Early child care and mother–child interaction from 36 months through first grade

Infant Behavior & Development 26 (2003) 345–370

Early child care and mother–child interaction from 36 months through first grade NICHD Early Child Care Research Network∗ University of Texas, Dallas, P.O. Box 830688, Richardson, TX 75083-0688, USA Received 1 July 2002; received in revised form 24 October 2002; accepted 18 December 2002

Abstract Relations were examined between early non-maternal child care experience in the child’s first 3 years and mother–child interaction when children were 3, 4.5, and in first grade. Longitudinal analyses investigated relations between cumulative child care experiences across the first 3 years and mother–child interaction from age 3 through first grade to test whether results pertaining to 4.5-year-olds and first graders deviated from those found across the first 36 months in this sample of 1,180 from the NICHD Study of Early Child Care. Previously found relations in the first 3 years were restricted to certain subsamples at these later ages: More non-maternal child care experience across the first 3 years was associated with less maternal sensitivity and less positive engagement of mother for White children but greater maternal sensitivity and child positive engagement for non-White children through first grade. Positive associations of mother–child interaction with hours of child care were similar for both African-American and Hispanic children. Negative associations between hours of care and sensitivity diminished over time for all children. Higher quality early child care experience was related to greater maternal sensitivity through first grade primarily when children had experienced relatively few hours of care. Early experience with higher quality child care benefited children’s positive engagement with mother through first grade when their mothers were depressed. Results were similar whether effects were examined for non-maternal care or for non-parental care in which father care was excluded from considerations of child care experience. © 2003 Elsevier Science Inc. All rights reserved. Keywords: Child care; Mother–child interaction; NICHD Study of Early Child Care; Mother–child relationship

∗ Corresponding author. Present address: NICHD Early Child Care Research Network, NICHD, 6100 Executive Blvd., 4A01, Rockville, MD 20852, USA. E-mail address: [email protected] (NICHD Early Child Care Research Network).

0163-6383/$ – see front matter © 2003 Elsevier Science Inc. All rights reserved. doi:10.1016/S0163-6383(03)00035-3

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1. Introduction In the United States today, reliance on non-maternal child care beginning in the first year of life has become normative (Hofferth, Brayfield, Deich, & Holcomb, 1991; NICHD Early Child Care Research Network, 1997). More than half of all mothers of infants under a year of age and 63% of mothers with preschoolers under 3 years of age are in the labor force (U.S. Department of Labor, 1999). It is not surprising, in view of the importance attributed to mother’s care in cultural ideals and scientific theories (McCartney & Phillips, 1988), that such high rates of non-maternal care usage—beginning in infancy and continuing throughout the preschool years—have fostered disagreement about how such early experience may affect the developing mother–child relationship (e.g., Belsky, 1986, 2001; Clarke-Stewart, 1988). Two bodies of research have emerged addressing this issue, one focused upon the security of infant–mother attachment and the other upon patterns of mother–child interaction. This report focuses on patterns of mother–child interaction, not just because it addresses both the child’s and mother’s side of the relationship, but because mother–child interaction patterns prove to be significant predictors of a variety of developmental outcomes (e.g., Bornstein & Tamis-LeMonda, 1989; Pianta & Egeland, 1994; Rogoff, Mistry, Goncu, & Mosier, 1993). Using data from the NICHD Study of Early Child Care, a prospective, longitudinal investigation of approximately 1,300 children enrolled at birth, we examined associations between the amount, quality, and type of child care across the first 3 years and mother–child interaction when children were 3, 4.5 years old, and in first grade. This extends work presented in a previous report that examined relations between early child care and mother–child interaction during the first 3 years of life. Most research on child care and mother–child interaction has focused upon the amount of non-maternal care which children experience. This is because several developmentalists have theorized that time away from the child may undermine the mother’s capacity to get to know her child well and thus provide sensitive, responsive, and growth-facilitating care (Brazelton, 1986; Sroufe, 1988; Vaughn, Gove, & Egeland, 1980). As it turns out, a large number of investigations have not supported this hypothesis, failing to detect differences in mother–child interaction associated with the amount of child care (Burchinal, Bryant, Lee, & Ramey, 1992; Caldwell, Wright, Honig, & Tannenbaum, 1970; Cohen, 1978; Egeland & Heister, 1995; Goldberg & Easterbrooks, 1988; Gottfried, Gottfried, & Bathurst, 1988; Hock, 1980; Pedersen, Cain, Zaslow, & Anderson, 1982; Rabinovich, Suwalsky, & Pedersen, 1986; Schubert, Bradley-Johnson, & Nutall, 1980; Schwartz, 1983; Stith & Davis, 1984; Zaslow, Pedersen, Suwalsky, Cain, & Fivel, 1985). But this is by no means true of all the relevant research. Several investigations of mother–infant interaction found that, at least within the first 6 months of life, more time spent in non-maternal care (or more maternal employment) is related to less sensitive, supportive maternal behavior and/or less harmonious mother–child interaction (Campbell, Cohn, & Meyers, 1995; Clark, Hyde, Essex, & Klein, 1997; Owen & Cox, 1988; Stifter, Coulehan, & Fish, 1993). Belsky (1999) recently reported, as well, that more time in non-maternal care across the first 3 years of life predicted more negative mothering, though other studies of toddlers and preschoolers have found the opposite—use of child care being associated with more positive maternal behavior (Caruso, 1989; Crockenberg & Litman, 1991; Schwartz, 1983; Vandell, 1979).

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The most comprehensive investigation of the issue to date was carried out as part of the NICHD Study of Early Child Care (NICHD Early Child Care Research Network, 1999). Relations between non-maternal child care and ratings of maternal sensitivity and child positive engagement during mother–child interaction at 6, 15, 24, and 36 months were examined for 1,274 mothers and their children. In longitudinal analyses that controlled for maternal and family predictors of mother–child interaction associated with both the amount and quality of child care used and additional child and family qualities associated with mother–child interaction, child care proved to be a modest but nevertheless significant predictor of maternal sensitivity and child engagement. With respect to amount of time in child care, more hours of child care predicted less maternal sensitivity and less positive child engagement across all ages of measurement. The primary purpose of the current report is to extend this research in order to determine whether these child care effects are evident beyond the preschool years. Thus, we ask whether effects of early child care on mother–child interaction discerned up through age 3 are maintained, amplified, or attenuated as children experience the transition to school. Despite widespread appreciation of the importance of high-quality child care for promoting child well being, the relation between this dimension of child care experience and mother–child interaction has rarely been a focus of inquiry. Nevertheless, prevailing views regarding the consequences of higher and lower quality child care on both children and parents lead to the expectation that more sensitive, supportive mothering and more positive child responsiveness should be associated with higher quality of child care experience. More specifically, especially as children develop and become increasingly active contributors to the mother–child dyad, better quality early child care experience could enhance patterns of mother–child interaction via its effect on children’s developing competencies (NICHD Early Child Care Research Network, 1999, 2002) and perhaps via contributions to children’s expectations of responsive care from adults. Consistent with this view are Peterson and Peterson’s (1986) data showing that preschoolers in poor-quality center care engaged in fewer verbal interchanges with their mothers than children in either high-quality center care or in the full-time care of their mothers. Experience with low-quality child care could undermine positive interactions between mother and child if those experiences contributed to less compliant or more difficult or problematic child behavior that could strain the mother–child relationship. Benefits of higher quality child care for mother–child interaction may also ensue when caregivers offer particularly good models of sensitive and supportive nurturance of the children in their care. Relevant, perhaps, are Marshall’s (1991) data showing that low-income parents whose children were in high-quality child care centers reported consistently high levels of pleasure in watching their children grow, whereas those in lower quality centers and those not using child care showed declines in parenting pleasure. Support for the hypothesis that quality of child care matters for mother–child interaction was found in our earlier examination of mother–child interaction across the child’s first 3 years (NICHD Early Child Care Research Network, 1999). With controls for family income and two-parent status, maternal education, depressive symptoms, and separation anxiety, and child gender and temperament, higher quality child care predicted greater maternal sensitivity across the children’s first 3 years of life, but was unrelated to the children’s positive engagement of their mothers in observed interactions. Again the question posed in the current investigation is

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whether such apparent effects of early child care quality on mother–child interaction endure or dissipate over time as children develop. We include the degree of instability in early child care in characterizing experiences of child care across the first 3 years. Although we did not find instability of child care to be related to mother–child interactions in children’s first 3 years in our earlier report, and Goldberg and Easterbrooks (1988) similarly found no effects, longer term benefits or risks of child care experiences may relate to the stability of the early child care arrangements. Examination of main effects of child care might mask important differences in associations with child care for different subgroups of children. Early child care could have positive effects on family processes in some families and negative effects in others (e.g., Bronfenbrenner & Crouter, 1982; Desai, Chase-Lansdale, & Michael, 1989; Hoffman, 1989). For example, child care may offer respite and buffer stress for the mother–child relationship when mothers are parenting under conditions of adversity (Harwood, 1988), when mothers are psychologically stressed, or families are otherwise at risk. Indeed, Cohn, Campbell, and Ross (1991) found that infants of depressed mothers who used more hours of child care were more often securely attached to their mothers than were infants of depressed mothers who used fewer hours of child care. For low-income families, the increased family income that accompanies maternal employment may have positive effects on family functioning (McLoyd, 1993). However, early child care may constitute an added risk to the mother–child relationship among stressed or at-risk families (see, e.g., Belsky et al., 1996). The quality of the child care experience may moderate such associations. Low family income, maternal depressive symptoms, and child race/ethnicity were examined as potential moderators of the effects of early child care in the first 3 years on mother–child interaction through the transition to school. Although there was no clear evidence in our earlier report through age 3 for differential effects of child care by maternal depression, low income, or child ethnicity, the present study examined whether these indicators of family risk moderate the longitudinal effects of early child care experiences in the first 3 years on mother–child interaction across the transition to school. In summary, to examine the relation between early child care experiences of young children and the mother–child relationship, data from the NICHD Study of Early Child Care were used to address three related questions: (1) Do children’s child care histories with respect to amount, quality, and stability of child care in the first 3 years predict qualities of mother–child interaction from age 3 through first grade? (2) Are associations between cumulative early child care experience ages 0–3 and mother–child interaction through first grade similar across this period that crosses the transition to school, or do they change over time? (3) Are associations between early child care and mother–child interaction across the transition to school moderated by maternal depressive symptoms, low family income, and child ethnicity?

2. Method 2.1. Participants Participants in the NICHD Study of Early Child Care were recruited throughout 1991 from hospitals located in or near Little Rock, AR; Irvine, CA; Lawrence and Topeka, KS; Boston,

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MA; Philadelphia, PA; Pittsburgh, PA; Charlottesville, VA; Morganton and Hickory, NC; Seattle, WA; and Madison, WI. During selected 24-hour sampling periods, 8,986 women giving birth were visited in the hospital to determine their eligibility for the study. Subjects were excluded from the sample if (a) the mother was under 18; (b) the mother did not speak English; (c) the family planned to move; (d) the infant was not a singleton; (e) the infant was hospitalized for more than 7 days following birth or had obvious disabilities; (f) the family lived too far away or in a very unsafe neighborhood; or (g) the mother had a known or acknowledged substance-abuse problem. Of those visited in the hospital in the initial sampling periods, 5,265 met the eligibility criteria for the study and agreed they could be contacted after their return home from the hospital. Randomized call lists were generated by a central data center. Families were called in order from the list to enroll two to three families into the study per week at each site. Final recruitment occurred at the first home visit when the infants were 1 month old. One thousand three hundred and sixty-four families were enrolled in the study. The recruited families included 24% ethnic-minority children (including 13% African-American, 6% Hispanic, and 5% other), 11% mothers without a high school education, and 14% single-parent mothers. (Note that these percentages are not mutually exclusive.) The recruited families did not differ significantly from other families eligible to participate in terms of major demographic variables, except that the mothers in the study had a 4% higher rate of intention to be employed compared with the non-participating mothers. Actual rates for mothers’ employment plans for their infants’ first year reflected 53% full time, 23% part time, and 24% no employment. The sample was not designed to be nationally representative. However, we compared the demographic characteristics of the sample with those of people living in the same census tracts and with national statistics. The sample was similar to families in the same census tracts and to the nation as a whole on demographic variables of household income and ethnicity. For families included in the present analyses, mean years of mothers’ education was 14.43 years (SD = 2.46). Average income-to-needs ratio was 3.47 (SD = 2.47) when the child was 3 years old and 3.72 (SD = 2.50) when the child was in first grade. The vast majority of families had a male partner living in the home (84% when the child was 3 and 81% when the child was in first grade); at first grade 78% of the child were White/non-Hispanic and 22% were non-White (11% African-American, 6% Hispanic, and 5% other). Number of hours per week in child care across the child’s first 3 years ranged from 0 to more than 50. Among families whose child was in child care for at least 10 hours per week (74% of the study participants in the infant’s first year), amount of child care averaged 24 hours per week from 0 to 6 months, 34 hours from 7 to 15 months, 34 hours from 16 to 24 months, and 33 hours from 25 to 36 months. Mother–child interaction data at 36 months, 54 months, and in first grade were available for 1,148, 1,027, and 992 families, respectively. Compared with families with at least one observation of mother–child interaction at these ages, those not observed had lower maternal education, income, and higher maternal separation anxiety and depressive symptoms; they were also more likely to be without partners (26% vs. 12%) and non-White (35% vs. 22%). The families who were not included in the present study analyses did not differ from those included in terms of maternal sensitivity at 6 months, child temperament at 6 months, or child gender. We also examined attrition following the 36-month assessments. The 135 families with 36-month mother–child interaction data but not 54-month data differed from the other families

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in terms of lower education (M = 13.4 vs. M = 14.3), less maternal sensitivity (M = 16.2 vs. M = 17.1, p < .05), and less positive child engagement of mother (M = −0.33 vs. M = 0.04, in standardized scores; p < .05). However, the families lost to follow-up did not differ with respect to income, maternal depression at 36 months, or child care hours from 0 to 36 months. Except as noted, all comparisons were significant at p < .01. The noted differential attrition may indicate a somewhat more restricted range of families over time. Children who spent 10 or more hours per week in non-maternal care at major data collection periods were observed in child care at those ages to assess child care quality. Of those eligible to be observed, 78.6% were observed at 6 months, 77.4% at 15 months, 85.8% at 24 months, and 90.3% at 36 months. Eligible children were not observed due to caregiver refusal, child absence from child care, and recent changes in the child care setting. Compared with those who were eligible but not observed in child care, families in the observed sample had higher incomes, the mothers had higher education, and the children experienced more hours of care and were more likely to be in less formal child care.

3. Overview of data collection Visits to the families took place when the children were 1, 6, 15, 24, 36, and 54 months, and when they were first graders. Observations of mother–child interaction were conducted at lab visits when children were 36 and 54 months old and in first grade. Observations in non-maternal child care arrangements were conducted when the children were 6, 15, 24, and 36 months old. Telephone interviews to update maternal employment and child care information were conducted at 3-month intervals between 3 and 36 months. At home and lab visits, mothers were interviewed regarding household composition, family income, and significant life events. In addition, mothers completed a number of questionnaires, including assessments of child temperament, maternal depression and separation anxiety. 3.1. Measures 3.1.1. Mother–child interaction measures Mother–child interaction was videotaped in semi-structured 15-minute observations at each age. In the observation task at 36 months mothers were asked to show their children age-appropriate toys in three containers in a set order. A set of washable markers, stencils, and paper was in the first container, a set of dress-up clothes and a cash register in the second, and a set of Duplo blocks with a picture of a model in the third container. The mother was instructed to have her child play with the toys in each of the three containers and to do so in the order specified. At 54 months and in first grade, interaction activities included two tasks that were too difficult for the child to carry out independently and required the parent’s instruction and assistance. In addition, a third activity was included that encouraged play between mother and child. In the 54-month visit, the first activity was completing a maze using an Etch-A-Sketch that had been altered by attaching a maze to the screen. The second activity was to form a series of same-sized rectangular cube “towers” from variously shaped wooden blocks. The third activity was play with a set of six hand puppets, consisting of two parrots, two frogs,

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and two blue alligators. For first graders, the first mother–child interaction activity involved mother and child operating an Etch-A-Sketch together to draw a specified picture of a house and tree on the screen. The task was challenging because one was to control the vertical knob and the other the horizontal knob and thereby coordinate how they worked together to draw, which was especially difficult when drawing diagonal lines. The second activity involved the child using different shaped parquet pattern blocks (Learning Resources #LER 634) to fill in three geometric cutout frames (Addison-Wesley/Cuisenaire #034796). The third activity was a card game invented for the procedure called “one-up/one-down,” a modification of “slap-Jack,” whereby the mother and child were to successively lay cards face up on a growing pile between them and race to slap and claim the pile of cards when the card laid on the pile is either one higher or one lower than the previous card. This activity was included to provide an opportunity to observe expressions of affect from mother and child and the child’s emotional regulation with mother in a potentially exciting and/or frustrating activity. Data were collected across the 10 sites by research assistants who attended a common training meeting prior to the visits. To ensure standard data collection procedures across the sites, each data collector first passed certification procedures based on a central certifier’s review and approval of videotaped administrations of the procedures. The videotapes of mother–child interaction were shipped to a central, non-data collection location for coding. Coders were blind to other information about the families. Teams of five or six coders scored the videotapes from each time period, with some overlapping membership in the teams across the different ages (i.e., one coder served on all three of the teams, two served on two of the teams). Coders received intensive training and supervision and met periodically to recode tapes together as a group throughout the period of formal scoring. Mother–child interaction was rated using 7-point global rating scales modified from Egeland and Heister (1995) to apply to the interaction activities at each age. The maternal rating scales included mothers’ supportive presence, respect for the child’s autonomy, stimulation of cognitive development, quality of assistance, and hostility. These rating scales were designed to capture the mother’s emotional and instrumental support for the child’s engagement with the task activities and collaborative interactions between mother and child. Child behavior rating scales included enthusiasm/agency in the tasks, negativity (expressed toward the mother), persistence (orientation to the tasks in the session), affection for mother (at 36 months and first grade; positive orientation to mother and sharing of positive affect), positive experience of the session (at 54 months; child’s positive feelings of doing well and having a good relationship with parent), and affective mutuality (reciprocated, shared feelings support mutuality in the dyad). Coders rated both maternal and child behavior from a single viewing of the videotaped interactions. The ratings of maternal and child behavior thus reflect qualities of the dyad’s relationship as exhibited in the observed interaction. To parsimoniously describe the quality of mother–child relations in interaction, a priori composites of maternal sensitivity and child engagement of mother were formed from the individual ratings. The maternal sensitivity composite represented affectively positive, non-intrusive, respectful, responsive and supportive maternal care. It was formed at each age from the sum of the ratings for supportive presence, hostility (reverse scored), and respect for autonomy. Cronbach’s alphas for the maternal sensitivity composites were 0.78 at 36 months, 0.84 at 54 months, and 0.82 at first grade.

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The child positive engagement composite at 36 months was the sum of child affection to mother and negativity (reverse scored). At 54 months it was the sum of experience of the session, felt security, and negativity (reverse scored). The child positive engagement composite from first grade ratings was the sum of affection to mother, felt security, and negativity (reverse scored). Internal consistency, as determined by Cronbach’s alpha, for the engagement composites at 36 months, 54 months, and first grade were 0.78, 0.82, and 0.80, respectively. Inter-coder reliability was determined by assigning two coders to 19–20% of the tapes randomly drawn at each assessment period. Coders were unaware of which tapes among their assignments were assigned to second coders, and reliability assessments were made throughout the period of coding. Inter-coder reliability was calculated as the intra-class correlation (Winer, 1971). Reliability for the maternal sensitivity composites was 0.84, 0.88, and 0.91 at 36 months, 54 months, and first grade, respectively. Reliability for the child composites were 0.77, 0.82, and 0.80. 3.1.2. Stability of dependent variables over time Correlations between maternal sensitivity composites at different ages were moderately strong and ranged from .49 to .52, which were somewhat higher correlations than found among sensitivity ratings across the child’s first 3 years (NICHD Early Child Care Research Network, 1999). The correlations over time for the child positive engagement composites ranged from .22 (between 36 months and first grade) to .32 (between 54 months and first grade). Correlations of child engagement composites over time in the first 3 years ranged from .15 to .27. All reported stability correlations are highly significant (p < .001). Correlations between maternal sensitivity and child engagement were moderately strong at each age (r’s ranged from .60 at 36 months to .62 in first grade). Despite the strength of these relations between maternal and child behavior, we examined maternal and child behavior in separate analyses of the effects of child care to allow us to focus on both the mother’s and child’s behavior in interaction with each other. The dyadic context of the mother’s and the child’s behaviors are clearly recognized. This followed the approach used in the previous report relating child care experiences to mother–child interaction in the first 3 years. 3.1.3. Child care variables At 3-month intervals, starting when the infants were 0–1 month old, mothers were telephoned and asked about their current child care arrangements, from which information was gathered about amount and stability of care. Child care was defined as care provided to the child on a regular basis each week by someone other than the child’s mother. Thus, child care was defined as regular child care provided in the mother’s absence and thereby considered the care provided by fathers (when on a regular basis in the mother’s absence), grandparents and other relatives inside or outside of the child’s home, non-relatives in the child’s home, non-relatives outside the child’s home, family child care, and center-based care. We recognize that parents of young children often chose to limit arrangements for the care of their children to close family members, and will choose care by fathers, when mothers’ and fathers’ work schedules will allow, or grandparents or other close relatives over care outside of family relations. In studying the effects of child care experience, the grouping of all non-maternal care

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arrangements, without further distinction between father care and other non-parental care, can raise objections. The approach of the NICHD Study of Early Child Care has been to examine effects of non-maternal care, as defined above, although characteristics of both non-maternal and non-parental care have been described in some reports (see NICHD ECCRN, 1997). Although the substantive findings in the present report pertain to the study of early non-maternal care experiences, results of follow-up analyses excluding father care from the measures of child care are also provided. Description of the child care measures below pertain to non-maternal care. The amount of child care across the child’s first 3 years was measured by the mean hours of non-maternal child care per week during each month from 0 to 36 months gathered from maternal report. Instability of child care in the first 3 years was indexed by the mother’s report of the number of non-maternal care arrangements that were started from 0 to 36 months. Quality of child care experienced over the child’s first 3 years was assessed from observations of non-maternal child care at 6, 15, 24, and 36 months for children spending at least 10 hours per week in a regular non-maternal care arrangement. Observations of the sensitivity, involvement, and stimulation provided by caregivers in non-maternal care settings were conducted on two half-days that were scheduled within a 2-week interval. During these sessions, observers scored characteristics of caregiving as experienced by the study child using the Observational Record of the Caregiving Environment (ORCE; see NICHD Early Child Care Research Network, 2000). The ORCE focuses on the quality of caregiving for the target child. ORCE data collection comprised four 44-minute cycles over 2 days. Each 44-minute cycle consisted of four 10-minute observation periods, plus two 2-minute periods between the second and third 10-minute period for observation notes pertaining to qualitative ratings. Observers recorded the occurrence of specific caregiver behaviors directed to the child for each minute during the first three 10-minute cycles for frequency scores of caregiving characteristics. The fourth 10-minute period was devoted to observations pertinent to qualitative ratings. Quality of care was indexed by a composite denoting positive caregiving based on the sum of five of the 4-point qualitative ratings: Sensitivity to non-distress signals, Stimulation of cognitive development, Positive regard expressed to the child, Detachment (reverse scored), and Flatness of affect (reverse scored), with Fostering exploration and Intrusiveness (reverse scored) added to the 36-month composite. The quality of care index at each age was formed from an average of this composite over the four cycles of observation from the 2 days. Cronbach’s alphas for the quality composites were 0.89, 0.88, 0.86, and 0.82 at 6, 15, 24, and 36 months, respectively. The quality composites had very good inter-observer reliability with “gold standard” videotapes (0.94, 0.86, 0.81, and 0.80) and with live reliability partners at all ages (0.90, 0.89, 0.89, and 0.90). In analyses for this paper, quality of child care was the mean quality of child care from 6 to 36 months from these ORCE quality composite ratings. 3.1.3.1. Covariates. Results of child care studies are often difficult to interpret because they fail to take into account covariation between child care parameters and family factors related to the selection and use of child care. Covariates included in the present paper were the same set used in the earlier of report of relations between child care experience and mother–child interaction in the child’s first 3 years (see NICHD ECCRN, 1999, for more details of covariate inclusion criteria). Covariates included were site of data collection, family income, maternal

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education, marital/partnered status of the mother, maternal depressive symptoms, maternal separation anxiety, child gender, difficult temperament, and ethnicity. Income-to-needs ratio was computed from maternal reports of total family income collected at the home visits. Total family income including government payments was divided by the appropriate poverty threshold for each household size for that year according to U.S. Census Bureau tables. Concurrent income-to-needs at 36 and 54 months and in first grade were included in the analyses as a time-varying covariate. Maternal education was the mother’s years of education as reported when the infant was 1 month. Mother’s marital/partnered status (either married or living with a domestic partner vs. all others) was determined from interviews at each age. Marital/partnered status was included in the analyses as a time-varying covariate of mother–child interaction outcomes. Maternal depressive symptoms were measured using the Center for Epidemiological Studies Depression Scale (CES-D, Radloff, 1977) administered at each home visit. Cronbach’s alphas for the CES-D ranged from 0.90 to 0.91. The depression scores had moderately strong correlations over time (.46 to .51). Maternal separation anxiety was assessed at 1, 6, 15, and 24 months using the 21 items of Subscale I of the Separation Anxiety Scale (Hock, Gnezda, & McBride, 1983). (Separation anxiety was not measured after the 24-month assessment.) High scores indicate high levels of maternal worry, sadness, and guilt during separation from her child, and adherence to beliefs about the value of exclusive maternal care. Internal consistency exceeded 0.90 for each assessment. A measure of infant temperament was based on 55 6-point items from the Infant Temperament Questionnaire (Medoff-Cooper, Carey, & McDevitt, 1993) completed by mothers at

Table 1 Means (standard deviations) or frequencies for variables included in the analyses Dependent variables

36 months

54 months

Grade 1

n Maternal sensitivity Child engagement

1148 17.19 (2.78) 11.13 (2.00)

1027 16.94 (2.91) 16.36 (3.05)

992 16.88 (3.02) 16.47 (2.96)

Covariates Income/needs Maternal education Child gender (male) (%) Difficult temperament Ethnicity White (%) African-American (%) Hispanic (%) Other (%) Partner in household Depressive symptoms Separation anxiety 0–36 months child care Hours Quality Instability

3.47 (2.47) 14.46 (2.45) 51 3.18 (.41) 78 11 6 4 84 9.18 (8.31) 69.87 (13.24)

3.46 (2.36) 14.41 (2.47) 50 3.18 (.41) 78 12 6 4 83 9.73 (8.63) 69.74 (13.17)

3.72 (2.50) 14.42 (2.46) 50 3.17 (.41) 78 11 6 4 81 8.37 (8.46) 69.23 (13.11)

21.55 (15.11) 2.88 (.44) n = 872 3.12 (2.60)

21.68 (15.05) 2.89 (.43) n = 783 3.11 (2.57)

21.87 (15.00) 2.88 (.43) n = 765 3.16 (2.64)

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the 6-month home visit. A composite representing difficult temperament was formed from the mean of items from the Approach, Activity, Intensity, Mood, and Adaptability subscales (with appropriate items reflected). Higher scores represented more difficult temperament (e.g., “My baby is fussy or cries during the physical examination by the doctor.”). Cronbach’s alpha was 0.81. The child’s ethnicity was categorized as White/non-Hispanic or non-White in initial analyses of child ethnicity because sizes of the different non-White groups were relatively small. The non-White group was diverse and included African-American, Hispanic, Asian, and Native American children. When significant interactions between child ethnicity and child care features suggested a need for further study, follow-up analyses were conducted by subdividing child ethnicity as White/non-Hispanic, African-American, Hispanic, and other children. Means and standard deviations (or descriptive percentages) for all measures included in the analyses are presented in Table 1.

4. Results 4.1. Data analysis plan Relations between features of child care in the first 3 years and mother–child interaction at 36 and 54 months and in first grade, controlling for child and family variables, were analyzed using a repeated measures general linear mixed model analysis (Jenrich & Schluchter, 1986; Laird & Ware, 1982). We tested the extent to which mother and child interaction qualities varied as a function of selected demographic, child, family, and early child care factors and whether those patterns of association changed over time (36 months, 54 months, and first grade). Separate intercepts were estimated for each individual, with the assumption that across-time assessments are correlated. Separate variances and correlations for each repeated assessment were estimated. The model included both time-varying predictors (income, depressive symptoms, marital/partner presence in household) and between-subject predictors (site, maternal education, child gender, child temperament, child ethnicity, maternal separation anxiety, early child care hours, early child care quality, and early child care instability). Covariates in the model are similar to those tested in the earlier report of mother–child interaction in the first 3 years with the exception of the addition of child ethnicity. Interactions among certain variables were tested by adding them simultaneously to the model: quality × hours of child care, maternal depressive symptoms × each child care variable, income × each child care variable, and child ethnicity × each child care variable. All main effects were evaluated at the mean of all other variables, so a significant main effect for a variable involved in a significant interaction meant that the variable was significant at the average level of the other variable. Results are presented for maternal sensitivity (Table 2) and for child positive engagement of mother (Table 4) separately. Two samples were tested, the whole sample (n = 1,180), which includes children with no early child care experience, and the subsample (895 of 1,180) of children who were observed in child care in their first 3 years. Results are reported in detail only from the analyses of the subsample observed in early child care in order to save space and because the complete set of child care parameters of the amount,

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Table 2 Results of the repeated measures regression model predicting maternal sensitivity (sample observed in early child care (n = 895)) Fmain a

Ftime

β

β36

β54

βG1

ns ns ns ns ns

−0.02 (0.03) 0.00 (0.02) 0.08 (0.02)∗∗

−0.06 0.004 0.09

0.02 −0.005 0.06

0.03 0.014 0.09

0.16 0.03

0.12 −0.00

0.15 0.03

−0.10 0.09

−0.06 0.13

−0.01 0.18

0.19 0.13

0.22 0.06

0.27 0.07

∗∗∗

Site Child care block CC hours CC #arrangements CC quality Quality × hoursb Quality @ low hours Quality @ high hours Ethnicity (White) × hours Hours @ White Hours @ non-White

3.62 (9, 875) 5.52 (5, 875)∗∗∗ ns ns 10.8 (1, 875)∗∗ 6.99 (1, 875)∗∗

Demographics block Mat education Income

56.1 (2, 875)∗∗∗ ns 65.3 (1, 875)∗∗∗ ns 10.1 (1, 875)∗∗ ns

Child block Gender Temperament Child ethnicity (White)

23.9 (3, 875)∗∗∗ ns ns 69.6 (1, 875)∗∗∗

4.28 (6, 875)∗∗∗ 8.62 (2, 875)∗∗∗ 0.00 (0.05) −0.14 a ns −0.01 (0.02) −0.01 4.34 (2, 875)∗ 0.54 (0.06)∗∗∗ 0.41

Family block Mat depression Partner in home Separation anxiety

ns ns ns ns

2.54 (6, 875)∗ 5.87 (2, 875)∗∗ ns ns

9.11 (1, 875)∗∗

ns

0.14 (0.04)∗∗∗ 0.02 (0.03) −0.06 (0.03) 0.13 (0.06)∗ 0.23 (0.03)∗∗∗ 0.08 (0.03)∗∗

−0.03 (0.02) 0.07 (0.05) −0.01 (0.03)

0.01 c 0.14 b 0.00 −0.01 0.53 0.68

−0.10 a∗ −0.01 b 0.13 0.06 −0.03 −0.01

0.03 b 0.00 0.00

Note: (a, b) Coefficients with different letters reflect significant changes over time in the association between that predictor and maternal sensitivity; comparisons were tested only when interaction with time was significant. a F for the effect of the predictor × time. b Maternal depressive symptoms × child care variables, income × child care variables, and child ethnicity (White vs. non-White) × child care variables were added to the model simultaneously, only significant interactions are listed. ∗ p < .05. ∗∗ p < .01. ∗∗∗ p < .001.

quality, and stability of care could only be examined for the sample observed in child care, where ratings of child care quality were made. Findings with respect to associations with amount of care in the whole sample analyses (the only child care parameter examined in the whole sample analyses) are described to provide comparison and elaboration to findings with respect to the amount of early child care reported from the child care sample analyses. Associations between mother–child interaction and the family and child covariates were very similar across the sets of analyses and thus are reported only for the child care sample analyses. In the tables presenting these results, the statistical tests and estimates of effects are organized by blocks pertaining to the demographic, child, and family covariates and the child care variables. The child care block is presented at the top of the tables. Tests at the block level tested the joint contribution of all the variables in that block with all other variables in the model controlled in this simultaneous regression. These results are presented in bold in the tables. At

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the level of individual parameters, coefficients for a given variable are presented over time and for each age predicted. F and p values are reported for tests of main effects of each predictor and of interactions of the predictors with time (e.g., time × maternal depression). In the case of a significant interaction with time, the results of pairwise contrasts between parameters at the different ages are indicated in the table and described below. When interactions with time were not significant, tests of significance for the parameter at each age are not indicated. For interactions between hours and quality of care, and between depression and child care, income and child care, and child ethnicity and child care variables, only significant interactions are shown in the tables. Significant parameter coefficients are presented in bold. Tables report the coefficients when all variables in the analyses are standardized to have mean = 0 and standard deviation = 1 across time. Thus, coefficients can be interpreted in terms of the relative magnitude they reflect in predicting the mother–child interaction dependent measures in the presence of the other predictors in the model. The predictor and outcome measures were standardized with a mean of 0 and standard deviation of 1 because the outcome measures were collected at the interval, not ratio level, and thus, the metric of measurement is not inherently meaningful across time. For this type of measure, relative position of each dyad at each point in time in relation to the sample provides the most interpretable level of measurement, comparable to repeated measures analyses of standardized measures that are often performed of cognitive skills (Campbell & Ramey, 1994) and social skills (Kupersmidt, Burchinal, & Patterson, 1995). 4.2. Child care and maternal sensitivity Results involving analyses from the general linear mixed model of maternal sensitivity are reported in Table 2. The results shown in the table are those for the sample observed in child care in the child’s first 3 years. 4.2.1. Amount of early child care Although hours of early child care in the first 3 years, as a main effect, did not predict maternal sensitivity (after controlling for other predictors) in the sample observed in child care, a significant interaction between hours and ethnicity was found in the prediction of maternal sensitivity (which was not further qualified by time). Regression coefficients indicated a significantly positive effect of hours of care on maternal sensitivity through first grade for non-White children, but no significant association of sensitivity with hours for the White sample. Thus, for the non-White sample, more time in child care in the first 3 years significantly predicted greater maternal sensitivity through first grade. In the analysis of the whole sample, a significant main effect of hours of early child care was found (F(1, 1, 163) = 3.91, p < .05) as well as an interaction between hours of care and child ethnicity (F(1, 1, 163) = 6.71, p < .01), though inspection of regression coefficients revealed a somewhat contrasting pattern of results relative to the sample observed in child care. In the case of the whole sample, more time in non-maternal care predicted less maternal sensitivity for the whole sample (β = −0.04 (SE = 0.02), p < .05), but more hours in early child care was related to less maternal sensitivity only for White children (β = −0.07 (SE = 0.02), p < .01) and not for non-White children (β = 0.05 (SE = 0.04), ns).

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Table 3 Predicted adjusteda values of maternal sensitivity illustrating significant interactions in the regression models Maternal sensitivity

Hours × ethnicityc Ethnicity White African-American Hispanic Other Quality × hoursd Quality Low qualitye High qualitye

Whole sample hours

Sample observed in child care hours

Lowb

Highb

Low

High

0.17 −0.64 −0.24 −0.41

0.05 −0.53 −0.07 −0.37

0.17 −0.68 −0.32 −0.58

0.06 −0.45 −0.02 −0.37

−0.09 −0.03

0.11 −0.00

a

Values adjusted for all other predictors in models. Low hours = 7.6; high hours = 35.6. c Predicted values from follow-up model with four-way classification of ethnicity. d Predicted values from original model with two-way classification of child ethnicity. e Low quality = 2.58, high quality = 3.1. b

In order to follow-up the significant interactions between hours of care and child ethnicity and examine patterns of associations between hours of early child care and sensitivity for African-American and Hispanic children, the two largest non-White groups in the sample, we reran the models classifying child ethnicity as White, African-American, Hispanic, and other. The interaction between child ethnicity and hours of child care was again significant in the analyses of the sample observed in early child care (F(1, 871) = 2.92, p < .05) but non-significant in the whole sample. To further illustrate these predictions of maternal sensitivity from hours of care by child ethnicity from the child care sample and whole sample analyses, Table 3 provides predicted values for sensitivity, adjusted for all other predictors in the model, for White children and for African-American, Hispanic, and other non-White children who experienced low amounts of child care (defined as the 25th percentile value in our sample distribution; 7.6 hours) and who experienced high hours of care (defined as the 75th percentile value; 35.6 hours). Across the whole sample and the child care sample analyses, the predicted values illustrate that high hours of early child care was related to lower maternal sensitivity for the White sample but related to higher maternal sensitivity for the non-White groups. Note that the predicted values illustrate a similar pattern of positive associations with hours of care for both the African-American and the Hispanic children. In addition, the whole sample analysis of maternal sensitivity contained evidence for a significant interaction of hours of early child care with time (F(2, 1, 163) = 3.10, p < .05). Tests of the significance of the hours coefficients at each age indicated that in the whole sample more hours of child care in the first 3 years was related to lower maternal sensitivity at age 3 (β = −0.09, p < .0) but not at subsequent ages (β = −0.02, ns, at both ages). The three-way interaction of hours × ethnicity × time was not significant, in either the child care sample

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or the whole sample analyses, indicating that the difference between White and non-White children in associations between hours of early care and sensitivity did not differ over time. The two-way interaction between hours and time reflects that associations between hours and sensitivity became less negative over time across the entire sample. 4.2.2. Quality of child care As shown in Table 2, early child care quality was significantly associated with maternal sensitivity, with higher quality child care experience in the first 3 years related to greater maternal sensitivity at 36 months and subsequently through first grade. This main effect of quality, however, was qualified by a significant interaction between quality and quantity of care. Higher quality early child care was significantly associated with greater maternal sensitivity at low hours of care but not at high hours of care. Predicted values for sensitivity for these groups, adjusted for other predictors in the model, are shown in Table 3 for children who experienced low hours of early child care (predicted from the 25th percentile score of 7.6 hours) in high-quality (75th percentile score of 3.1) and low-quality (25th percentile score of 2.58) child care and children who experienced high hours of early child care (75th percentile score of 35.6 hours) under conditions of high-quality care and low-quality care. The predicted values illustrate that mothers were more sensitive across observations at 36 and 54 months, and in first grade when their children experienced higher quality care and relatively few hours of child care across the first 3 years.1 4.2.3. Associations of sensitivity with family and child factors Predictions of maternal sensitivity from the family and child covariates in the models are shown in Table 2. Greater sensitivity was related to more maternal education, higher income-to-needs, and White ethnicity. Interactions of the predictors with time indicated significantly less sensitivity with sons than daughters at 36 months but greater sensitivity with sons than daughters in first grade. A significant depression × time interaction indicated that maternal depressive symptoms were significantly associated with significantly less sensitivity at 3 years, but less strongly related at subsequent ages. 4.3. Child care and child positive engagement of mother Results of the analyses of child engagement of mother are displayed in Table 4. There were no main effects of hours, quality, or stability of child care in the first 3 years on child engagement of mother. Significant interactions of hours × child ethnicity and quality × maternal depression indicated conditions under which the amount and quality of early child care were related to child engagement of mother in mother–child interaction. To interpret the significant ethnicity × hours interactions for child engagement, regression coefficients for hours for White children and hours for non-White children were examined, as shown in Table 4. More early child care hours predicted less child engagement of mother through first grade for White children but more positive child engagement through first grade for non-White children. A somewhat similar hours by child ethnicity interaction was found in analyses of the whole sample (F = (1, 1, 164) = 5.18, p < .05), with evidence that hours of early child care was negatively related to child engagement of mother for White children

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Table 4 Results of the repeated measures regression model predicting child engagement Fmain a 2.53 (9, 876)∗∗

Child care block CC hours #Arrangements CC quality White ethnicity × hoursb Hours @ White ethnicity Hours @ non-White ethnicity Quality × M depression Quality @ low depression Quality @ high depression

3.64 (5, 876)∗∗ ns ns ns 7.46 (1, 876)∗∗ 5.45 (1, 876)∗

β

β36

β54

βG1

ns ns ns ns ns

−0.02 (0.03) 0.03 (0.02) 0.04 (0.02)∗∗

−0.06 0.01 0.06

0.02 −0.00 0.01

0.00 0.07 0.06

−0.06 (0.03)∗∗∗ 0.12 (0.06)

−0.09 0.09

−0.06 0.12

−0.04 0.14

0.00 (0.03) 0.07 (0.03)∗

0.03 0.09

−0.03 0.03

0.02 0.08

0.09 (0.03)∗∗ 0.07 (0.03)∗

0.04 0.11

0.10 0.06

0.14 0.03

ns

Demographics block Mat education Income

12.9 (2, 876)∗∗∗ 10.2 (1, 876)∗∗ 5.48 (1, 876)∗

ns ns

Child Gender (male) Temperament Child ethnicity (White)

6.48 (3, 876)∗∗∗ ns ns 18.7 (1, 876)∗∗∗

2.25 (6, 876)∗ 6.49 (2, 876)∗∗∗ ns ns

0.01 (0.05) −0.01 (0.03) 0.29 (0.07)∗∗∗

−0.17 a 0.00 0.27

0.10 b −0.02 0.32

0.09 b −0.01 0.29

Family Maternal depression Partner in home Separation anxiety

3.09 (3, 876)∗ 5.06 (1, 876)∗ ns ns

ns 3.05 (2, 876)∗∗ ns ns

−0.05 (0.02)∗ 0.03 (0.05) −0.05 (0.03)

−0.11 a 0.10 −0.06

−0.06 −0.02 −0.01

0.01 b 0.02 −0.07

Note: (a, b) Coefficients with different letters reflect significant changes over time in the association between that predictor and child engagement of mother; comparisons were tested only when the interaction with time was significant. a F for interaction of predictor × time. b Maternal depressive symptoms × child care variables, income × child care variables, and child ethnicity (White) × child care variables were added to the model simultaneously; only significant interactions were listed. ∗ p < .05. ∗∗ p < .01. ∗∗∗ p < .001.

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Site

Ftime

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Table 5 Predicted adjusteda values of child positive engagement of mother illustrating significant interactions in the regression models Ethnicity Child engagement Whole sample Hours × ethnicity White African-American Hispanic Other

Sample observed in child care

Lowb

Highb

Low

High

0.11 −0.28 −0.25 −0.19

−0.01 −0.23 −0.02 −0.16

0.11 −0.44 −0.34 −0.19

−0.01 −0.20 −0.01 −0.17

c

Quality × maternal depressiond Depressive symptoms Low qualitye Low depressionf High depressionf

0.02 −0.085

High qualitye 0.26 0.009

a

Values adjusted for all other predictors in models. Low hours = 7.6, high hours = 35.6. c Predicted values from follow-up model with four-way classification of child ethnicity. d Predicted values from original model with two-way classification of child ethnicity. e Low quality = 2.58, high quality = 3. f Low depression = 3, high depression = 13. b

(β = −0.06 (SE = 0.02), p < .05), but unrelated to child engagement for non-White children (β = 0.05 (SE = 0.04), ns) in the whole sample. In follow-up analyses of the hours × child ethnicity interaction, we reran the models of child engagement classifying child ethnicity as White, African-American, Hispanic, and other. The interaction between child ethnicity and hours of child care in the prediction of child engagement was again significant in the analyses of the sample observed in early child care (F(1, 872) = 2.83, p < .01) but non-significant in the whole sample. Predicted values for child engagement are shown in Table 5 to further illustrate the interactions of hours and ethnicity. For the White sample, predicted values from low hours of care (at the 25th percentile value) and from high hours of care (at the 75th percentile value) indicate more positive engagement of mother when children experienced few hours of early child care. For the African-American and Hispanic groups, predicted means from low hours of care compared with high hours of care indicate children were more positively engaged with their mothers when they experienced more hours of early child care. The meaning of the significant quality × depression interaction from the child care sample analyses is suggested by the significant regression coefficient for the prediction of child engagement from quality of child care for mothers with high depressive symptoms and the non-significant coefficient for the prediction from quality for mothers with low depressive symptoms (see Table 4). Table 5 displays predicted adjusted values to further illustrate this interaction. As shown by the predicted adjusted values for child engagement from high-quality child care (75th percentile value) and low-quality care (25th percentile value) under conditions of low depression (predicted from the 25th percentile value of three symptoms) and high depression (predicted from the 75th percentile value of 13 symptoms), the benefit of high-quality early child care for child engagement was seen far more for children of mothers

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with relatively high numbers of depressive symptoms than for children of mothers with few depressive symptoms. Moreover, the more positive engagement of their mothers by children of depressed mothers when the children had experienced high-quality early child care indicates some buffering of maternal depression on children’s engagement of mother. The predicted values also indicate that experience of low-quality early child care adds risk for the child’s engagement with mother when mothers have high depressive symptoms. Significant predictors of child positive engagement of mother from among the covariates in the model (see Table 4) indicated that children were more positively engaged with their mothers when family income-to-needs ratios and maternal education were higher, children were female (but only for interactions at age 3), children were White rather than non-White, and mothers had fewer depressive symptoms. Predictions from maternal depressive symptoms differed over time; more depressive symptoms were related to less positive child engagement of mother only at age 3. 4.4. Follow-up analyses omitting father care from child care experience A final set of follow-up analyses were examined to ask whether the associations between early non-maternal child care experience and mother–child interaction through first grade would differ if non-parental care were the focus of interest. We omitted hours of care by father and recalculated hours of child care to represent hours of care by someone other than the child’s mother or father; measures of child care quality were based on observations of non-parental child care experience. This recalculation reduced the sample observed in child care from 895 to 810. When the models were retested with father care excluded, the pattern of significant findings remained the same, with significant interactions between hours of care and child ethnicity, between quality and hours of care, and between quality of care and maternal depression (predicting child engagement). Results of these analyses are available upon request.

5. Discussion Very few studies have examined qualities of mother–child interaction longitudinally over several years’ time spanning from preschool into the school-aged years (Weinfield, Ogawa, & Egeland, 2002). In the NICHD Study of Early Child Care we have followed a large sample of children and their families from birth through middle childhood with repeated measurement of qualities of mother–child interaction beginning at age 6 months. Prior to the present inquiry, questions of the relation between early child care experience or maternal employment and mother–child interaction at different ages have relied primarily upon cross-sectional evidence, with only a few exceptions (see Gottfried, Gottfried, & Bathurst, 1995). The present study allowed longitudinal examination of these questions. We extended the investigation presented in a previous report from the NICHD Study of Early Child Care (NICHD ECCRN, 1999) which examined relations between child care and mother–child interaction across the child’s first 3 years with an examination of relations between cumulative early child care experience in the first 3 years and mother–child interaction when the earlier studied children were 3 and 4.5 years of age and in first grade. Although

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mother–child interactions extended through age 3 in the previous report, we included this age in the present study in order to explicitly test for differences at these later ages with the associations previously reported. Evidence for the previously found relations between more hours of child care and lower quality mother–child relations and between higher quality child care and greater maternal sensitivity was found in this longitudinal follow-up, but was restricted to certain subsamples and conditions. The presence of several significant interactions qualified any main effects of quantity or quality of early child care on mother–child interaction through first grade and indicated several differences at these later ages from findings reported for mother–child interaction in the first 36 months of life. In this follow-up through first grade, more hours of child care in the first 3 years were related to less maternal sensitivity and child positive engagement for White children but were related to greater maternal sensitivity and more positive child engagement of mother for non-White children. These differences between White and non-White children in the relations between amount of care and quality of mother–child interaction were evident across the age 3 through first-grade observations. However, the interaction between hours of early child care and time in predicting maternal sensitivity in the whole sample indicated that in general negative associations between the amount of early child care and maternal sensitivity diminished over time, with associations becoming less negative over time for White children and more positive for non-White children. It should be noted that relations between mother–child interaction and hours of care for White and non-White dyads were not consistently significant across the whole sample and the child care sample analyses. One association was consistently significant across analyses of both samples—the relation between more child care experience in the first 3 years and less positive engagement of mother through first grade for the White children. The negative association with maternal sensitivity found for White children was significant only in the whole sample analyses. The relations between more hours of early child care and more positive mother–child interaction found for non-White children, for both maternal sensitivity and positive child engagement, were significant only in the child care sample analyses. One difference in the parameters of child care examined in the two sets of analyses—the inclusion of child care quality among the parameters in the child care sample analyses—may account in part for differences in the significance of associations with hours across samples. In addition, children who did not experience early child care or who were not observed in child care could only be included in the whole sample analyses. Positive relations found in the earlier report between the quality of early child care experience and mother–child interaction across the first 3 years extended through first grade under certain conditions. Higher quality early child care was related to greater maternal sensitivity through first grade but only when children had experienced relatively few hours of early child care. In addition, experience with higher quality child care was associated with the child’s more positive engagement of mother in mother–child interaction when mothers were depressed. The different associations of child care with mother–child interactions for White and nonWhite children provide support for the contention that maternal employment and the use of child care may have different effects on family processes depending on family circumstances, parenting and employment attitudes and commitments, and cultural beliefs (e.g., Bronfenbrenner & Crouter, 1982; Hoffman, 1989; Lamb, Owen, & Chase-Lansdale, 1980). The finding that

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more experience in early child care would relate to higher quality mother–child interactions for non-White children, with similar patterns found for both African-American and Hispanic children, was not specifically predicted, either on the basis of previous findings from the NICHD Study of Early Child Care or the research literature pertaining to child care and the mother–child relationship. It should be noted that there was a trend for child ethnicity to moderate the association between hours and maternal sensitivity in these children’s first 3 years; this early trend gains meaning in the present follow-up analyses. The present child care findings for non-White children, apparent for both African-American and Hispanic children, gain some support from one small-sample investigation of 45 children. In this study low-income predominantly African-American mothers of children receiving full-time child care of varied but mostly good to high quality became more involved with their infants over time, while mothers providing exclusive care of their children did not (Burchinal et al., 1992). The different associations with hours of care by child ethnicity in the present study cannot be ascribed to associated differences in family income, given the inclusion of the income-to-needs ratio among the family characteristics controlled in the analyses. Continued investigation of these processes clearly requires additional study. Among the family and child predictors in the models, child ethnicity was a notably strong predictor of differences in mother–child interaction. Were differences in mother–child interaction associated with child race/ethnicity due in part to rating biases? Measures of maternal responsiveness, harshness, and intrusiveness derived from the observational ratings of mother–child interaction were found to be comparable across the African-American and European American families when the children were 36 months using multiple-group mean and covariance structures analysis (Whiteside-Mansell, Bradley, Owen, Randolph, & Cauce, 2000). Associations between maternal responsiveness and child prosocial behavior and behavior problems were similar across the groups, but racial group differences were found in associations between harsh and intrusive parenting and child problem behaviors at this age (Whiteside-Mansell et al., in press). The cultural equivalence of the observational measures of mother–child interaction should receive continued investigation, and studies of cultural equivalence of the measures should be extended to the later ages examined in the present study. How might we understand the finding that high-quality early child care experience was associated with greater maternal sensitivity through first grade primarily when few hours of care were used in the early years? Understanding relations between child care quality and mother–child interactions involve consideration of the nature of the interface between the child’s child care and family environments. Our speculations engage Bronfenbrenner’s (1979, 1986) notion of mesosystem influences, or the interconnections between settings which the child experiences. According to Bronfenbrenner’s ecological theory, each setting’s developmental potential is enhanced when linkages between settings are strong. Closer partnerships between child care providers and parents that involve sharing information about the child have been found to relate to more positive caregiving of both mothers and their child care providers (Owen, Ware, & Barfoot, 2000), suggesting a mechanism by which higher quality child care may be associated with higher quality mother–child interactions. Two-way communication between caregivers and parents and sharing of information tend to go along with high-quality child care (Ghazvini & Readdick, 1994). In addition, when the quality of child care is high, caregivers are potentially good models of positive caregiving. But why were positive relations

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between mother–child interaction and child care quality found primarily when early child care was used for few hours per week? It may be that the opportunity to experience support from good child care providers and to observe good quality caregiving is greater when mothers are less pressed by long hours of work demands. Parents spend relatively little time dropping off and picking up their children from child care. Interactions with caregivers tend to be infrequent and brief (Ghazvini & Readdick, 1994; Zigler & Turner, 1982). Shpancer (in press) reports that most mothers and especially mothers working full time do no talk much with their care providers. Our findings may reflect these pressures. Other explanations for relations found between the quality of early child care and maternal sensitivity are also possible. The experience of high-quality child care may teach the child valuable relationship skills by providing experiences with responsive and supportive caregivers and increased maternal sensitivity with higher quality child care may reflect such child effects. The findings also reflect that the experience of poor-quality child care with unresponsive, unsupportive caregivers may undermine the child’s relationship skills and interactions with mother. In addition, the findings suggest that children’s relationships with their mothers do not benefit from early high-quality child care if experienced on a full-time basis. The issue is clearly complicated and calls for further study of the dynamics of relations between mother–child interactions and child care environments. Maternal depression moderated the relation between early child care quality and children’s positive responsive engagement of their mothers. The evidence suggested a buffering effect of child care quality for children’s engagement with mother when the mother had elevated symptoms of depression. Quality of child care was unrelated to child engagement when mothers were not depressed but was associated with higher engagement of mother at relatively high levels of maternal depressive symptoms. Adjusting for all other predictors in the analysis model, children of depressed mothers with experience in high-quality early child care had engagement scores similar to the children of non-depressed mothers, while children with depressed mothers who experienced low-quality child care had the lowest predicted scores, indicating that low-quality early child care was an added risk to these children’s relationships with their mothers. Experience with responsive, stimulating child care providers in high-quality child care across the first 3 years of life appeared to benefit these children’s relationships with their mothers through first grade, as evidenced by more positive engagement of mother in mother–child interactions relative to children with depressed mothers who had experienced lower quality care in early child care. Similar to the earlier seeds of the present findings related to child ethnicity from analyses of child care relations with mother–child interaction in the first 3 years, the previous study’s analyses examining maternal depression as a moderator of the associations with child care found a modest trend suggesting that more hours in higher quality care was related to more child engagement for children of depressed mothers at 24 and 36 months. We see from the present findings the value of longitudinal follow-up of the effects of early child care experience into the children’s school-aged years. Several limitations and qualifications to the study should be noted. Mother–child interaction was measured in relatively brief samples of semi-structured situations. In comparison, the measures of child care quality were much more extensive, with four observations made over 2 days. It should be noted that the study’s assessments of mother–child interaction have been

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reliable predictors of the children’s social and cognitive behavior (NICHD Early Child Care Research Network, 2001), but more extensive and naturalistic measurement might produce different conclusions regarding early child care and mother–child interaction (Crockenberg & Litman, 1991). The higher attrition of low-income and minority participants over time limit generalizations that can be drawn, however the proportion of non-White children (22%) was steady over this phase of the study, from the child’s third year through first grade. Restrictions in the sample to families who resided neighborhoods considered safe for assistants making home visits, according to police reports, indicate some further limitations to generalizations that can be drawn from the present findings. Concerns have been raised that the study may be somewhat limited in its ability to examine effects of low-quality child care. Recent reports of associations between extremely low-quality center care and insecure infant–mother attachments among Israeli children indicate that different findings regarding child care quality may emerge when low-quality care is more prevalent (Sagi et al., 2002). In the NICHD Study, permissions to observe child care settings were more often denied, particularly in the first 15 months, when less formal forms of child care were used and when caregivers were less educated. As the proportion of children receiving center-based child care increased with age, a greater proportion of permissions to observe were obtained (NICHD ECCRN, 2000). Moreover, proportions of poor, fair, good, and excellent care observed in the NICHD Study were similar to reports from large-scale national studies in the U.S. in the preschool years (NICHD ECCRN, 2000), indicating that the variability in quality of care studied in the present study appears similar to variations in care quality generally examined in the U.S. In sum, findings relating early child care experience to mother–child interaction in the first 3 years of life were extended in the present study to examine associations of the early child care experience to mother–child interactions through the children’s transition to school, but results deviated from those reported in the earlier years. The previously found relations between more hours of child care and lower quality mother–child relations in the first 3 years and between higher quality child care and greater maternal sensitivity were restricted to certain subsamples at these later ages, and a buffering effect of higher quality care was found for effects of maternal depression on children’s positive engagement of mother. These results are the first to highlight differences in relations of child care with mother–child interaction by child ethnicity, and for this reason merit replication and require further study to discern why these processes appear to operate differently for White and non-White children and their mothers. Further study of the various conditions under which child care experiences relate to children’s development and family processes would appear warranted. Note 1. Additional analyses were carried out to determine whether the greater effect of quality of care when children experienced low hours of care was an artifact of experience in center care (where children were more likely to experience more hours of child care) or experience in relative care (where children may have experienced fewer hours of care). No support for this possibility was found. Further details are available upon request from the authors.

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Acknowledgments This study is directed by a Steering Committee and supported by National Institute of Child Health and Human Development (NICHD) through a cooperative agreement (U10) that calls for scientific collaboration between the grantees and the NICHD staff. The participating investigators are listed in alphabetical order: Virginia Allhusen (University of California, Irvine), Jay Belsky (Birkbeck University of London), Cathryn Booth (University of Washington), Robert Bradley (University of Virginia), Celia A. Brownell (University of Pittsburgh), Margaret Burchinal (University of North Carolina, Chapel Hill), Susan B. Campbell (University of Pittsburgh), Alison Clarke-Stewart (University of California, Irvine), Martha Cox (University of North Carolina, Chapel Hill), Sarah L. Friedman (NICHD); Kathryn Hirsh-Pasek (Temple University), Aletha Huston (University of Texas-Austin), Elizabeth Jaeger (St. Joseph’s University), Jean Kelly (University of Washington), Bonnie Knoke (Research Triangle Institute), Nancy Marshall (Wellesley College), Kathleen McCartney (Harvard University), Marion O’Brien (University of North Carolina, Greensboro), Margaret Tresch Owen (University of Texas-Dallas), Deborah Phillips (Georgetown University), Robert Pianta (University of Virginia), Wendy Wagner Robeson (Wellesley College), Susan Spieker (University of Washington), Deborah Lowe Vandell (University of Wisconsin-Madison), and Marsha Weinraub (Temple University). We wish to express our appreciation to the study coordinators at each site who supervised the data collection, to the research assistants who collected the data, and especially to the families and child care providers who welcomed us into their homes and workplaces and cooperated so generously.

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