scale items amongst patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). Methods Data were from a population-based joint replacement registry from the Canadian province of Manitoba. TKA and THA patients who had surgery between 2009 and 2015 and completed a pre-operative assessment were included. DIF was tested using the multiple indicators multiple causes (MIMIC) method with sex, age group, body weight status, and presence of multiple comorbid conditions (i.e., multimorbidity) as covariates. Analyses were stratified by joint type. Results The study cohort included 8820 patients; 42.1% underwent THA, 57.3% were female, 32.7% were 70+ years, and 52.8% were obese. For each sub-scale, four of the six items exhibited DIF in both THA and TKA groups. Differences in the covariate effect estimates for DIF and No-DIF models on the MH latent variable were largest for age and body weight status for the THA group, and for sex and multimorbidity for the TKA group. All of the differences were small for PH. Multimorbidity had the strongest association with PH and age and sex had the strongest association with MH in the DIF models. Conclusions Demographic and health status characteristics influenced SF-12 PH and MH item responses in joint replacement populations, although the size of the effects were not large for PH. We recommend testing and adjusting for DIF effects to ensure comparability of HRQoL measures in joint replacement populations.Item Open Access Factors associated with the health status of childcare workers in southern Alberta, Canada(2019-01-03) Awosoga, Oluwagbohunmi; Hazzan, Afeez A; McIntosh, Suzanne; Dabravolskaj, Julia; Sajobi, Tolulope T; Doan, JonAbstract Objective There is growing evidence that the well-being of childcare workers has important implications for the care provided to children attending childcare centers. To add to the growing body of research in this area and to lay the groundwork for further research, we report the results of a pilot study examining factors that are associated with the health status of childcare workers in southern Alberta, Canada. The factors examined include: health control, employer’s interest in the childcare worker’s wellbeing, and actions that childcare workers are taking to improve their own health. Results A total of 260 “Workplace Health and Risks Survey 2008” questionnaires were sent to 13 licensed daycare centers in southern Alberta, Canada. Of these, a total of 110 questionnaires were completed by childcare workers at these centers and returned. Regression analysis results show that control over one’s health (Standardized Beta = .504, p < .001), employers’ knowledge of negative effects of stress (Standardized Beta = − .328, p = .017), employers’ interest in employees’ well-being (Standardized Beta = .366, p = .008), and actions that are planned to be taken to improve or maintain health in the future (Standardized Beta = .231, p = .005) are all significant predictors of health status among childcare workers.Item Open Access Global assessment of migraine severity measure: preliminary evidence of construct validity(2019-04-04) Sajobi, Tolulope T; Amoozegar, Farnaz; Wang, Meng; Wiebe, Natalie; Fiest, Kirsten M; Patten, Scott B; Jette, NathalieAbstract Background In persons with migraine, severity of migraine is an important determinant of several health outcomes (e.g., patient quality of life and health care resource utilization). This study investigated how migraine patients rate the severity of their disease and how these ratings correlate with their socio-demographic, clinical, and psycho-social characteristics. Methods This is a cohort of 263 adult migraine patients consecutively enrolled in the Neurological Disease and Depression Study (NEEDs). We obtained a broad range of clinical and patient-reported measures (e.g., patients’ ratings of migraine severity using the Global Assessment of Migraine Severity (GAMS), and migraine-related disability, as measured by the Migraine Disability Scale (MIDAS)). Depression was measured using the 9-item Patient Health Questionnaire (PHQ-9) and the 14-item Hospital Anxiety and Depression Scale (HADS). Median regression analysis was used to examine the predictors of patient ratings of migraine severity. Results The mean age for the patients was 42.5 years (SD = 13.2). While 209 (79.4%) patients were females, 177 (67.4%) participants reported “moderately severe” to “extremely severe” migraine on the GAMS, and 100 (31.6%) patients had chronic migraine. Patients’ report of severity on the GAMS was strongly correlated with patients’ ratings of MIDAS global severity question, overall MIDAS score, migraine type, PHQ-9 score, and frequency of migraine attacks. Mediation analyses revealed that MIDAS mediated the effect of depression on patient ratings of migraine severity, accounting for about 32% of the total effect of depression. Overall, migraine subtype, frequency of migraine, employment status, depression, and migraine-related disability were statistically significant predictors of patient-ratings of migraine severity. Conclusions This study highlights the impact of clinical and psychosocial determinants of patient-ratings of migraine severity. GAMS is a brief and valid tool that can be used to assess migraine severity in busy clinical settings.Item Open Access Impact of missing data on bias and precision when estimating change in patient-reported outcomes from a clinical registry(2019-06-20) Ayilara, Olawale F; Zhang, Lisa; Sajobi, Tolulope T; Sawatzky, Richard; Bohm, Eric; Lix, Lisa MAbstract Background Clinical registries, which capture information about the health and healthcare use of patients with a health condition or treatment, often contain patient-reported outcomes (PROs) that provide insights about the patient’s perspectives on their health. Missing data can affect the value of PRO data for healthcare decision-making. We compared the precision and bias of several missing data methods when estimating longitudinal change in PRO scores. Methods This research conducted analyses of clinical registry data and simulated data. Registry data were from a population-based regional joint replacement registry for Manitoba, Canada; the study cohort consisted of 5631 patients having total knee arthroplasty between 2009 and 2015. PROs were measured using the 12-item Short Form Survey, version 2 (SF-12v2) at pre- and post-operative occasions. The simulation cohort was a subset of 3000 patients from the study cohort with complete PRO information at both pre- and post-operative occasions. Linear mixed-effects models based on complete case analysis (CCA), maximum likelihood (ML) and multiple imputation (MI) without and with an auxiliary variable (MI-Aux) were used to estimate longitudinal change in PRO scores. In the simulated data, bias, root mean squared error (RMSE), and 95% confidence interval (CI) coverage and width were estimated under varying amounts and types of missing data. Results Three thousand two hundred thirty (57.4%) patients in the study cohort had complete data on the SF-12v2 at both occasions. In this cohort, mixed-effects models based on CCA resulted in substantially wider 95% CIs than models based on ML and MI methods. The latter two methods produced similar estimates and 95% CI widths. In the simulation cohort, when 50% of the data were missing, the MI-Aux method, in which a single hypothetical auxiliary variable was strongly correlated (i.e., 0.8) with the outcome, reduced the 95% CI width by up to 14% and bias and RMSE by up to 50 and 45%, respectively, when compared with the MI method. Conclusions Missing data can substantially affect the precision of estimated change in PRO scores from clinical registry data. Inclusion of auxiliary information in MI models can increase precision and reduce bias, but identifying the optimal auxiliary variable(s) may be challenging.Item Open Access Latent variable mixture models to test for differential item functioning: a population-based analysis(2017-05-15) Wu, Xiuyun; Sawatzky, Richard; Hopman, Wilma; Mayo, Nancy; Sajobi, Tolulope T; Liu, Juxin; Prior, Jerilynn; Papaioannou, Alexandra; Josse, Robert G; Towheed, Tanveer; Davison, K. S; Lix, Lisa MAbstract Background Comparisons of population health status using self-report measures such as the SF-36 rest on the assumption that the measured items have a common interpretation across sub-groups. However, self-report measures may be sensitive to differential item functioning (DIF), which occurs when sub-groups with the same underlying health status have a different probability of item response. This study tested for DIF on the SF-36 physical functioning (PF) and mental health (MH) sub-scales in population-based data using latent variable mixture models (LVMMs). Methods Data were from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective national cohort study. LVMMs were applied to the ten PF and five MH SF-36 items. A standard two-parameter graded response model with one latent class was compared to multi-class LVMMs. Multivariable logistic regression models with pseudo-class random draws characterized the latent classes on demographic and health variables. Results The CaMos cohort consisted of 9423 respondents. A three-class LVMM fit the PF sub-scale, with class proportions of 0.59, 0.24, and 0.17. For the MH sub-scale, a two-class model fit the data, with class proportions of 0.69 and 0.31. For PF items, the probabilities of reporting greater limitations were consistently higher in classes 2 and 3 than class 1. For MH items, respondents in class 2 reported more health problems than in class 1. Differences in item thresholds and factor loadings between one-class and multi-class models were observed for both sub-scales. Demographic and health variables were associated with class membership. Conclusions This study revealed DIF in population-based SF-36 data; the results suggest that PF and MH sub-scale scores may not be comparable across sub-groups defined by demographic and health status variables, although effects were frequently small to moderate in size. Evaluation of DIF should be a routine step when analysing population-based self-report data to ensure valid comparisons amongst sub-groups.Item Open Access Minimal sufficient balance randomization for sequential randomized controlled trial designs: results from the ESCAPE trial(2017-11-02) Sajobi, Tolulope T; Singh, Gurbakhshash; Lowerison, Mark W; Engbers, Jordan; Menon, Bijoy K; Demchuk, Andrew M; Goyal, Mayank; Hill, Michael DAbstract Background We describe the implementation of minimal sufficient balance randomization, a covariate-adaptive randomization technique, used for the “Endovascular treatment for Small Core and Anterior circulation Proximal occlusion with Emphasis on minimizing CT to recanalization times” (ESCAPE) trial. Methods The ESCAPE trial is a prospective, multicenter, randomized clinical trial that enrolled subjects with the following main inclusion criteria: less than 12 h from symptom onset, age 18 years or older, baseline NIHSS score > 5, ASPECTS score > 5 and computed tomography angiography (CTA) evidence of carotid T/L or M1-segment middle cerebral artery (MCA) occlusion, and at least moderate collaterals by CTA. Patients were randomized using a real-time, dynamic, Internet-based, minimal sufficient balance randomization method that balanced the study arms with respect to baseline covariates including age, sex, baseline NIHSS score, site of arterial occlusion, baseline ASPECTS score and treatment with intravenously administered alteplase. Results Permutation-based tests of group differences confirmed group balance across several baseline covariates including sex (p = 1.00), baseline NIHSS score (p = 0.95), site of arterial occlusion (p = 1.00), baseline ASPECTS score (p = 0.28), treatment with intravenously administered alteplase (p = 0.31), and age (p = 0.67). Conclusion Results from the ESCAPE trial demonstrate the feasibility and the benefit of this covariate adaptive randomization scheme in small-sample trials and for data monitoring endeavors. Trial registration ESCAPE trial – NCT01778335 – at www.clinicaltrials.gov . Registered on 29 January 2013.Item Open Access PrEvention of posttraumatic contractuRes with Ketotifen 2 (PERK 2) – protocol for a multicenter randomized clinical trial(2020-02-24) Ademola, Ayoola; Hildebrand, Kevin A; Schneider, Prism S; Mohtadi, Nicholas G H; White, Neil J; Bosse, Michael J; Garven, Alexandra; Walker, Richard E A; Sajobi, Tolulope TAbstract Background Injuries and resulting stiffness around joints, especially the elbow, have huge psychological effects by reducing quality of life through interference with normal daily activities such as feeding, dressing, grooming, and reaching for objects. Over the last several years and through numerous research results, the myofibroblast-mast cell-neuropeptide axis of fibrosis had been implicated in post-traumatic joint contractures. Pre-clinical models and a pilot randomized clinical trial (RCT) demonstrated the feasibility and safety of using Ketotifen Fumarate (KF), a mast cell stabilizer to prevent elbow joint contractures. This study aims to evaluate the efficacy of KF in reducing joint contracture severity in adult participants with operately treated elbow fractures and/or dislocations. Methods/design A Phase III randomized, controlled, double-blinded multicentre trial with 3 parallel groups (KF 2 mg or 5 mg or lactose placebo twice daily orally for 6 weeks). The study population consist of adults who are at least 18 years old and within 7 days of injury. The types of injuries are distal humerus (AO/OTA type 13) and/or proximal ulna and/or proximal radius fractures (AO/OTA type 2 U1 and/or 2R1) and/or elbow dislocations (open fractures with or without nerve injury may be included). A stratified randomization scheme by hospital site will be used to assign eligible participants to the groups in a 1:1:1 ratio. The primary outcome is change in elbow flexion-extension range of motion (ROM) arc from baseline to 12 weeks post-randomization. The secondary outcomes are changes in ROM from baseline to 6, 24 & 52 weeks, PROMs at 2, 6, 12, 24 & 52 weeks and impact of KF on safety including serious adverse events and fracture healing. Descriptive analysis for all outcomes will be reported and ANCOVA be used to evaluate the efficacy KF over lactose placebo with respect to the improvement in ROM. Discussion The results of this study will provide evidence for the use of KF in reducing post-traumatic joint contractures and improving quality of life after joint injuries. Trial registration This study was prospectively registered (July 10, 2018) with ClinicalTrials.gov reference: NCT03582176.Item Open Access Quantifying the contribution of modifiable risk factors to socio-economic inequities in cancer morbidity and mortality: a nationally representative population-based cohort study(International Epidemiological Association [Associate Organisation], Oxford University Press [University Publisher], 2021-04-12) Nejatinamini, Sara; Godley, Jenny; Minaker, Leia M; Sajobi, Tolulope T; McCormack, Gavin R; Cooke, Martin J; Nykiforuk, Candace I J; Koning, Lawrence de; Olstad, Dana LeeCompared with those with a higher socio-economic position (SEP), individuals with a lower SEP have higher cancer morbidity and mortality. However, the contribution of modifiable risk factors to these inequities is not known. This study aimed to quantify the mediating effects of modifiable risk factors to associations between SEP and cancer morbidity and mortality. Methods: This study used a prospective observational cohort design. We combined eight cycles of the Canadian Community Health Survey (2000/2001-2011) as baseline data to identify a cohort of adults (≥35 years) without cancer at the time of survey administration (n = 309 800). The cohort was linked to the Discharge Abstract Database and the Canadian Mortality Database for cancer morbidity and mortality ascertainment. Individuals were followed from the date they completed the Canadian Community Health Survey until 31 March 2013. Dates of individual first hospitalizations for cancer and deaths due to cancer were captured during this time period. SEP was operationalized using a latent variable combining measures of education and household income. Self-reported modifiable risk factors, including smoking, excess alcohol consumption, low fruit-and-vegetable intake, physical inactivity and obesity, were considered as potential mediators. Generalized structural equation modelling was used to estimate the mediating effects of modifiable risk factors in associations between low SEP and cancer morbidity and mortality in the total population and stratified by sex. Results: Modifiable risk factors together explained 45.6% of associations between low SEP and overall cancer morbidity and mortality. Smoking was the most important mediator in the total population and for males, accounting for 15.5% and 40.2% of the total effect, respectively. For females, obesity was the most important mediator. Conclusions: Modifiable risk factors are important mediators of socio-economic inequities in cancer morbidity and mortality. Nevertheless, more than half of the variance in these associations remained unexplained. Midstream interventions that target modifiable risk factors may help to alleviate inequities in cancer risk in the short term. However, ultimately, upstream interventions that target structural determinants of health are needed to reduce overall socio-economic inequities in cancer morbidity and mortality.Item Open Access The contribution of modifiable risk factors to socioeconomic inequities in cardiovascular disease morbidity and mortality: a nationally representative population-based cohort study(Elsevier, 2023-04-12) Nejatinamini, Sara; Campbell, David JT; Godley, Jenny; Minaker, Leia M; Sajobi, Tolulope T; McCormack, Gavin R; Olstad, Dana LeeThis study examined the individual and joint effects of modifiable risk factors mediating the associations between socioeconomic position (SEP) and morbidity and mortality from cardiovascular diseases (CVD) in a nationally representative sample of adults in Canada. Participants in the Canadian Community Health Survey (n=289,800) were followed longitudinally for CVD morbidity and mortality using administrative health and mortality data. SEP was measured as a latent variable consisting of household income and individual educational attainment. Mediators included smoking, physical inactivity, obesity, diabetes and hypertension. The primary outcome was CVD morbidity and mortality, defined as the first fatal/nonfatal CVD event during follow-up (median 6.2 years). Generalized structural equation modeling tested the mediating effects of modifiable risk factors in associations between SEP and CVD in the total population and stratified by sex. Lower SEP was associated with 2.5 times increased odds of CVD morbidity and mortality (OR: 2.52, 95% CI: 2.28, 2.76). Modifiable risk factors mediated 74% of associations between SEP and CVD morbidity and mortality in the total population and were more important mediators of associations in females (83%) than males (62%). Smoking mediated these associations independently and jointly with other mediators. The mediating effects of physical inactivity were through joint mediating effects with obesity, diabetes or hypertension. There were additional joint mediating effects of obesity through diabetes or hypertension in females. Findings point to modifiable risk factors as important targets for interventions along with interventions that target structural determinants of health to reduce socioeconomic inequities in CVD.