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Complex models for covariance matrices are structures that specify many parameters, whereas simple models require only a few. When a set of models of differing complexity is evaluated by means of some goodness of fit indices, structures with many parameters are more likely to be selected when the number of observations is large, regardless of other utility considerations. This is known as the sample size problem in model selection decisions. This article argues that this influence of sample size is not necessarily undesirable. The rationale behind this point of view is described in terms of the relationships among the population covariance matrix and 2 model-based estimates of it. The implications of these relationships for practical use are discussed.

The TPB-BrF is a comprehensive, theoretically based, empirically verified model that can serve as a useful heuristic for understanding the personal motivational components of breast-feeding behavior.

Models were interpreted in light of the TPB, previous findings, the social context for breastfeeding in Hong Kong, and statistical model-building. Cross-cultural measurement issues and the need for prospective designs are continuing challenges in breastfeeding research.

Youth living in impoverished urban neighborhoods are at risk for becoming hopeless about their future and engaging in violent behaviors. The current study seeks to examine the longitudinal relationship between social connections, hopelessness trajectories, and subsequent violent behavior across adolescence. Our sample included 723 (49% female) African American youth living in impoverished urban neighborhoods who participated in the Mobile Youth Survey from 1998 through 2006. Using general growth mixture modeling, we found two hopelessness trajectory classes for both boys and girls during middle adolescence: a consistently low hopelessness class and an increasingly hopeless class with quadratic change. In all classes, youth who reported stronger early adolescent connections to their mothers were less hopeless at age 13. The probability of later adolescent violence with a weapon was higher for boys and was associated with the increasingly hopeless class for both boys and girls. Implications for new avenues of research and design of hope-based prevention interventions will be discussed.

OBJECTIVE -To define incidence and predictors of nontraumatic lower-extremity amputation (LEA) in a diverse cohort of American Indians with diabetes. RESEARCH DESIGN AND METHODS -The Strong HeartStudy is a study of cardiovascular disease and its risk factors in 13 American-Indian communities. Data on the presence/ absence of amputations were collected at each of three serial examinations (1989 -1992, 1993-1995, and 1997-1999) by direct examination of the lower extremity. The logistic regression model was used to quantify the relationship between risk of LEA and potential risk factors, including diabetes duration, HbA 1c , peripheral arterial disease, and renal function.RESULTS -Of the 1,974 individuals with diabetes and without prevalent LEA at baseline, 87 (4.4%) experienced an LEA during 8 years of follow-up, and a total of 157 anatomical sites were amputated among these individuals. Amputation of toes was most common, followed by belowthe-knee and above-the-knee amputations. Age-adjusted odds of LEA were higher among individuals with unfavorable combinations of risk factors, such as albuminuria and elevated HbA 1c . Multivariable modeling indicated that male sex, renal dysfunction, high ankle-brachial index, longer duration of diabetes, less than a high school education, increasing systolic blood pressure, and HbA 1c predicted LEA risk.CONCLUSIONS -The 8-year cumulative incidence of LEA in American Indians with diabetes is 4.4%, with marked differences in risk by sex, educational attainment, renal function, and glycemic control. Diabetes Care 27:1885-1891, 2004D ata from the baseline examination of the Strong Heart Study (SHS) show that lower-extremity amputation (LEA) due to diabetes was present in 3% of the cohort and 6.3% of individuals with diabetes (1), findings that are generally consistent with previous studies (2-4) in other American-Indian tribes.Rates of incident LEA have been reported for several American-Indian tribes (5-8). Previous studies have shown that hyperglycemia (5,6,9,10), duration of diabetes (5,6), male sex (2,5,6,10), and prevalent microvascular disease (5,6,10) contribute to LEA risk in American Indians.The purpose of this study is to define the incidence of first LEA due to diabetes in a diverse, population-based cohort of American Indians with diabetes. We hypothesized that among SHS participants with diabetes, increasing age, diabetes duration, glycemic control, smoking, peripheral arterial disease, renal dysfunction, and male sex would predict incident LEA and that combinations of risk factors, such as poor glycemic control and renal dysfunction, would interact to increase LEA risk. RESEARCH DESIGN AND METHODS -The SHS was initiated in 1988 to investigate cardiovascular disease and its risk factors in American Indians (11). The design, methods, and laboratory techniques of the SHS have been previously reported (12,13). The SHS cohort consists of 4,549 participants aged 45-74 years from 13 AmericanIndian communities in Oklahoma, the Dakotas, and Arizona who were seen at the basel...

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