The life course perspective examines and analyzes changes from birth until death to increase our understanding of what gives shape to lives and health outcomes. But more importantly, it provides us with theory-informed anchors for building potentially effective public and community health programs. For example, the US Department of Health and Human Services, Health Resources and Services Administration, and Maternal and Child Health Bureau have selected the life course model as an organizing framework for addressing their public health mission of improving and protecting the health of the population, eliminating health disparities, and promoting health equity across population groups.1

The Center for Disease Control and Prevention, US Department of Health and Human Services, also ascribes to the life course health development framework as a tool for reorienting public health work,2,3 providing an exciting and innovative way to look at health and disease patterns. This model offers health care providers a transformative way to assess and intervene in some of our devastating health problems across populations and over time. The model combines social determinants and health equity with biology and the environment, which are critical in allowing health care providers to better identify patterns of health and disease.

Silverstein4 suggests that there are 2 distinct but interrelated life course perspective orientations: one has a demographic-structural perspective that focuses on cohort flow and social change, whereas the other focuses on life course as a socially constructed institution that guides sequencing and timing of life transitions across the age continuum-both orientations have been illustrated in this issue. First, Berndt and Williams provide examples of analytic approaches appropriate for addressing the complexity of interacting factors (infant and mother) leading to children's cognitive outcomes, and their premises logically fit with a demographic-structural perspective. In addition, the presentation of Lesser and Koniak-Griffin of a series of community-based participatory studies focusing on discovery of maternal and paternal strengths, evidenced by adolescents experiencing multiple contextual adversities, falls under the focus on sequencing and timing of life transitions. Their reported series of studies address health disparities facing Latino teens, with a focus on teen parents and HIV prevention. Lesser and Koniak-Griffin collected data that represented a variety of viewpoints and multifactorial influences that, although clearly indicative of health disparities experienced by this group, did not causally lead to poor parenting. Rather, the parenting life transition opened the door to the adolescent parents' personal growth and life-changing decisions.

Both articles illustrate a dialectical interaction between people and environment, with the article of Lesser and Koniak-Griffin revealing that individuals are not passive beings and that personal strengths can emerge and operate in the most difficult situations. The analyses of Berndt and Williams illustrate that, although significant, only 20% of the variance in poor cognitive outcomes of infants could be explained by risk factors, thus leaving open the potential for undisclosed positive factors to mediate and/or moderate the outcome.

Also in this issue, Zhao and colleagues used secondary data analysis to explore the complex phenomenon of obesity in children. Using the life course model, Zhao and colleagues measured a complex number of variables specifically related to parental perception of weight and support of physical activity. Although the variables studied provide important information, Zhao and colleagues recognize that future research needs to explore other factors suggested by the life course model.

In addition, Tapp and colleagues not only administered a variety of research techniques related to participatory research but also added geospatial analysis to help explain health disparities experienced by an uninsured Hispanic population. By using the life course model, Tapp and colleagues emphasize that a number of complex variables should be considered to evaluate primary care delivery systems for an uninsured Hispanic immigrant population.

Furthermore, Sampson and colleagues used the life course model to focus on the impact of stressors experienced by low-income caregivers of children with asthma. Qualitative research looked at the complex influence of many variables delineated in the model. Puglisi and colleagues also observed the complexity of obesity and used the model to help explain variables beyond an imbalance of food intake and exercise. In identifying the multiple variables contributing to obesity, Puglisi and colleagues used phenomenology to identify many of the environmental influences on this phenomenon.

Finally, Branscum and colleagues used the life course model as an overall perspective to guide the use of comic books in changing lifestyle behaviors. This was an innovative and creative way to target a large number of children who represent different socioeconomic levels. The results from this study demonstrate how complex this phenomenon is and, when using a 1-time media intervention such as the use of comic books, other factors may need to be considered. The life course model offers a variety of approaches to strengthen this creative intervention and researchers' thinking of using comic books or other media. For example, future research might consider refining the variable of "timing" to test the effectiveness of the media intervention by offering the intervention at age-appropriate transition points.

The complexity of life course perspective constructs offers challenges to the researcher who values the multiple effects of variables required to identify significant patterns related to health and disease. The studies presented in this special issue help describe the complexity of the life course model, with researchers using innovative research methods to evaluate complex constructs presented by the model. With this understanding, our contributors give useful information on some of the processes that influence some of our difficult health care problems.

-Michele C. Clark, PhD, RN

Issue Editor

School of Nursing

University of Nevada

Las Vegas

-Carrie Jo Braden, PhD, RN, FAAN

Issue Editor

Office of Nursing Research & Scholarship

School of Nursing

University of Texas Health Science Center at San Antonio

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