How much observational data is enough? An empirical test using marital interaction coding.

Using three different samples of couples (clinic, nondistressed community, and engaged), we found that 15 minutes was sufficient to witness enough behavior to make reliable (i.e., internally consistent) estimations of most Rapid Marital Interaction Coding System (Heyman & Vivian, 1993) code frequencies. Ten minutes is sufficient for many codes of interest. The ease in which "how much time is necessary" calculations can be made should entice behavioral investigators from a variety of content areas to publish such figures. By empirically investigating a factor that in most fields becomes reified through convention, investigators can conduct observational research that is both maximally efficient and maximally scientifically defensible.

Attachment security in infancy and early adulthood: a twenty-year longitudinal study.

Sixty White middle-class infants were seen in the Ainsworth Strange Situation at 12 months of age; 50 of these participants (21 males, 29 females) were recontacted 20 years later and interviewed by using the Berkeley Adult Attachment Interview (AAI). The interviewers were blind to the participants' Strange Situation classifications. Overall, 72% of the infants received the same secure versus insecure attachment classification in early adulthood, K = .44, p < .001. As predicted by attachment theory, negative life events-defined as (1) loss of a parent, (2) parental divorce, (3) life-threatening illness of parent or child (e.g., diabetes, cancer, heart attack), (4) parental psychiatric disorder, and (5) physical or sexual abuse by a family member-were an important factor in change. Forty-four percent (8 of 18) of the infants whose mothers reported negative life events changed attachment classifications from infancy to early adulthood. Only 22% (7 of 32) of the infants whose mothers reported no such events changed classification, p < .05. These results support Bowlby's hypothesis that individual differences in attachment security can be stable across significant portions of the lifespan and yet remain open to revision in light of experience. The task now is to use a variety of research designs, measurement strategies, and study intervals to clarify the mechanisms underlying stability and change.

Specificity of dating aggression and its justification among high-risk adolescents.

Ninety-five high-risk adolescents were studied to determine whether their dating aggression and its justification as a response to interpersonal problems were specific to the current partner, general to dating relationships, or part of a global age-mate (same-sex peers and opposite-sex dating partners) aggression problem. Approximately one-third of males and two-thirds of females reported physical aggression against their current dating partner. Males' aggression (and its justification) toward their current dating partner was part of a generalized pattern of dating aggression, whereas for females, physical aggression against a current dating partner (and its justification) was partner-specific and unrelated to aggression in other relationships. Findings are discussed with regard to intervention and future research on adolescent dating aggression.

Discriminant validity of the adult attachment interview.

The Adult Attachment Interview is a semi-structured interview developed to investigate adults' attachment representations. Subjects are asked to describe their parents as caregivers, explain these descriptions, describe how their parents typically responded to distress, and discuss their current relationships with their parents. They are also asked to describe any significant losses and/or instances of abuse during childhood. Scoring focuses on the accessibility of early experiences to memory and the coherence and plausibility of the subject's narrative. Discriminant validity is always an important issue with such measures because IQ and other cognitively loaded variables offer plausible alternative interpretations or represent important correlates that should be treated as covariates when the measure is used. In addition, complex, multifaceted interviews always pose the risk of assessing general social adjustment rather than a more narrowly defined construct. This study examines the discriminant validity of the AAI vis(-)à-vis intelligence, social desirability, discourse style, and general social adjustment in a sample of 53 native-English-speaking, married women with preschool children. They were assessed with the AAI, a written IQ test, the Social Adjustment Scale, the Employment Experience Interview (discourse style), and a measure of social desirability. There were modest but significant correlations with IQ scores and social adjustment. There was no relation between AAI classifications and discourse style or social desirability. These results substantially strengthen the case for interpreting the AAI as an attachment-related measure.