International Classification of Diseases Codes are Useful in Identifying Cirrhosis in Administrative Databases.

BACKGROUND: Health administrative databases are essential to define patient populations, make socioeconomic predictions, and facilitate medical research and healthcare planning. The accuracy of this data is dependent on valid codes/coding algorithms. AIMS: The aim of this study was to systematically identify and summarize the validity of International Classification of Diseases (ICD) codes for identifying patients with cirrhosis in administrative data. METHODS: Electronic databases, MEDLINE (via Ovid), EMBASE (via Ovid), the Web of Science, and CINAHL (via EBSCOhost), were searched for validation studies which compared ICD codes related to cirrhosis to a clinical reference standard, and reported statistical measures of performance. RESULTS: Fourteen studies were included in the review. There was a large variation in the algorithms used to validate ICD codes to diagnose cirrhosis. Despite the variation, the positive predictive value (PPV) was greater than 84% and the specificity was greater than 75% in the majority of the studies. The negative predictive value (NPV) was lower, but still was associated with values greater than 70% in the majority of studies. Sensitivity data varied significantly with values ranging from 0.27 to 99%. CONCLUSIONS: Evaluated ICD codes for cirrhosis, including codes for chronic liver disease, cirrhosis-specific codes, and cirrhosis-related complications, have demonstrated variable sensitivity and reasonable specificity for the identification of cirrhosis. Additional research is needed to maximize the identification of persons with cirrhosis to avoid underestimating the burden of disease.

Obesity and overweight in Bangladeshi children and adolescents: a scoping review.

BACKGROUND: Obesity and overweight in children and adolescents is an emerging public health concern alongside under-nutrition in low and middle income countries. Our aim was to conduct a scoping review of literature to ascertain what is known about childhood and adolescent overweight and/or obesity in Bangladesh. METHOD: Using the scoping review based on York methodology, a comprehensive search of published academic articles, conference proceedings and grey literature was carried out through PubMed, BanglaJOL, Google and Google scholar limited to English-written papers. We summarized prevalence, risk factors and health outcomes of obesity/overweight in young children and adolescents aged between 0 to 19 years old in Bangladesh and highlighted use of different reference standards to measure childhood obesity. RESULTS: In total 21 studies met the inclusion criteria. Nearly all of the reviewed articles used data from cross sectional studies, while only two used case-control design. Overall thirteen studies (62%) were primary research and eight (38%) included secondary data. Studies indicated an increasing trend in childhood obesity over time. Prevalence ranged from less than 1% to 17.9% based on different reference standards, with higher percentage amongst urban children across different age groups and sexes. CONCLUSION: This review demonstrated paucity of comprehensive literature on childhood obesity in Bangladesh, which might be explored through population-based prospective studies based on strong methodology and uniform reference standards. Sustainable and scalable preventative measures targeting high risk groups are required to avoid further rise.

Seeking Care for Children with Intellectual and/or Developmental Disabilities in the Emergency Department: A Mixed Methods Systematic Review of Parents' Experiences and Information Needs.

The objective of this review was to explore parents' experiences and information needs regarding management of their child with an intellectual and/or developmental disability (IDD) in the emergency department (ED). We searched six electronic databases and grey literature to identify primary studies in English published since 2000. We synthesized quantitative and qualitative outcome data simultaneously using a convergent integrated approach and used a Mixed Methods Appraisal Tool (MMAT) to assess methodological quality of the included studies. Nine articles derived from seven studies were included (3 qualitative, 3 quantitative, 1 mixed method). Four main themes related to parents' self-reported experiences were identified: 1) appropriateness of the ED to manage and support their child; 2) acknowledgement/recognition of their child's IDD and incorporation of those considerations into overall care and management; 3) managing and navigating the ED environment; and 4) decision to disclose their child's condition when visiting the ED. Two articles provided data relevant to information needs, highlighting parents' desire to have resources supporting ED orientation and access to services within and outside of the ED setting. From the limited number of studies, it was evident that parents wanted better communication with healthcare providers and a greater understanding by ED staff around physical space settings needed to support their child. Resources supporting ED staff and parents to communicate effectively and work together can ensure that children with IDDs care needs are met. Further research into understanding parents' experiences and information needs related to managing a child with an IDD in the ED is needed to guide the development of effective resources.

Patient preferences for breast cancer screening: a systematic review update to inform recommendations by the Canadian Task Force on Preventive Health Care.

BACKGROUND: Different guideline panels, and individuals, may make different decisions based in part on their preferences. Preferences for or against an intervention are viewed as a consequence of the relative importance people place on the expected or experienced health outcomes it incurs. These findings can then be considered as patient input when balancing effect estimates on benefits and harms reported by empirical evidence on the clinical effectiveness of screening programs. This systematic review update examined the relative importance placed by patients on the potential benefits and harms of mammography-based breast cancer screening to inform an update to the 2018 Canadian Task Force on Preventive Health Care's guideline on screening. METHODS: We screened all articles from our previous review (search December 2017) and updated our searches to June 19, 2023 in MEDLINE, PsycINFO, and CINAHL. We also screened grey literature, submissions by stakeholders, and reference lists. The target population was cisgender women and other adults assigned female at birth (including transgender men and nonbinary persons) aged ≥ 35 years and at average or moderately increased risk for breast cancer. Studies of patients with breast cancer were eligible for health-state utility data for relevant outcomes. We sought three types of data, directly through (i) disutilities of screening and curative treatment health states (measuring the impact of the outcome on one's health-related quality of life; utilities measured on a scale of 0 [death] to 1 [perfect health]), and (ii) other preference-based data, such as outcome trade-offs, and indirectly through (iii) the relative importance of benefits versus harms inferred from attitudes, intentions, and behaviors towards screening among patients provided with estimates of the magnitudes of benefit(s) and harms(s). For screening, we used machine learning as one of the reviewers after at least 50% of studies had been reviewed in duplicate by humans; full-text selection used independent review by two humans. Data extraction and risk of bias assessments used a single reviewer with verification. Our main analysis for utilities used data from utility-based health-related quality of life tools (e.g., EQ-5D) in patients; a disutility value of about 0.04 can be considered a minimally important value for the Canadian public. When suitable, we pooled utilities and explored heterogeneity. Disutilities were calculated for screening health states and between different treatment states. Non-utility data were grouped into categories, based on outcomes compared (e.g. for trade-off data), participant age, and our judgements of the net benefit of screening portrayed by the studies. Thereafter, we compared and contrasted findings while considering sample sizes, risk of bias, subgroup findings and data on knowledge scores, and created summary statements for each data set. Certainty assessments followed GRADE guidance for patient preferences and used consensus among at least two reviewers. FINDINGS: Eighty-two studies (38 on utilities) were included. The estimated disutilities were 0.07 for a positive screening result (moderate certainty), 0.03-0.04 for a false positive (FP; "additional testing" resolved as negative for cancer) (low certainty), and 0.08 for untreated screen-detected cancer (moderate certainty) or (low certainty) an interval cancer. At ≤12 months, disutilities of mastectomy (vs. breast-conserving therapy), chemotherapy (vs. none) (low certainty), and radiation therapy (vs. none) (moderate certainty) were 0.02-0.03, 0.02-0.04, and little-to-none, respectively, though in each case findings were somewhat limited in their applicability. Over the longer term, there was moderate certainty for little-to-no disutility from mastectomy versus breast-conserving surgery/lumpectomy with radiation and from radiation. There was moderate certainty that a majority (>50%) and possibly a large majority (>75%) of women probably accept up to six cases of overdiagnosis to prevent one breast-cancer death; there was some uncertainty because of an indication that overdiagnosis was not fully understood by participants in some cases. Low certainty evidence suggested that a large majority may accept that screening may reduce breast-cancer but not all-cause mortality, at least when presented with relatively high rates of breast-cancer mortality reductions (n = 2; 2 and 5 fewer per 1000 screened), and at least a majority accept that to prevent one breast-cancer death at least a few hundred patients will receive a FP result and 10-15 will have a FP resolved through biopsy. An upper limit for an acceptable number of FPs was not evaluated. When using data from studies assessing attitudes, intentions, and screening behaviors, across all age groups but most evident for women in their 40s, preferences reduced as the net benefit presented by study authors decreased in magnitude. In a relatively low net-benefit scenario, a majority of patients in their 40s may not weigh the benefits as greater than the harms from screening whereas for women in their 50s a large majority may prefer screening (low certainty evidence for both ages). There was moderate certainty that a large majority of women 50 years of age and 50 to 69 years of age, who have usually experienced screening, weigh the benefits as greater than the harms from screening in a high net-benefit scenario. A large majority of patients aged 70-71 years who have recently screened probably think the benefits outweigh the harms of continuing to screen. A majority of women in their mid-70s to early 80s may prefer to continue screening. CONCLUSIONS: Evidence across a range of data sources on how informed patients value the potential outcomes from breast-cancer screening will be useful during decision-making for recommendations. The evidence suggests that all of the outcomes examined have importance to women of any age, that there is at least some and possibly substantial (among those in their 40s) variability across and within age groups about the acceptable magnitude of effects across outcomes, and that provision of easily understandable information on the likelihood of the outcomes may be necessary to enable informed decision making. Although studies came from a wide range of countries, there were limited data from Canada and about whether findings applied well across an ethnographically and socioeconomically diverse population. SYSTEMATIC REVIEW REGISTRATION: Protocol available at Open Science Framework https://osf.io/xngsu/ .

Screening for lung cancer with computed tomography: protocol for systematic reviews for the Canadian Task Force on Preventive Health Care.

PURPOSE: Lung cancer is the leading cause of cancer deaths in Canada, and because early cancers are often asymptomatic screening aims to prevent mortality by detecting cancer earlier when treatment is more likely to be curative. These reviews will inform updated recommendations by the Canadian Task Force on Preventive Health Care on screening for lung cancer. METHODS: We will update the review on the benefits and harms of screening with CT conducted for the task force in 2015 and perform de novo reviews on the comparative effects between (i) trial-based selection criteria and use of risk prediction models and (ii) trial-based nodule classification and different nodule classification systems and on patients' values and preferences. We will search Medline, Embase, and Cochrane Central (for questions on benefits and harms from 2015; comparative effects from 2012) and Medline, Scopus, and EconLit (for values and preferences from 2012) via peer-reviewed search strategies, clinical trial registries, and the reference lists of included studies and reviews. Two reviewers will screen all citations (including those in the previous review) and base inclusion decisions on consensus or arbitration by another reviewer. For benefits (i.e., all-cause and cancer-specific mortality and health-related quality of life) and harms (i.e., overdiagnosis, false positives, incidental findings, psychosocial harms from screening, and major complications and mortality from invasive procedures as a result of screening), we will include studies of adults in whom lung cancer is not suspected. We will include randomized controlled trials comparing CT screening with no screening or alternative screening modalities (e.g., chest radiography) or strategies (e.g., CT using different screening intervals, classification systems, and/or patient selection via risk models or biomarkers); non-randomized studies, including modeling studies, will be included for the comparative effects between trial-based and other selection criteria or nodule classification methods. For harms (except overdiagnosis) we will also include non-randomized and uncontrolled studies. For values and preferences, the study design may be any quantitative design that either directly or indirectly measures outcome preferences on outcomes pertaining to lung cancer screening. We will only include studies conducted in Very High Human Development Countries and having full texts in English or French. Data will be extracted by one reviewer with verification by another, with the exception of result data on mortality and cancer incidence (for calculating overdiagnosis) where duplicate extraction will occur. If two or more studies report on the same comparison and it is deemed suitable, we will pool continuous data using a mean difference or standardized mean difference, as applicable, and binary data using relative risks and a DerSimonian and Laird model unless events are rare (< 1%) where we will pool odds ratios using Peto's method or (if zero events) the reciprocal of the opposite treatment arm size correction. For pooling proportions, we will apply suitable transformation (logit or arcsine) depending on the proportions of events. If meta-analysis is not undertaken we will synthesize the data descriptively, considering clinical and methodological differences. For each outcome, two reviewers will independently assess within- and across-study risk of bias and rate the certainty of the evidence using GRADE (Grading of Recommendations Assessment, Development, and Evaluation), and reach consensus. DISCUSSION: Since 2015, additional trials and longer follow-ups or additional data (e.g., harms, specific patient populations) from previously published trials have been published that will improve our understanding of the benefits and harms of screening. The systematic review of values and preferences will allow fulsome insights that will inform the balance of benefits and harms. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022378858.

Reported costs of children with medical complexity-A systematic review.

Examining reported costs for Children with Medical Complexity (CMCs) is essential because costing and resource utilization studies influence policy and operational decisions. Our objectives were to (1) examine how authors identified CMCs in administrative databases, (2) compare reported costs for the CMC population in different study settings, and (3) analyze author recommendations related to reported costs. We undertook a systematic search of the following databases: Medical Literature Analysis and Retrieval System Online, Excerpta Medica dataBase, Cumulative Index to Nursing and Allied Health Literature, and Cochrane Library with a focus on CMCs as a heterogeneous group. The most common method used n = 11 (41%) to identify the CMC population in administrative data was the Complex Chronic Conditions methodology. The majority of included studies reported on health care service costs n = 24 (89%). Only n = 3 (11%) of the studies included costs from the family perspective. Author recommendations included standardizing how costs are reported and including the family perspective when making care delivery or policy decisions. Health system administrators and policymakers must consider the limitations of reported costs when assessing local costing studies or comparing costs across jurisdictions.

Children at risk of anaphylaxis: A mixed-studies systematic review of parents' experiences and information needs.

Objective: To explore parents' self-reported experiences and information needs regarding recognition and management of pediatric anaphylaxis. Methods: We searched Ovid Medline, Ovid PsychInfo, CINAHL Plus, the Cochrane Library, and grey literature to identify primary studies in English or French published since 2000. We used a mixed-method appraisal tool and convergent integrated approach to assess quality and synthesize data, respectively. Results: 43 studies were included (22 quantitative, 19 qualitative, and 2 mixed-method); 77% of studies had high methodological quality. Parents' experiences were categorized as: recognizing an anaphylactic reaction; managing and responding to a reaction; emotional impact of caring for a child at risk of anaphylaxis; and interaction with the health system and healthcare providers. Parents' information needs were categorized into themes relating to: gaps in knowledge and information; type of information desired; information sources; and information delivery format. Conclusion: Negative emotional experiences and a general lack of information were commonly reported by parents of included studies. Provision of relevant and comprehensible information may help parents to make informed decisions and manage reactions promptly. Innovation: The findings of this review are guiding the development of an innovative knowledge translation tool (KT) as part of a larger initiative of developing a suite of parent-focused KT tools for acute childhood conditions.

Risk factors and preventive interventions for post Covid-19 condition: systematic review.

This systematic review examined pre-existing and clinical risk factors for post Covid-19 condition (≥12 weeks after onset), and interventions during acute and post-acute phases of illness that could potentially prevent post Covid-19 condition. The review focuses on studies collecting data during the early phases of the pandemic and prior to the emergence of variants of concern and widespread vaccination. We searched bibliographic databases and grey literature. Two investigators independently reviewed abstracts and full-text articles, and data extraction and risk of bias assessments were verified. Meta-analysis was performed when suitable and we assessed the certainty of evidence using GRADE. We included 31 studies. We found small-to-moderate associations (e.g. adjusted odds ratios 1.5 to <2.0) between female sex and higher non-recovery, fatigue, and dyspnea (moderate certainty). Severe or critical acute-phase Covid-19 severity (versus not) has probably (moderate certainty) a large association (adjusted ratio ≥2.0) with increased cognitive impairment, a small-to-moderate association with more non-recovery, and a little-to-no association with dyspnea. There may be (low certainty) large associations between hospitalization and increased non-recovery, increased dyspnea, and reduced return to work. Other outcomes had low certainty of small-to-moderate or little-to-no association or very low certainty. Several potential preventive interventions were examined, but effects are very uncertain. Guidelines in relation to surveillance, screening, and other services such as access to sickness and disability benefits, might need to focus on females and those with previously severe Covid-19 illness. Continuous assessment of emerging evidence, especially on whether different variants and vaccination impact outcomes, will be important. PROSPERO registration: CRD42021270354.

Health inequities related to vaccination: An evidence map of potentially influential factors and systematic review of interventions.

INTRODUCTION: The National Advisory Committee on Immunization (NACI) makes recommendations for vaccines in Canada. To inform considerations for equity when making recommendations, the NACI Secretariat developed a matrix of factors that may influence vaccine equity. To inform the matrix we mapped the evidence for P2ROGRESS And Other factors potentially associated with unequal levels of illness or death from vaccine-preventable diseases (VPDs) and systematically reviewed the evidence for interventions aimed at reducing inequities. METHODS: In October 2019 we searched Medline, Embase, and CINAHL. Two reviewers agreed on the included studies. Our primary outcomes were VPD-related hospitalizations and deaths. Secondary outcomes were differential vaccine access, and exposure, susceptibility, severity, and consequences of VPDs. Two reviewers appraised the certainty of evidence. We mapped the evidence for P2ROGRESS And Other factors and summarized the findings descriptively. We summarized the interventions narratively. RESULTS: We identified 413 studies reporting on P2ROGRESS And Other factors. The most commonly investigated factors included age (n = 374, 89%), pre-existing conditions (n = 179, 42%), and gender identity or sex (n = 144, 34%). We identified 2 trials investigating the effects of interventions. One (n = 1249) provided very low certainty evidence that staff vaccination policies may reduce hospitalizations and deaths from influenza among private care home residents. The other (n not reported) provided very low certainty evidence that universal vaccination by nurses in clinics may reduce hospitalizations for rotavirus gastroenteritis compared with vaccination by physicians or no intervention. CONCLUSIONS: There is a large body of studies reporting on hospitalizations and deaths from VPDs stratified by P2ROGRESS And Other factors. We found only two trials examining the effects of interventions on hospitalization for or mortality from VPDs. This review has been helpful to NACI and will be helpful to similar organizations aiming to systematically identify and target health inequities through the development of vaccine program recommendations.

Risk factors for severity of COVID-19: a rapid review to inform vaccine prioritisation in Canada.

OBJECTIVES: Rapid review to determine the magnitude of association between potential risk factors and severity of COVID-19, to inform vaccine prioritisation in Canada. SETTING: Ovid MEDLINE(R) ALL, Epistemonikos COVID-19 in L·OVE Platform, McMaster COVID-19 Evidence Alerts and websites were searched to 15 June 2020. Eligible studies were conducted in high-income countries and used multivariate analyses. PARTICIPANTS: After piloting, screening, data extraction and quality appraisal were performed by a single experienced reviewer. Of 3740 unique records identified, 34 were included that reported on median 596 (range 44-418 794) participants, aged 42-84 years. 19/34 (56%) were good quality. OUTCOMES: Hospitalisation, intensive care unit admission, length of stay in hospital or intensive care unit, mechanical ventilation, severe disease, mortality. RESULTS: Authors synthesised findings narratively and appraised the certainty of the evidence for each risk factor-outcome association. There was low or moderate certainty evidence for a large (≥2-fold) magnitude of association between hospitalisation in people with COVID-19, and: obesity class III, heart failure, diabetes, chronic kidney disease, dementia, age >45 years, male gender, black race/ethnicity (vs non-Hispanic white), homelessness and low income. Age >60 and >70 years may be associated with large increases in mechanical ventilation and severe disease, respectively. For mortality, a large magnitude of association may exist with liver disease, Bangladeshi ethnicity (vs British white), age >45 years, age >80 years (vs 65-69 years) and male gender among 20-64 years (but not older). Associations with hospitalisation and mortality may be very large (≥5-fold) for those aged ≥60 years. CONCLUSIONS: Increasing age (especially >60 years) may be the most important risk factor for severe outcomes. High-quality primary research accounting for multiple confounders is needed to better understand the magnitude of associations for severity of COVID-19 with several other factors. PROSPERO REGISTRATION NUMBER: CRD42020198001.

A systematic review of factors that influence the acceptability of vaccines among Canadians.

BACKGROUND: Canada's National Advisory Committee on Immunization (NACI) provides guidance on the use of vaccines in Canada. To support the expansion of its mandate to include considerations for vaccine acceptability when making recommendations, the NACI Secretariat developed a matrix of factors that influence acceptability. To inform and validate the matrix, we systematically reviewed evidence for factors that influence vaccine acceptability, and for interventions aimed at improving acceptability. METHODS: On 10-11 October 2018 we searched four bibliographic databases, the Theses Canada Portal, and ClinicalTrials.gov. Two reviewers agreed on the included studies. From each study, we extracted information about the participants, intervention or exposure, comparator, and relevant outcomes. Due to heterogeneity in the reported factors and acceptability indicators we synthesized the findings narratively. We appraised the certainty of evidence using GRADE. For each vaccine-preventable disease we populated a matrix of factors for which there was evidence of an influence on acceptability. RESULTS: One hundred studies (>1 million participants) contributed data relevant to the public, 16 (6191 participants) to healthcare providers, and three (84 participants) to policymakers. There were 43 intervention studies (~2 million participants). Across vaccines, we identified low certainty evidence for 70 factors relevant to the general population, 56 to high-risk groups, and 30 to healthcare providers. The perceived safety and importance of the vaccine, vaccination history, and receiving a recommendation from a healthcare provider were common influential factors. We found low certainty evidence that reminders for childhood vaccines and policies or delivery models for rotavirus vaccines could improve uptake and coverage. Evidence for other interventions was of very low certainty. CONCLUSIONS: The NACI vaccine acceptability matrix is useful for categorizing acceptability factors for the general public. Reminder systems may improve the uptake of childhood vaccines. Policies that make the rotavirus vaccine universally available and easily accessible may improve coverage. FUNDING: This systematic review was completed under contract to the Public Health Agency of Canada, Contract #4600001536.

Fall prevention interventions for older community-dwelling adults: systematic reviews on benefits, harms, and patient values and preferences.

BACKGROUND: An estimated 20-30% of community-dwelling Canadian adults aged 65 years or older experience one or more falls each year. Fall-related injuries are a leading cause of hospitalization and can lead to functional independence. Many fall prevention interventions, often based on modifiable risk factors, have been studied. Apart from the magnitude of the benefits and harms from different interventions, the preferences of older adults for different interventions as well as the relative importance they place on the different potential outcomes may influence recommendations by guideline panels. These reviews on benefits and harms of interventions, and on patient values and preferences, will inform the Canadian Task Force on Preventive Health Care to develop recommendations on fall prevention for primary care providers. METHODS: To review the benefits and harms of fall prevention interventions, we will update a previous systematic review of randomized controlled trials with adaptations to modify the classification of interventions and narrow the scope to community-dwelling older adults and primary-care relevant interventions. Four databases (MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Ageline), reference lists, trial registries, and relevant websites will be searched, using limits for randomized trials and date (2016 onwards). We will classify interventions according to the Prevention of Falls Network Europe (ProFANE) Group's taxonomy. Outcomes include fallers, falls, injurious falls, fractures, hip fractures, institutionalization, health-related quality of life, functional status, and intervention-related adverse effects. For studies not included in the previous review, screening, study selection, data extraction on outcomes, and risk of bias assessments will be independently undertaken by two reviewers with consensus used for final decisions. Where quantitative analysis is suitable, network or pairwise meta-analysis will be conducted using a frequentist approach in Stata. Assessment of the transitivity and coherence of the network meta-analyses will be undertaken. For the reviews on patient preferences and outcome valuation (relative importance of outcomes), we will perform de novo reviews with searches in three databases (MEDLINE, PsycInfo, and CINAHL) and reference lists for cross-sectional, longitudinal quantitative, or qualitative studies published from 2000. Selection, data extraction, and risk of bias assessments suitable for each study design will be performed in duplicate. The analysis will be guided by a narrative synthesis approach, which may include meta-analysis for health-state utilities. We will use the CINeMa approach to a rate the certainty of the evidence for outcomes on intervention effects analyzed using network meta-analysis and the GRADE approach for all other outcomes. DISCUSSION: We will describe the flow of literature and characteristics of all studies and present results of all analyses and summary of finding tables. We will compare our findings to others and discuss the limitations of the reviews and the available literature. SYSTEMATIC REVIEW REGISTRATION: This protocol has not been registered.

Decoding semi-automated title-abstract screening: findings from a convenience sample of reviews.

BACKGROUND: We evaluated the benefits and risks of using the Abstrackr machine learning (ML) tool to semi-automate title-abstract screening and explored whether Abstrackr's predictions varied by review or study-level characteristics. METHODS: For a convenience sample of 16 reviews for which adequate data were available to address our objectives (11 systematic reviews and 5 rapid reviews), we screened a 200-record training set in Abstrackr and downloaded the relevance (relevant or irrelevant) of the remaining records, as predicted by the tool. We retrospectively simulated the liberal-accelerated screening approach. We estimated the time savings and proportion missed compared with dual independent screening. For reviews with pairwise meta-analyses, we evaluated changes to the pooled effects after removing the missed studies. We explored whether the tool's predictions varied by review and study-level characteristics. RESULTS: Using the ML-assisted liberal-accelerated approach, we wrongly excluded 0 to 3 (0 to 14%) records that were included in the final reports, but saved a median (IQR) 26 (9, 42) h of screening time. One missed study was included in eight pairwise meta-analyses in one systematic review. The pooled effect for just one of those meta-analyses changed considerably (from MD (95% CI) - 1.53 (- 2.92, - 0.15) to - 1.17 (- 2.70, 0.36)). Of 802 records in the final reports, 87% were correctly predicted as relevant. The correctness of the predictions did not differ by review (systematic or rapid, P = 0.37) or intervention type (simple or complex, P = 0.47). The predictions were more often correct in reviews with multiple (89%) vs. single (83%) research questions (P = 0.01), or that included only trials (95%) vs. multiple designs (86%) (P = 0.003). At the study level, trials (91%), mixed methods (100%), and qualitative (93%) studies were more often correctly predicted as relevant compared with observational studies (79%) or reviews (83%) (P = 0.0006). Studies at high or unclear (88%) vs. low risk of bias (80%) (P = 0.039), and those published more recently (mean (SD) 2008 (7) vs. 2006 (10), P = 0.02) were more often correctly predicted as relevant. CONCLUSION: Our screening approach saved time and may be suitable in conditions where the limited risk of missing relevant records is acceptable. Several of our findings are paradoxical and require further study to fully understand the tasks to which ML-assisted screening is best suited. The findings should be interpreted in light of the fact that the protocol was prepared for the funder, but not published a priori. Because we used a convenience sample, the findings may be prone to selection bias. The results may not be generalizable to other samples of reviews, ML tools, or screening approaches. The small number of missed studies across reviews with pairwise meta-analyses hindered strong conclusions about the effect of missed studies on the results and conclusions of systematic reviews.

Stay in or play out? The influence of weather conditions on physical activity of grade 5 children in Canada.

OBJECTIVES: Regular physical activity (PA) in children is essential for their development and prevention of overweight and obesity. Little is known about the effect of day-to-day variations in weather conditions on PA levels in school-aged children, particularly with regard to school compared to non-school days and girls compared to boys. METHODS: Daily step count (7:00 a.m.-9:00 p.m.) from 972 grade 5 students aged 10-11 years from 60 schools across Alberta, Canada, was collected using time-stamped pedometers (minimum wear time of two school and one non-school days) during March-June 2013. Time-matched weather conditions (actual and feels-like temperature, cloud coverage, and precipitation amount) were obtained from local weather stations in Alberta during the same period. Multilevel mixed-effect regression models were used to estimate the effect of each weather condition on daily step count. RESULTS: A 1 °C increase in feels-like temperature was associated with 26 more steps/day (p < 0.05), while 1-unit increase in cloud coverage was associated with 61 fewer steps/day (p < 0.01). Compared to no precipitation, heavy precipitation (> 5 mm/day) was associated with 1022 fewer steps/day (p < 0.01). Students' PA levels were associated with weather conditions more on non-school vs. school days and more among girls vs. boys. CONCLUSION: Results suggest that daily weather conditions can affect PA in school children, particularly outside school hours, and should be considered when evaluating PA levels or designing interventions to promote PA in children. Findings provide support for increased investment toward creating weather-appropriate physical activity opportunities for wet and colder days to prevent PA decline in children during inclement weather conditions.