Sandra K. Mitchell

Home environment and cognitive development in the first 3 years of life: A collaborative study involving six sites and three ethnic groups in North America.

Attempted to examine the generalizability of environment/development relationships among 3 ethnic groups across the first 3 years of life. Social status did not show a consistent relationship to either quality of home environment or childrens developmental status across the various groups. Results indicated a fairly consistent relationship between HOME scores and childrens developmental status, although there were some ethnic and social status differences in the relationship. Measures of specific aspects of the childs home environment, such as parental responsivity and availability of stimulating play materials, were more strongly related to child developmental status than global measures of environmental quality such as SES. When the childs early developmental status and early home environment were both very low, the likelihood of poor developmental outcomes was markedly increased compared with cases when only one was low.

Interobserver Agreement, Reliability, and Generalizability of Data Collected in Observational Studies

Research in developmental and educational psychology has come to rely less on conventional psychometric tests and more on records of behavior made by human observers in natural and quasi-natural settings. Three coefficients that purport to reflect the quality of data collected in these observational studies are discussed: the interobserver agreement percentage, the reliability coefficient, and the generalizability coefficient. It is concluded that although high interobserver agreement is desirable in observational studies, high agreement alone is not sufficient to insure the quality of the data that are collected. Evidence of the reliability or generalizability of the data should also be reported. Further advantages of generalizability designs are discussed.

Predicting intellectual outcomes: Sex differences in response to early environmental stimulation

Sex differences in parent-child interaction and infant development patterns were examined in a longitudinal sample of 193 parent-infant pairs. Few differences were found. However, there were differences in the patterns of prediction of later intellectual and linguistic outcomes for boys and girls. Stronger predictions of IQ or language skill were obtained for boys from measures of the mothers developmental expectations, the extent of the fathers involvement in the infants early care, the provision of appropriate play materials, and the extent of parental life change. Stronger predictions were found for girls for a measure of restriction and punishment. The combination of these two groups of findings — lack of difference on measures of environment and parent-child interaction, and the presence of differences in prediction — suggest that the same experiences produce difference effects for boys and girls.

Developmental Generalizability of the HOME Inventory.

A generalizability study was conducted to examine the consistency and stability of scores on a measure of environmental stimulation over the first two years of life. Total scores on the HOME inventory were quite consistent over time, but subscales were less so. Examination of subscales by canonical correlation and principal components factor analysis indicated that the organization of the environment changes over the first two years of life, and it is the amount of stimulation, rather than the particular type of stimulation, which is relatively stable.

Prediction of School and Behavior Problems in Children Followed from Birth to Age Eight

For a number of years in the late 1960s and early 1970s there was astonishing agreement among those interested in child welfare that the best way to serve children’s interests was through the early detection of learning and behavior problems. This belief was due in part to the outcomes of two major longitudinal studies—the Kauai study (Werner, Bierman, & French, 1971; Werner & Smith, 1977) and the National Collaborative Perinatal Study (Broman, Nichols, & Kennedy, 1975). Both of these had demonstrated that perinatal status variables had significant, although modest, relationships with later cognitive and motor development (Smith, Flick, Ferris, & Sellman, 1972; Werner et al., 1971). Moreover, it appeared that the effects of these perinatal status variables were mediated by the quality of the environment in which the child was raised.

The generalizability study as a method of assessing intra- and interobserver reliability in observational research

Most researchers use interobserver agreement percentages to express the quality of their observational data. A better method is the generalizability study, which allows the variance in a set of scores to be partitioned among several sources, such as observers, occasions, subjects, and error. In this paper the practical application of generalizability theory is described and illustrated, using the frequency and duration of two behaviors observed during the mother-infant interaction. This method allows the user to assess intra- and interobserver differences and to examine the relationship between these differences and subject characteristics.