HEALTH STATUS OF EXTREMELY LOW BIRTH WEIGHT CHILDREN AT AGE 8 YEARS: CHILD AND PARENT PERSPECTIVE

doi:10.1001/archpediatrics.2011.149

Arch Pediatr Adolesc Med. Author manuscript; available in PMC 2013 February 18.

Published in final edited form as:

Arch Pediatr Adolesc Med. 2011 October; 165(10): 922–927.

doi: 10.1001/archpediatrics.2011.149

PMCID: PMC3575169

NIHMSID: NIHMS439620

HEALTH STATUS OF EXTREMELY LOW BIRTH WEIGHT CHILDREN AT AGE 8 YEARS: CHILD AND PARENT PERSPECTIVE

Maureen Hack, MB., ChB,¹ Christopher B Forrest, MD., PhD,² Mark Schluchter, PhD,³ H. Gerry Taylor, PhD,¹ Dennis Drotar, PhD,³ Grayson Holmbeck, PhD,⁴ and Laura Andreias, MD, MS¹

¹Department of Pediatrics, Case Western Reserve University, Cleveland, Ohio

²Children’s Hospital of Philadelphia, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania

³Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio

⁴Cincinnati Children’s Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio

⁴Department of Psychology, Loyola University, Chicago, Illinois

Corresponding author: Dr. Maureen Hack, Rainbow Babies and Children’s Hospital, University Hospitals of Cleveland Case, Medical Center, 11100 Euclid Avenue, Cleveland, Ohio 44106-6010, Telephone: 216-368-3744, Fax: 216-844-3380, Email: mxh7/at/case.edu

The publisher's final edited version of this article is available at Arch Pediatr Adolesc Med

Abstract

Context

Parental proxy reports have indicated poorer health for preterm children as compared to normal birth weight controls. The perspective of their children may however differ.

Objective

To compare the self reported health of preterm children to normal birth weight controls and the children’s perspective to that of their parents.

Design

Study of extremely low birth weight (<1kg) and normal birth weight children and their parents conducted 2006–2009.

Setting

Children’s hospital.

Participants

Eight year old extremely low birth weight (n=202) and normal birth weight (n=176) children of similar sociodemographic status.

Main Outcome Measures

The Child Health and Illness Profile child and parent reports.

Results

There was poor agreement between the parent and child ratings of health for both the extremely low birth weight and normal birth weight cohorts. Extremely low birth weight children rated their health similar to normal birth weight children. In contrast parents of extremely low birth weight children reported significantly poorer health for their children than parents of normal birth weight controls including poorer Satisfaction with health, Comfort and Achievement and less Risk avoidance.

Conclusion

There is poor agreement between child and parent reports of health. Eight year old extremely low birth weight children rate their health similar to that of normal birth weight controls. Their parents however report significantly poorer health. Both child and parent perspective needs to be considered when making health care decisions.

Reports of the long term outcomes of extremely low birth weight and gestational age children have focused on assessments of neurodevelopmental outcomes and behavior. The few studies of health status during the school age years have been based mainly on parental proxy report.^1–3 These have indicated that preterm children have a poorer health status than term born controls including poorer performance in physical, emotional and social functioning. However parental proxy reports provide an incomplete view of children’s health as parents may be unaware of their children’s internal feelings of health and well-being.^4–7 To date, the only information on the self-perception of the health of preterm children pertains to adolescents.^8–11 There have been no studies at earlier ages despite evidence that children as young as 7 to 8 years understand health concepts, are able to provide reliable responses to a health survey, and accurately respond to a four week recall period for symptoms or behaviors.^12–14

As part of a longitudinal study we sought to examine the self reported health experiences at age 8 years of extreme low birth weight [ELBW, <1Kg] compared to those of normal birth weight (NBW) controls and to compare the children’s perceptions to those of their parents.^15–19 For this purpose we used the Child Edition of the Child Health and Illness Profile (CHIP-CE), a multidimensional instrument with both child self-report and parent proxy forms.^20,21 The CHIP-CE includes a broad set of measures that assess satisfaction with one’s health and self, symptoms and limitations due to illness, psychosocial resiliencies, avoidance of risk behaviors, and achievement in school and with friends. We hypothesized that the children’s perception of their health would be more positive than that of their parents and that their perceptions of health would be determined by biologic risk as evidenced by birth weight (ELBW) status and by sociocdemographic risk factors with both having a negative effect on health.

METHODS

Extremely Low Birth Weight Cohort

The study population included 344 ELBW children admitted to the Neonatal Intensive Care Unit at Rainbow Babies and Children’s Hospital, Cleveland, Ohio between 1992 and 1995. Thirteen children (10 major congenital malformations, two with AIDS and one with Tuberous Sclerosis) were excluded. Of the remaining 331 children 238 (72%) survived of whom 219 (92%) were followed to 8 years.^15,22 Seventeen ELBW children did not complete the CHIP-CE questionnaire (15 were unable to comprehend the questions and two completed only one domain). These children had a mean IQ of 49 ±11, 10 had cerebral palsy and one was autistic.²³ The present report thus includes 202 ELBW children and their parents who responded to the CHIP-CE questionnaire. The 202 participants had significantly (p<0.05) lower rates of cerebral palsy (10% vs 59%) and subnormal IQ (<85, 33% vs 100%) and fewer boys (38% vs 71%) than the 17 non-participants but did not differ in caregiver education (13% vs 0% < high school) or race (61% vs 35% black).

Comparison Group of Normal Birth Weight Children

A control group of normal birth weight children (NBW, >36 weeks gestation by parent report) was recruited at 8 years by randomly selecting a child from a list of children in the same school as the ELBW child who was within 3 months of age and of the same race and sex as the ELBW child. Controls were recruited for 176 (80%) of the ELBW children, all of whom responded to the CHIP-CE questionnaire.¹⁵

Measures and Variables

Eight Year Study Protocol

The primary caregiver, usually the mother, and child were interviewed and the child underwent physical and neurological examinations and psychometric testing including the Kaufman Assessment Battery for Children (K-ABC) Mental Processing Composite (MPC) to measure cognitive function.²³ The results have been reported.^15–19

The primary outcome measure of this report, the CHIP-CE, measures the health of children from 6 to 11 years of age from the perspective of both the child and parent. It includes reports of feelings, symptoms, well-being, health related behaviors, problem behavior, school performance, and connectedness with family and peers.^20,21 It uses the same conceptual framework of the adolescent self-report instrument, the CHIP-AE.²⁴ The majority of items assess frequency or degree, typically over the past 4 weeks, using five response options (scored 1–5). Scores from each of the 45 questions are used to calculate five domains of health with higher scores indicating better health. The domains include Satisfaction (with health and self) with 9 items, Comfort (physical and emotional symptoms and limitations in activity) with 12 items, Resilience (behaviors that enhance health including family involvement) with 8 items, Risk Avoidance (of behaviors that pose risk to health) with 8 items and Achievement (developmentally appropriate role functioning in school and with peers) with 8 items. The domains are scored as item-level averages. Seventy percent of items need to be completed to be calculated otherwise the scale score is considered missing. The parent and child reports have been validated and shown to be predictors of children’s health care use and services.^{12,13,,20,21,25,26} They have been used to assess the health related quality of life of children with ADHD.^27,28 and to examine the relationship of social class gradients to health in childhood.²⁹

The Child Report form includes the 45 questions or items illustrated by a cartoon-type race-, age-, and gender– neutral character which anchors the ends of each set of 5 Likert-type graduated response circles, the smallest circle indicating the least amount or “never” and the largest circle most or “all the time²⁰ (Figure 1). The Child Report has good domain internal consistency reliability ranging from 0.70 to 0.82 and test-retest reliability ranging from 0.63 to 0.66.^20,30 The questionnaire was administered by research assistants unaware as to whether the child was ELBW or NBW and took up to 20 minutes to complete. The research assistant usually assisted the child in reading the questions and explained the response format. After looking at the illustrations the child marked an “X” in the circle corresponding to their rating.

Figure 1

Examples of the Child Health and Illness Profile–Child Report Form²⁰ Items.

The Parent report form has the same 45 items included in the child form. It also includes 12 subdomains (31 additional items) and a Disorders section with acute and chronic conditions and psychosocial problems. These results are not included in the present report. It takes about 20 minutes to complete. Domain reliability is high with internal consistency of 0.79 to 0.88 (Cronbach’s alpha coefficient) and retest reliability of 0.71 to 0.85.^21,19 The parent form was administered to primary caregivers of the children. Four caregivers (two ELBW and two NBW) responded to less than 70% of the items in a specific domain which was thus considered missing.

The study protocol was approved by the Institutional Review Board of University Hospitals of Cleveland, and informed consent obtained from parents.

Statistical Analysis

Univariate comparisons between the ELBW and NBW groups were made using the student t test for continuous variables and the chi squared test or Fisher’s exact test for discrete variables. Multiple linear regression analyses were used to compare the domain scores of the ELBW and NBW child and parent forms adjusting for socioeconomic status (SES), sex and race. Because the child’s cognitive function may affect understanding and responding to the CHIP-CE questionnaire, in separate analyses we examined the effect of child IQ on their self report. With the available sample size of 202 ELBW and 176 NBW children the study has 80% power to detect a mean difference of 0.29 standard deviations, using 2-sided tests at the 0.05 significance level. Agreement between the parent and child domain scores was examined via paired sample t tests and intraclass correlation coefficients (ICCs). In secondary analyses we compared the outcomes of the ELBW and NBW children who were free of neurosensory impairments.

As in our previous reports, the measure of SES was defined as the mean of the sample z-scores of maternal education and median family income according to the 2000 census tract of the family’s residence.¹⁵ These serve as a proxy for a range of family and environmental factors. Race/ethnicity was considered as a social construct and self-identified by parents from a list of racial/ethnic categories used for federal reporting

Results

Comparison of Demographic and Birth Data and 8 year Outcomes

The ELBW and NBW children did not differ significantly with regard to their mothers’ sociodemographic background (Table 1). The ELBW children were studied at a significantly younger postnatal age than the NBW controls (8.7 ± 0.7 vs 9.2 ± 0.8 years, p< 0.001) because the NBW children could only be recruited after the ELBW child had been enrolled. Twelve percent of the ELBW children had neurosensory impairments. They also had significantly higher rates of subnormal IQ and asthma requiring medication.^15,16

Table 1

MATERNAL DEMOGRAPHIC RISK FACTORS, PERINATAL DATA AND 8 YEAR OUTCOMES

Comparison of the Child Reported CHIP-CE domain mean scores between ELBW and NBW children

According to child self-report, ELBW children did not differ significantly from the NBW controls in any of the domains of health (Table 2). The results were similar after excluding the 25 neurosensory impaired ELBW children. In multivariable analyses higher SES was significantly associated with more Comfort [Beta (β) 0.15 (0.06,0.24)] and better Achievement [β 0.10 (0.02,0.19)]; black race with less Comfort [β −0.38 (−0.21,−0.54)] and Risk avoidance (β −0.26 (−0.10,−0.42)]; and male sex with less Risk avoidance [β −0.21 (−.07,−0.35)]. In separate analyses, higher child IQ (MPC > 84) was significantly associated with more Comfort [(β) 0.24(95% Confidence Interval (CI) 0.07,0.42)] and Risk avoidance [β 0.22 (0.06,0.39)]; In analyses that considered age of the child, age was not associated with any of the outcomes.

Table 2

COMPARISON OF CHILD AND PARENT REPORT DOMAIN SCALE SCORES BETWEEN EXTREMELY LOW BIRTH WEIGHT (ELBW) AND NORMAL BIRTH WEIGHT (NBW) CHILDREN^a

Comparison of the Parent Reported CHIP-CE domain and subdomain mean scores between ELBW and NBW Children

Parents of ELBW children compared to those of NBW children reported significantly less Satisfaction with health and Comfort for their children (Table 3). They also reported poorer Achievement and less Risk avoidance. Resilience did not differ between groups. The results were similar after excluding the neurosensory impaired ELBW children.

Table 3

COMPARISON OF PARENT AND CHILD DOMAIN SCORES IN ELBW AND NBW POPULATIONS

In the multivariable analyses, higher SES was significantly associated with better health in all the domains of health including Satisfaction [β 0.11(95% CI 0.05,0.18)], Comfort [ β 0.16 (0.10,0.22)], Resilience [ β 0.13 (0.07,0.18)], Risk Avoidance [β 0.18 (0.11,0.25)] and Achievement [β 0.24 (0.16,0.32)]. Male sex was associated with less risk avoidance [β −0.24 (−0.13, −0.35)], and black race with less Resilience [β −0.15 (−0.06,−0.26)] and Risk avoidance [β −0.14 (−0.02,−0.26)].

Agreement between Parent and Child Reports

The mean scores of parents of both the ELBW and NBW children were significantly different from those of their respective children for Comfort, Resilience and Achievement. The parent scores for Comfort and Resilience were higher (i.e. better) and the scores for Achievement, lower (i.e poorer) than the children’s scores. Among the ELBW population parents also reported lower scores (less satisfaction) than the children themselves. Reports of risk avoidance did not differ significantly between ELBW and NBW parents and their children. (Table 3). Intra class correlation coefficients were in general low, although slightly higher for risk avoidance. The findings were similar after excluding the neurosensory abnormal children. There were no gender differences in any of these analyses.

Discussion

We sought to examine the health status of 8 year old ELBW children from the perspective of the children and their parents. Our results reveal very little agreement between the self-reports of the children and the proxy reports of their parents with children reporting less comfort and resilience than their parents but better achievement. Despite higher rates of asthma and cognitive and neurosensory impairments, 8-year old ELBW children view their health and well being similar to that of NBW controls. Parents of the ELBW children reporting significantly poorer health for their children than parents of NBW children, specifically poorer satisfaction with health, comfort and achievement and less risk avoidance. The majority of findings were similar when ELBW children with neurosensory impairments were excluded.

This is the first report of the self assessed health and well-being of preterm children prior to adolescence. Previous information has relied on parents acting as proxies for their children with findings similar to our parent reports.^1–3 The self-reports of our ELBW children are in agreement with studies of adolescent preterm children which indicate very few difference between the children’s perceptions of their health and that of NBW term controls.^8–10

Our findings of poor agreement between parents and their 8 year old ELBW children concerning their health are similar to results obtained in the study of the original CHIP-CE normative sample of children where parent–child reports were poorly to modestly correlated.^20,21,30 Poor parent–child agreement has also been documented in other normative populations using a variety of questionnaires including the European KIDSSCREEN-52 questionnaire.³¹ Among British children the highest agreement between parents and children pertained to visible and diagnosed conditions and the lowest agreement to emotional symptoms such as sadness and anxiety.⁷ Stronger correlations between parent and child reports ranging from 0.44 to 0.61 were found among Dutch children.³²

Upton reviewed the 1996–2006 literature and concluded that parents of healthy children tended to report higher health related quality of life for their children than the children themselves whereas the assessments of parents of children with chronic illness were lower than those of their children.⁶ Our findings of poorer parent reported satisfaction with health and achievement for their ELBW children than the children themselves are in agreement with these findings. Ingerski also found that parents of children with chronic conditions reported poorer physical, emotional and social functioning but, in contrast to our findings, better school functioning than their children.³³ Achenbach reported low parent child correlations (0.22) for behavioral ratings with children reporting more internal and subjective symptoms and adults more objective behavioral symptoms.⁴ In contrast Saigal reported agreement between parents and their adolescent children with the only differences pertaining to sensation and cognition.³⁴

Many factors influence response to questionnaires. Parent reports may be influenced by their level of education and sociodemographic status as well as by their own health³⁵, their child care-giving burden and the child’s health status.^36–38 Children’s reports are influenced by their age, gender, health and cognitive level as well as their social experience.^39,40 Our study population was restricted to ELBW children capable of responding to the CHIP-CE questionnaire, thus excluding the severely impaired children. Parents may have reported even poorer satisfaction with health and achievement for their ELBW children had such children been included.

The predominant effect of SES on the health status of children has been well described.^29,41 We used a composite of maternal education and family income as a measure of SES and found a significant effect of SES on both parent and child reports of most of the health measures with higher SES associated with better health. Starfield similarly reported significant social class differences in parent reported domains of health, with the exception of Satisfaction, but contrary to our findings, the effects of SES were not significant according to the child report.²⁹ A significant effect of maternal education on the self reported health of European children has however been reported, supporting our findings of an effect of SES on child reported health status.⁴¹

We found a significant association of black race with less Comfort and Risk avoidance. Poorer health status has been reported among black low birth weight children.^38,42 Cultural differences in responding to questionnaires, rather than poverty, may play a role in our population as the racial differences were evident even after adjusting for SES in the multivariable analyses. Gender differences were also apparent in our population which might be related to gender differences in responding to questionnaires.

Limitations of the study include that he children were born in the early to mid 1990’s, a period of increased survival, but also of increased neonatal morbidity which has decreased since the year 2000.^43,44 The findings might thus not reflect current outcomes. Ours is a predominantly urban population and might not be representative ofother regions.

This is to our knowledge the first report of the school-age health of preterm children prior to adolescence who have survived since the 1990’s. Strengths of the study include our measure of health status, the CHIP-CE, which provides a comprehensive, multidimensional assessment of health. Although different, the perspectives of both the children and their parents present equally valid perceptions of the functioning and well being of the child with each providing complementary information. Parents and children may use different standards to appraise health and well being. Furthermore parents may not be aware of subjective symptoms among their children such as sadness, loneliness and anxiety.⁴⁵ This is evident in our population where the children reported less Comfort, which includes emotional comfort, and less Resilience, which includes family involvement, than their parents. The child’s perspective is thus important when making health decisions and to identify such aspects of their emotional and social lives that parents may not be aware of and that may possibly be improved with interventions. The parents’ perspective also has importance because parents control most aspects of the child’s life including their referral to and utilization of health care. Furthermore both parent and child reports of health and well being predict current and future health care needs and service use and are increasingly viewed as primary and secondary end points of health care.^25,26.

In conclusion, the findings of this study stress the importance of considering the self perception of the health status of preterm children when assisting them with any educational and social difficulties they may have. Longitudinal follow up of this cohort will be important in order to examine possible changes in parent and child perception of health which may become evident during adolescence.

Acknowledgments

This study was supported by grants R01 HD 39756, M01 RR000 and ULI RR024989 from the National Institute of Health (NIH).

Dr. Hack supervised the study and had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Drs. Hack, Taylor, Forrest and Drotar developed the study concept and design. Drs. Hack and Andreias acquired the data.

Drs. Hack, Schluchter, Taylor, Forrest, Drotar, Holmbeck and Andreias participated in the analysis, including statistical analysis and interpretation of the data.

Dr. Hack drafted the first version of the manuscript and all the co-authors participated in the critical revision of the manuscript and approve its submission for publication.

We thank Mrs. Miriam Curran, who coordinated the project and participated in the interview of the parents; Terry Reid, Jennifer Eppich, and Mary Morrow, all research assistants, who tested the children and administered the questionnaires to the children and their parents; Lydia Cartar who participated in the initial data management and analysis and Bonnie Tarantino and Alpher Torres who provided clerical assistance.

Footnotes

None of the authors have any conflicts of interest.

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