Parent engagement in co-design of clinical trials: the PARENT trial

Evidence generated from partnering with parents to design and conduct research together may be used to refine, adjust, and modify future research approaches. This study aimed to describe the initial approaches to parent engagement in the design of the PARENT trial as well as understand parent perspectives on the acceptability and relevance of the PARENT trial and potential barriers and facilitators to participation.Parents participating in the TARGet Kids! cohort were invited to participate in a focus group, called the PARENT panel, to co-design the PARENT trial. This focus group was conducted to capture diverse individual and collective parents' experiences. Overall methodological approaches for the PARENT panel were informed by the CIHR Strategy for Patient Oriented Research (SPOR) guiding principles (mutual respect, co-building, inclusiveness, and support) for patient engagement in research, and facilitated through the Knowledge Translation Program in the Li Ka Shing Knowledge Institute at Unity Health Toronto. Using a Nominal Group Technique, the PARENT panel provided feedback on the feasibility, relevance, and acceptability of the proposed intervention. Findings from this work will be used to further refine, adjust, and modify the next iteration of the PARENT trial, which will also serve as an opportunity to discuss the efforts made by researchers to incorporate parent suggestions and what additional steps are required for improved patient engagement.

Clustered longitudinal data subject to irregular observation

Data collected longitudinally as part of usual health care is becoming increasingly available for research, and is often available across several centres. Because the frequency of follow-up is typically determined by the patient's health, the timing of measurements may be related to the outcome of interest. Failure to account for the informative nature of the observation process can result in biased inferences. While methods for accounting for the association between observation frequency and outcome are available, they do not currently account for clustering within centres. We formulate a semi-parametric joint model to include random effects for centres as well as subjects. We also show how inverse-intensity weighted GEEs can be adapted to account for clustering, comparing stratification, frailty models, and covariate adjustment to account for clustering in the observation process. The finite-sample performance of the proposed methods is evaluated through simulation and the methods illustrated using a study of the relationship between outdoor play and air quality in children aged 2-9 living in the Greater Toronto Area.

How to increase the value of self-reported health service data by using data linkage: a case study

Background

This is a case study for recurrent stroke prevention. Lifestyle factors account for about 80% of the risk of recurrent stroke. Most health services studies examining stroke prevention rely on stroke survivors' self-reported lifestyle behaviour data. How can researchers increase the value of collected self-reported data to provide additional information for more comprehensive assessments?

Methods

45 and Up Study is the largest ongoing study in the Southern Hemisphere focusing on the health of people aged 45 years and older living in NSW, Australia. This case study linked self-reported longitudinal lifestyle data in the 45 and Up Study, with corresponding mortality data (i.e. NSW Registry of Births, Deaths and Marriages & NSW Cause of Death Unit Record File) and hospital data (i.e. NSW Admitted Patient Data Collection) via the Centre for Health Record Linkage (CHeReL). The main outcome measures are health services, clinical outcomes, and mortality rates for stroke care. The analyses will include descriptive analysis, multivariate regression analysis, and survival analysis.

Results

A total of 8410 stroke survivors who participated in the 45 and Up Study were included in this data linkage study. From January 2006 to December 2015, 99249 hospital claims (mean: 13 times admission to hospital per person) and 2656 death registration records have been linked to these participants. The mean age of the stroke survivors was 72 (SD = 11) years, with 56% being males. These results are preliminary and more analyses will be conducted by using quality of life status, clinical diagnosis, comorbidities, and procedures.

Conclusions

Data linkage enables researchers to generate comprehensive findings on health services studies and gain a more holistic understanding of the determinants and outcomes of stroke prevention with lower data collection costs and less burden on participants.

Key messages

Data linkage brings about a new opportunity for self-reported data on health services utilisation. It is a cost-effective way to enhance existing self-reported data via the data linkage approach to increase its usefulness for informing health service planning.

114 Distributional Decomposition: A Novel Method for Understanding Inequities in Child Growth, Behavior and Development

Background

Income related inequities in child health are well-established, with children from lower income households showing increased risk of obesity, behavior problems, and delayed development. To facilitate clinical diagnosis, outcomes are conventionally measured in dichotomous terms. However, inequities may exist along the entire range of distribution, with implications for population health.

Objectives

Our primary objective was to examine differences in the distribution of three measures of child health by income: body mass index (BMI), behavior difficulties and development.

Design/Methods

This was a cross sectional study of children enrolled in a primary care practice-based research cohort. Our study included generally healthy children recruited from age 0-5 years. Dependent variables were 1) BMI z-score (zBMI) at 5 years; 2) behavior: total score on the Strengths and Difficulties Questionnaire (SDQ), measured at 3-5 years; 3) development: total score on the Infant Toddler Checklist (ITC), measured at 18-24 months. Independent variable was parent-reported annual household income (< $100,000 vs ≥ $100000). We then used distributional decomposition, which uses mathematical re-weighting to construct a counterfactual distribution that describes the distribution of the lower income group based on the predictor profile (child age, sex, birthweight, prematurity, breastfeeding duration; maternal age, education, immigration status, ethnicity) of the higher income group.

Results

Our study samples consisted of 1649 (zBMI), 764 (SDQ) and 761 (ITC) children. Mean BMI z-score was 0.16, median total difficulties score was 7, median ITC score was 48. Comparing distributions graphically (Figure 1), children with low income have a higher risk distribution for all outcomes; for example, children with low income were more likely to have BMI z-scores in the underweight and obese ranges. For each outcome, the counterfactual curve lower income children with the predictor profile of their higher income counterparts reduced inequities somewhat, particularly in the normal or low risk range, but not in the high-risk range. However, there were notable unexplained portions of inequity remaining.

Conclusion

In a cohort of generally healthy children, we found evidence of meaningful income-related inequities in the distribution of child zBMI, behavior difficulties, and development. Population health interventions aiming to mitigate these inequities by addressing common predictors may improve outcomes in the normal range; however targeted clinical interventions are likely required for those in the high-risk range.

61 Cow’s milk fat and child adiposity: a prospective cohort study

Background

International guidelines recommend that children older than 2 years of age consume reduced fat (0.1-2%) instead of whole cow’s milk (3.25% fat) to prevent childhood obesity, but these guidelines are consensus-based and have a low GRADE level of evidence.

Objectives

The primary objective of this study was to evaluate the longitudinal relationship between cow’s milk fat (0.1-3.25%) intake and Body Mass Index z-score (zBMI) in children aged 9 months to 8 years. The secondary objective was to determine the relationship between cow’s milk fat intake and odds of overweight (zBMI >1) and obesity (zBMI > 2).

Design/Methods

A prospective cohort study of children 9 months to 8 years of age was conducted through the TARGet Kids! primary care research network. The primary exposure was cow’s milk fat consumption (skim (0.1%), 1%, 2%, or whole [3.25%]), measured by parental report. The primary outcome was zBMI, an age and sex adjusted measure of child adiposity. Height and weight were measured by trained research assistants and zBMI was determined according to the WHO growth standards. A linear mixed effects model and logistic generalized estimating equations were used to determine the longitudinal association between cow’s milk fat intake and child zBMI.

Results

Among children aged 9 months to 8 years of age (N= 7467), each 1% increase in cow’s milk fat consumed was associated with a 0.05 lower zBMI score (95% CI -0.07 to -0.03, p< 0.0001). Compared to children who consumed reduced fat (0.1-2%) cow’s milk, there was evidence that children who consumed whole cow’s milk had 16% lower odds of overweight (OR=0.84, 95% CI 0.77 to 0.91), p< 0.0001) and 18% lower odds of obesity (OR= 0.82, 95% CI 0.68 to 1.00, p= 0.047).

Conclusion

Guidelines for reduced fat instead of whole cow’s milk during childhood may not be effective in preventing overweight or obesity. Randomized controlled trial data is needed to understand which cow’s milk fat optimizes child growth, development and nutrition.

73 Sleep Duration and Internalizing Symptoms in Children

Background

Emotional problems such as anxiety and low mood have been associated with sleep problems in children.

Objectives

This study’s objective was to assess the association between sleep duration and internalizing symptoms in children age 5-12 years (y). Next, we evaluated whether meeting the National Sleep Foundation’s guidelines for sufficient sleep (≥10 hours, age 3-5; ≥9, age 6-12) is associated with internalizing symptoms.

Design/Methods

A cross-sectional study in N = 800 healthy children ages 5-12y, recruited from primary care physicians’ offices in Toronto, Canada was conducted through TARGet Kids! research network. Using linear regression, we investigated the association between parent reported sleep duration (hours) and parent reported internalizing symptoms using the Strengths and Difficulties Questionnaire (SDQ), controlling for child age, sex, zBMI, family composition, and maternal education.

Results

The adjusted model showed an inverse association between sleep duration and internalizing symptoms (β estimate = -0.33 (95%CI -0.57, -0.07), p=0.011). Of children aged 6-12y, 36 (6%), and of those aged 5y, 28 (14%) did not meet guidelines for sufficient sleep. Insufficient sleep was inversely associated with internalizing symptoms (β estimate = -0.70 (-1.38, -0,02), p=0.044). However, the association attenuated slightly once adjusted for child age, sex, zBMI, family composition, and maternal education (β estimate = -0.64 (-1.38, 0.10), p=0.088).

Conclusion

There is evidence that a parent reported decrease in sleep of 3 hours is associated with a small (1 point) increase on the internalizing scale in children between 5 and 12 years. The primary limitation is that sleep duration and internalizing symptoms were reported by parents.

88 Vegetarian diet, growth and micronutrient stores in childhood: A prospective cohort study

Background

Vegetarian diets are becoming increasingly popular among Canadians, yet few studies have evaluated the relationship between a vegetarian diet and childhood growth and nutritional status. Since vegetarian diets can be less energy dense and may have lower micronutrient content, we hypothesized that a vegetarian diet may affect childhood growth including lower adiposity and height, as well as lower micronutrient stores.

Objectives

The primary objective of this study was to evaluate the relationship between vegetarian diet and growth, including adiposity and height among healthy children 6 months to 10 years of age. Secondary objectives included the examination of the relationship between vegetarian diet and iron and vitamin D stores. We also explored whether cow’s milk intake or age modified the associations between vegetarian diet and growth, and micronutrient stores.

Design/Methods

This was a prospective cohort study of healthy children age 6 months to 10 years. The primary exposure was vegetarian diet measured by parent report. The primary outcome was BMI z-score. Secondary outcomes included height-for-age z-score, serum ferritin, and serum 25-hydroxyvitamin D. Anthropometric measures and venous blood samples were collected at health supervision visits by trained research assistants. Linear mixed effect modelling was used to determine the association between vegetarian diet, growth, and micronutrient stores.

Results

A total of 8912 children (n = 248 vegetarian) participated. In the adjusted models there was no evidence of an association between vegetarian diet and BMI z-score (p = 0.605, 95% CI: -0.06, 0.10), height-for-age z-score (p 0.057, 95% CI: -0.16, 0.002), serum ferritin (p = 0.768, 95% CI: -3.84, 2.84), or 25-hydroxyvitamin D (p = 0.204, 95% CI: -2.14, 0.46). The relationship between vegetarian diet and serum 25-hydroxyvitamin D was modified by child age. Volume of cow’s milk intake did not modify the relationships between vegetarian diet and BMI z-score, height-for-age z-score, serum ferritin, or 25-hydroxyvitamin D. In a secondary analysis, we examined adiposity through weight status categories and found children with a vegetarian diet had higher odds of being underweight (BMI z-score <-2) (OR 1.9, p = 0.006, 95% CI 1.21-3.00).

Conclusion

In this prospective cohort study, evidence of an association between vegetarian diet and lower BMI z-score, height-for-age z-score, and micronutrient stores was not found. Our results suggest children with vegetarian diets had higher odds of being underweight. Future research is needed to evaluate dietary factors and patterns of children following vegetarian diets, especially those with an underweight weight status.

Outlier Detection in Growth Data: Beyond Biologically Implausible Values

Objectives

Eliminating anthropometry measurement error and employing outlier and biological implausible values (BIV) detection methods adapted to longitudinal measurements is important for the study of growth. This work aimed to review and assess the accuracy of the available BIV and outlier detection methods and propose a growth trajectory outlier detection method.

Methods

We included 2354 infants from the Applied Research Group for Kids (TARGet Kids! ) cohort-based in Toronto (ON, Canada) that recruits healthy children from birth to 5 years of age. We considered infants with at least 8 length and weight measurements available between the 1st and the 24th month of age. Weight-for-length z-scores (wflz) were calculated using the WHO growth standards. Outlier measurements were randomly introduced in 5% of the wflz measurements using a normal distribution (μ = 0, σ = 1). We employed 4 outlier detection methods; an empirical detection method for BIV using the cut-offs derived from the WHO Child Growth Standards, a clustering method, a method based on cluster prototypes for individual outlier measurements and a method based on cluster prototypes for entire growth trajectories. Each method was applied individually and evaluated using the sensitivity and specificity indexes based on the manually introduced outliers. We also calculated the Kappa statistic to evaluate the agreement of each method against the manual outliers.

Results

After excluding premature (<37 weeks), low birth weight (<1500 g) neonates and children with missing length and weight measurements, we analyzed 393 children with a total of 3144 measurements. Sensitivity and specificity for the four methods ranged between 4.4%–55.0% and 83.7% −99.7%, respectively, with kappa being non-significant (P > 0.05) only for the empirical. The clustering detection method reported a higher finding rate, while the empirical method found most of the BIV, but few of the rest of the outliers.

Conclusions

BIV account for a small portion of the possible outliers in growth datasets. We show that additional statistical or model-based methods are required for a more comprehensive outlier detection process, which has implications for growth analysis and nutritional assessment.

Funding Sources

Joannah and Brian Lawson Center for Child Nutrition, Connaught Fund, Onassis Foundation.

Core outcome set for children with neurological impairment and tube feeding

AIM

To develop a core outcome set (COS) for evaluating gastrostomy/gastrojejunostomy tube impact in children with neurological impairment.

METHOD

Healthcare providers/researchers and caregivers rated the importance of candidate outcomes on a 5-point Likert scale. Outcomes rated 'somewhat important' or 'very important' by most (≥85%) respondents were voted on during a consensus meeting. Outcomes that reached consensus for inclusion were ratified and assigned to Outcome Measures in Rheumatology filter core areas. The COS was validated in a separate group of caregivers.

RESULTS

Twelve outcomes were selected from 120 candidate outcomes to form the COS. These included five 'Life Impact' outcomes, three 'Pathophysiological Manifestations' outcomes, two 'Resource Use' outcomes, one 'Growth and Development' outcome, and one 'Death' outcome.

INTERPRETATION

We developed an evidence-informed and consensus-based COS for use in studies of gastrostomy/gastrojejunostomy tube feeding in children with neurological impairment. Implementation of this COS will help reduce heterogeneity between studies and facilitate evidence-based decision-making.

WHAT THE PAPER ADDS

Caregivers, healthcare providers, and researchers ranked the importance of 120 outcomes. Twelve core outcomes were identified as essential to measure in future clinical research studies.

Effect of Vitamin D supplementation to reduce respiratory infections in children and adolescents in Vietnam: A randomized controlled trial

Background

It is uncertain whether vitamin D can reduce respiratory infection.

Objective

To determine whether vitamin D supplementation reduces influenza and other upper viral respiratory tract infections.

Methods

A total of 1300 healthy children and adolescents between the ages of 3 and 17 years were randomized to vitamin D (14 000 U weekly) or placebo for 8 months in Vietnam. The primary outcome was reverse transcriptase (RT)‐PCR–confirmed influenza infection, and the coprimary outcome was multiplex PCR–confirmed non‐influenza respiratory viruses. Participants, caregivers, and those assessing outcomes were blinded to group assignment.

Results

A total of 650 children and adolescents were randomly assigned to vitamin D and 650 to placebo. The mean baseline serum 25‐hydroxyvitamin D levels were 65.7 nmol/L and 65.2 nmol/L in the intervention and placebo groups, respectively, with an increase to 91.8 nmol/L in the vitamin D group and no increase, 64.5 nmol/L, in the placebo group. All 1300 participants randomized contributed to the analysis. We observed RT‐PCR–confirmed influenza A or B occurred in 50 children (7.7%) in the vitamin D group and in 43 (6.6%) in the placebo group (hazard ratio [HR]: 1.18, 95% CI: 0.79‐1.78). RT‐PCR–confirmed non‐influenza respiratory virus infection occurred in 146 (22.5%) in the vitamin D group and in 185 (28.5%) in the placebo group (hazard ratio [HR]: 0.76, 95% CI: 0.61‐0.94). When considering all respiratory viruses, including influenza, the effect of vitamin D in reducing infection was significant, HR: 0.81, 95% CI: 0.66‐0.99.

Conclusion

Vitamin D supplementation did not reduce the incidence of influenza but moderately reduced non‐influenza respiratory viral infection.

Vitamin D Level and Supplementation in Pediatric Atopic Dermatitis: A Randomized Controlled Trial

BACKGROUND:

Atopic dermatitis (AD) is a chronic inflammatory skin condition characterized by a pruritic eczematous rash. Evidence surrounding the role of serum vitamin D (VD) in modifying disease severity is inconsistent.

OBJECTIVES:

To determine whether VD levels are correlated with AD severity and the effects of VD supplementation on disease modification.

METHODS:

This was a 2-phase study, using a cross-sectional design to evaluate the relationship between VD level and severity, as well as a double-blinded, randomized control trial to elucidate the effects of VD supplementation. Patients aged 0 to 18 years with AD were included in phase 1, and disease severity and serum VD levels were determined. Those with renal, liver, or other dermatologic conditions were excluded. Patients with abnormal (<72.7 nmol/L) VD levels were eligible for phase 2 and to be randomized to either VD supplementation of 2000 IU/d or placebo. VD level and severity were assessed at baseline and 3 months.

RESULTS:

The 77 patients included in phase 1 had a mean (SD) age of 7.4 (4.5) years, and 45.5% (33/77) were female. Increased severity was significantly correlated with lower VD levels ( P = .015). Of the 45 patients included in phase 2, 21 and 24 were assigned to the supplementation and placebo arm, respectively. The mean (SD) change in severity did not differ significantly between the supplementation (15.35 [9.71]) and placebo (15.13 [8.97]) groups after 3 months of intervention ( P = .7).

CONCLUSION:

Although VD levels correlated with AD severity, VD supplementation did not significantly improve disease severity.

Comparing two asthma diagnoses using a prospective cohort of young children

IntroductionAsthma is the most common chronic illness of childhood and places a large burden on the health care system. Asthma prevalence is commonly measured in national surveys by questionnaire. In Ontario, the Ontario Asthma Surveillance Information System (OASIS) developed a validated health claims diagnosis algorithm using health administrative data. Objectives and ApproachThe primary objective of this study was to measure the agreement between the health claims diagnosis algorithm (OASIS diagnosis algorithm) and questionnaire diagnosis (TARGet Kids! diagnosis) of asthma in children younger than 6 years of age. Secondary objectives were to identify concordant and discordant pairs, and to identify factors associated with disagreement. A comparison study including 3368 children participating in the TARGet Kids! practice based research network between 2008 and 2013 in Toronto, Canada. OASIS diagnosis algorithm and TARGet Kids! diagnosis asthma cases were compared using kappa statistic, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). ResultsPrevalence of asthma was estimated to be 15% by the OASIS diagnosis algorithm and 7% by TARGet Kids! diagnosis. The Kappa statistic was 0.47 (95% CI: 0.42 – 0.51), sensitivity 82\%, specificity 90%, PPV 38% and NPV 98% for OASIS diagnosis algorithm using TARGet Kids! diagnosis as the criterion standard. There were 3011 concordant pairs (2820 true negatives and 191 true positives) and 357 discordant pairs (315 false positives and 42 false negatives). Statistically significant factors associated with false positives included: male sex, higher zBMI and history of allergy. No statistically significant factors associated with false negatives were identified. Conclusion/ImplicationsOASIS diagnosis algorithm had high sensitivity, specificity, and NPV but low PPV relative to TARGet Kids! diagnosis of asthma. Although, the OASIS diagnosis may identify more asthma cases in young children, its diagnostic properties are similar in older children and it may be a useful tool for longitudinal asthma surveillance.

25-hydroxyvitamin D and health service utilization for asthma in early childhood

IntroductionAsthma is the most common chronic illness of childhood and a common reason for hospital admission. Studies suggest that low vitamin D levels may be associated with health service utilization (HSU) for childhood asthma. Objectives and ApproachThe primary objective was to determine if vitamin D serum levels in early childhood were associated with HSU for asthma including: a) total HSU, b) hospital admissions, c) emergency department visits and d) outpatient sick visits. Secondary objectives were to determine whether vitamin D supplementation in pregnancy or childhood were associated with HSU for asthma. Prospective cohort study of children participating in the TARGet Kids! practice based research network. HSU was determined by linking each child's provincial health insurance number to health administrative databases. Multivariable quasi Poisson and logistic regression were used to evaluate the associations. Results2926 healthy children ages 0-6 years had 25-hydroxyvitamin D data available and were included in the primary analysis. Mean (IQR) 25-hydroxyvitmain D level was 84 nmol/L (65-98 nmol/L), 218 and 1267 children had 25-hydroxyvitamin D levels <50 nmol/L and <75 nmol/L, respectively. In the adjusted models, there were no associations between 25-hydroxyvitamin D (continuously or dichotomized at 50 and 75 nmol/L), vitamin D supplementation in pregnancy or childhood and HSU for asthma. Conclusion/ImplicationsHigher vitamin D blood values do not appear to be associated with HSU for asthma in this population of healthy urban children.

Survival to Stage II with Ventricular Dysfunction: Secondary Analysis of the Single Ventricle Reconstruction Trial

Ventricular dysfunction affects survival in patients with single right ventricle (RV), and remains one of the primary indications for heart transplantation. Since it is challenging to predict the capacity of patients with ventricular dysfunction to proceed to the stage II procedure, we sought to identify factors that would be associated with death or heart transplantation without achieving stage II for single RV patients with ventricular dysfunction after Norwood procedure. The Single Ventricle Reconstruction (SVR) trial public-use database was used. Patients with a RV ejection fraction less than 44% or a RV fractional area of change less than 35% on the post-Norwood echocardiogram were included. Parametric risk hazard analysis was used to identify risk factors for death or transplantation without achieving stage II. Of 365 patients with ventricular function measurements on the post-Norwood echocardiogram, 123 (34%) patients had RV dysfunction. The transplantation-free survival was significantly lower for those with ventricular dysfunction compared to those with normal function (log rank Chi-square = 4.23, p = 0.04). Furthermore, having a Blalock-Taussig (BT) shunt, a large RV, a post-Norwood infectious complication, and a surgeon who performs five or less Norwood per year were independent risk factors for death or transplantation without achieving stage II. The predicted 6-month transplantation-free survival for patients with all four identified risk factors was 1% (70% CI 0-13%). Early heart transplantation referral might be considered for post-Norwood patients with BT shunt and RV dysfunction, especially if other high-risk features are present.