Fidelity And Compliance Of A Comprehensive Intervention For Childhood Obesity

【Objective】To assess the fidelity and compliance of a comprehensive intervention for childhood obesity,and to analyze its association with changes in obesity-related indicators,and to explore the factors influencing compliance of the intervention.【Methods】This study was based on a comprehensive intervention project for childhood obesity [The Diet,Exer CIse and Car Diovascular h Ealth(DECIDE)-Children study].A total of 686 children who received the comprehensive intervention for obesity in 20 classes from 12 schools in Beijing,Changzhi of Shanxi and Urumqi of Xinjiang were included for the analyses.Children’s basic information,obesity-related indicators before and after the intervention,fidelity and compliance during the school year were collected by questionnaire survey,physical examination,fidelity and compliance records.Mean ±standard deviation was used to describe continuous variables in accordance with normal distribution.Median(lower quartile,upper quartile)was used to describe the continuous variables that were not normally distributed.The number of cases(percentage)was used to describe the categorical variables.The association between fidelity/compliance and changes in obesity-related indicators was analyzed using a generalized linear mixed model(the dependent variable was a categorical variable)or a linear mixed model(the dependent variable was a continuous variable).Univariate and multivariate Logistic regression models were used to analyze the factors influencing compliance.【Results】1.Fidelity and compliance(1)FidelityFidelity of the DECIDE-Children project differed among schools and classes.Fidelity also differed across intervention measures: the fidelity of school-level intervention measures was 100.00%;the fidelity of parental and students’ health education sessions were better with the median fidelity higher than 98.00%;the fidelity of students’ physical activity within school was poorer,among which only a median of 50.00% recess/morning exercises meeting the standard,while the median fidelity of other indicators of students’ physical activity within school was higher than 75.00%;the fidelity of weight monitoring was better with the median fidelity higher than 99.00%.(2)ComplianceThe compliance of children’s dietary and exercise behaviors was good.The median score of compliance was 31.55 points(the total score was 35.00 points),in which the scores of diet behaviors were all over 4.50 points(The total score was 5.00 points),the median score of screen time was 4.45 points(the total score was 5.00 points),and the compliance of home exercise was slightly poor,with a median score of 3.57 points(the total score was 5.00 points).The compliance of APP use was good,with the median of 66 click times and 37.54 minutes of use,among which the click times of feedback and information dissemination were higher,while the behavior monitoring and homework uploading was longer.2.Association between fidelity and changes in obesity-related indicatorsCompared with the group with the lowest total score of fidelity,the percentage of overweight and obesity in the group with the highest total score of fidelity was 72.4% lower[Odds Raito(OR): 0.276;95% Confidence Interval: 0.098～0.775;P=0.015].No association was found between single fidelity indicators and BMI(all P value>0.05).No association was found between the total score of fidelity and the changes in BMI,BMI Z score,waist circumference,body fat percentage and percentage of obesity from baseline to the end of the intervention(all P values>0.05).3.Association between compliance and changes in obesity-related indicators(1)Association between the compliance of dietary and exercise behaviors and changes in obesity-related indicatorsCompared with the group with a lower score of compliance of dietary and exercise behaviors,percentage of obesity and percentage of overweight and obesity in the group with a higher score were reduced after the intervention by 68.2%(OR: 0.318;95% CI: 0.156～0.651;P=0.002),and54.1%(OR: 0.459;95% CI: 0.261～0.806;P=0.007),respectively.No association was found between single indicators of compliance of dietary and exercise behaviors and BMI(all P values > 0.05).No association was found between the total score of compliance of dietary and exercise behaviors and the changes in BMI,BMI Z score,waist circumference and body fat percentage from baseline to the end of the intervention(all P values > 0.05).(2)Association between compliance of APP use and changes in obesity-related indicatosResults from the analyses of the associations between the compliance of use of each APP module and BMI showed that in the three modules of behavior monitoring,homework uploading and feedback,the more of BMI decreased,the better improvement of compliance of APP use after the intervention(all P values < 0.05).Compared with the group with the least APP click times,BMI [Regression Coefficient(β):-0.335;95% CI:-0.524～-0.146],BMI Z score(β:-0.139;95% CI:-0.217～-0.062),waist circumference(β:-1.159;95% CI:-1.883～-0.435)and body fat percentage(β:-0.843;95% CI:--1.545～-0.140)in the group with the most APP click times decreased after intervention,and the difference between groups was statistically significant(all P values <0.05).There was a tendency that the higher of the APP click times,the greater of BMI,BMI Z score,waist circumference and body fat percentage was reduced(all P value < 0.05).Compared with the group with a lower APP click times,the group with a higher click times reduced the percentage of overweight and obesity after the intervention by 58.3%(OR: 0.417;95% CI: 0.235～0.739;P=0.003).No association was found between APP click times and percentage of obesity(P value>0.05).Compared with the group with the shortest APP use time,BMI(β:-0.244;95% CI:-0.436～-0.052)and waist circumference(β:-1.089;95% CI:-1.819～-0.359)in the group with the longest APP use time decreased after the intervention,and BMI Z score in the group with the longest(β:-0.105;95% CI:-0.183～-0.027)and second longest(β:-0.084;95% CI:-0.161～-0.007)APP use time decreased after the intervention,and the difference between groups were statistically significant(all P values < 0.05).There was a tendency that the more time spent in APP,the greater BMI,BMI Z score and waist circumference decreased after the intervention(all P values < 0.05).Compared with the group with a shorter APP use time,the percentage of overweight and obesity in the group with a longer use time was reduced after the intervention by 45.5%(OR: 0.545;95% CI: 0.311～0.956;P=0.034).No association was found between APP use time and percentage of obesity(P value>0.05).4.Influencing factors of compliance(1)Influencing factors of compliance of dietary and exercise behaviorsMultivariate analysis showed that after adjusting for other influencing factors,Beijing area,pre-intervention nutritional status of overweight and obesity and mothers’ high education level were the influencing factors for children’s low scores of compliance of dietary and exercise behaviors,while older fathers were more likely to improve children’s compliance of dietary and exercise behaviors.(2)Influencing factors of compliance of APP useMultivariate analysis showed that after adjusting for other influencing factors,Changzhi area,mothers as the primary caregiver,and older parents were the influencing factors for better compliance of APP use,and mothers who had a job were associated with less APP use.【Conclusions】The overall fidelity of the DECIDE-Children study was good,and all schools agreed to implement the intervention and most of the interventions were delivered as planned,which was better than or as similar as previous studies.The compliance of the subjects was good,which showed that the design of the intervention was reasonable,and the method of using mobile APP in the intervention was feasible.The compliance of APP use was related to changes of obesity-related indicators after the intervention,indicating that active use of mobile APP in the intervention was an important factor for the improvement of obesity-related indicators.Compliance was affected by a variety of factors of children and their families.Targeted measures should be taken for the specific population in the future obesity intervention project,so as to improve the compliance of the research subjects.