Social support increases in the year after inpatient treatment of depression.

High levels of social support are reported to protect against major depressive episode (MDE), but little is known about how social support changes during MDE. In this study, we measured total social support and four subtypes of social support in 75 psychiatric inpatients at the time of admission and one year later. The four subtypes of social support were tangible support, affectionate support, positive social interaction, and emotional/informational support. The majority of the sample were women (81%) with a mean age of 53.7+/-14.9 years. The severity of depressive symptoms improved over the year and was accompanied by a significant increase in two types of social support -- positive social interaction, and emotional/informational support. There was no significant change in tangible support or affectionate support. Linear regression showed that changes in all four subtypes were correlated with changes in depressive severity after adjustment for age, gender, and baseline clinical characteristics. While Instrumental Activities of Daily Living (IADL) scores also improved throughout the period of observation, and while the change in IADL scores were significantly associated with changes in social support, change in IADL scores were no longer significantly associated with change in social support after adjustment for change in depression severity. These results suggest that supportive relationships improve after psychiatric hospitalization for MDE, and these changes are best explained by reduction in depression severity.

Electroconvulsive therapy is associated with superior symptomatic and functional change in depressed patients after psychiatric hospitalization.

BACKGROUND: Major depressive episode is associated with quality of life (QOL) deficits, and QOL improves following remission of depression. We conducted an observational study of the relationship between depressive symptoms and QOL for 1 year after psychiatric hospitalization, and compared QOL in patients who received ECT against those who did not. METHODS: We examined 88 patients with major depressive disorder (53.4+/-15.4 years old; 69 women) upon admission, with repeated measurements at discharge, 1, 3, 6, and 12 months after discharge. Depression severity was measured with the Beck Depression Inventory. QOL measurements encompassed ADLs, IADLs, performance in major roles, and satisfaction with relationships. Treatment for depression was at the discretion of the respective physicians. RESULTS: Depression severity dropped dramatically by discharge, and changed little thereafter. QOL measures showed improvement at the first month, with additional improvement at the third month. Improvement in QOL was closely tied to improvement in depression severity. ECT during the index hospitalization was associated with greater improvement in depressive symptoms and in most measures of QOL. LIMITATIONS: The results of this study may not apply to the treatment of outpatients, and the large number of statistical comparisons may have resulted in some spurious associations. CONCLUSIONS: Inpatient treatment of depression is followed by improvement in QOL. Novel findings in this study include evidence that maximum improvement in QOL does not occur until an average of 3 months after discharge, and that ECT-treated patients had superior outcomes.

Latent class marginal regression models for modelling youthful drug involvement and its suspected influences.

In longitudinal behavioural studies, it is common to have multiple categorical indicators for measuring a theoretical construct of interest. A latent class model is presented that accounts for the structure in a set of correlated, categorical variables measured at discrete time periods, drawing information from these variables to form a smaller number of latent classes. The dependence of the resulting latent class model parameters on suspected factors over time is simultaneously modelled using a baseline-category logistic regression model. Estimation of the model parameters is achieved using an estimating equations procedure. A motivating example is provided from a longitudinal study of suspected linkages between monitoring or supervision by parents and the occurrence of drug use behaviours in an epidemiologic sample of school-attending youths.

Cognitive risk factors and suicide attempts among formerly hospitalized adolescents: a prospective naturalistic study.

OBJECTIVE: To examine the relationship between cognitive variables and time until suicide attempts among 180 adolescents who were monitored for as much as 6.9 years after discharge from an inpatient psychiatry unit. METHOD: In a prospective naturalistic study, adolescents were assessed at the time of their psychiatric hospitalization and semiannually thereafter. Suicidal behavior at index hospitalization and over the follow-up period was assessed with semistructured psychiatric diagnostic interviews. At hospitalization, cognitive risk factors were assessed with a problem-solving task and with questionnaires assessing hopelessness, expectations for posthospitalization suicidal behavior, reasons for living, and dysfunctional attitudes. RESULTS: Expectations about future suicidal behavior were related to posthospitalization suicide attempts. Among youths with previous suicide attempts, higher levels of hopelessness were associated with increased risk, and greater survival and coping beliefs were associated with decreased risk for posthospitalization suicide attempts. Hopelessness and survival and coping beliefs were not related to posthospitalization attempts among adolescents without prior suicidal behavior, and hopelessness was not predictive after controlling for overall severity of depression. CONCLUSIONS: Expectations for suicidal behavior, hopelessness, and survival and coping beliefs provide important prognostic information about later suicidal behavior and should be targeted in interventions with suicidal youths.

A managed behavioral health organization operated by an academic psychiatry department.

As a means of adapting to managed care, the psychiatry department at Wake Forest University developed a managed behavioral health organization (MBHO) to manage the care of enrollees in QualChoice, the health maintenance organization of the Wake Forest University Baptist Medical Center. Before the academic MBHO was created, care was managed by a for-profit MBHO. In this case study, financial and utilization data were obtained from both MBHOs and from QualChoice. The data confirm that the academic MBHO was able to offer competitive rates for its services. It also was able to increase enrollees' use of the medical center's own providers and facilities by making more referrals than were made by the for-profit MBHO. Developing a managed behavioral health organization can allow academic psychiatry departments, either individually or as consortia, to preserve the patient base they require for teaching, research, and financial stability.

Physical activity, functional limitations, and disability in older adults.

OBJECTIVES: To explore initially how low levels of physical activity influence lower body functional limitations in participants of the Longitudinal Study of Aging. Changes in functional limitations are used subsequently to predict transitions in the activities of daily living/instrumental activities of daily living (ADL/IADL) disability, thus investigating a potential pathway for how physical activity may delay the onset of ADL/IADL disability and, thus, prolong independent living. DESIGN: Analysis of a complex sample survey of US civilian, noninstitutionalized population aged 70 years and older in 1984, with repeated interviews in 1986, 1988, and 1990. SETTING AND PARTICIPANTS: Analyses concentrated on 5151 men and women targeted for interview at all four LSOA interviews. MEASUREMENTS: Characteristics used in analyses: gender, age, level of physical activity, comorbid conditions including the presence of hypertension, diabetes, arthritis, and atherosclerotic heart disease, levels of functional limitations, and ADL/IADL disability. RESULTS: Transitional models provide evidence that older adults who have varying levels of disability and who report at least a minimal level of physical activity experience a slower progression in functional limitations (OR = .45, P < .001 for severe vs less severe limitations). This low level of physical activity, through its influence on changes in functional limitations, is shown to slow the progression of ADL/IADL disability. CONCLUSIONS: Results from analyses provide supporting evidence that functional limitations can mediate the effect that physical activity has on ADL/IADL disability. These results contribute further to the increasing data that seem to suggest that physical activity can reduce the progression of disability in older adults.

Contributions of acute bouts of vigorous physical activity to explaining diurnal variations in feeling states in active, middle-aged women.

This study describes diurnal variations in feeling states in 84 women as a function of involvement in physical activity. Women completed feeling state checklists before and after bouts of vigorous physical activity that lasted a minimum of 20 min and on a stratified random-sampling protocol in response to a stimulus from an electronic pager. Participants self-reported the date, the time of day, the stimulus for responding, their current feeling states, and their ongoing activity. A total of 7,295 complete mood and activity reports were recorded in response to pager calls that were further coded into experience samplings that occurred on a nonexercise day, prior to exercise on an exercise day, and following exercise on an exercise day. Multilevel modeling analyses showed that in samplings recorded following exercise on exercise days, positive engagement, revitalization, and tranquility were elevated in comparison with predicted diurnal patterns.

Mixed effects logistic regression models for longitudinal ordinal functional response data with multiple-cause drop-out from the longitudinal study of aging.

In the context of analyzing ordinal functional limitation responses from the Longitudinal Study of Aging, we investigate the association between current functional limitation and previous year's limitation and its modification by physical activity and multiple causes of drop-out. We accommodate the longitudinal nature of the multiple causes of informative drop-out (death and unknown loss-to-follow-up) with a mixed effects logistic model. Under the proposed model with a random intercept and slope, the ordinal functional outcome and multiple discrete time survival profiles share a common random effect structure. This shared parameter selection model assumes that the multiple causes of drop-out are conditionally independent of the functional limitation outcome given the underlying random effect representing an individual's trajectory of general health status across time. Although it is not possible to fully assess the adequacy of this assumption, we assess the robustness of the approach by varying the assumptions underlying the proposed model, such as the random effects distribution and the drop-out component. It appears that between-subject differences in initial functional limitation are strongly associated with future functional limitation and that this association is stronger for those who do not have physical activity regardless of the random effects and informative drop-out specifications. In contrast, the association between current functional limitation and previous trajectory of functional status within an individual is weaker and more sensitive to changes in the random effects and drop-out assumptions.

Subjective measurement of insomnia and quality of life in depressed inpatients.

Insomnia and major depressive episodes (MDE) have each been associated with quality of life (QOL) deficits. In this study we examined insomnia as an independent predictor of QOL deficits during MDE, and used a secondary analysis of cross-sectional data. The study was based at the inpatient psychiatric ward and included 88 adults (mean age 53; 78% women). We assessed insomnia severity with the 21-item Hamilton Rating Scale for Depression (HRSD) and the Beck Depression Inventory (BDI). Measurements of QOL in the week prior to admission included activities of daily living (ADLs), instrumental ADLs (IADLs), daily living and role functioning, and relation to self and colleagues (the last two both subscales of the Basis 32). Linear regression models used the insomnia items as independent variables and the QOL measures as the dependent variables, after adjusting for age and nonsleep related depression severity. The results showed that 93% of patients endorsed insomnia on the observer-rated HRSD, and 97% endorsed sleep disturbance in the self-rated BDI. However, the insomnia items on the HRSD and BDI showed poor concurrent validity. Increasing severity of insomnia on the HDRS was associated with better QOL, while increasing severity of insomnia on the BDI was associated with worse QOL. We conclude that the BDI and HRSD do not produce equivalent measures of insomnia severity in depressed inpatients, and each insomnia measure has a unique relationship with QOL.

Effect of injected versus iontophoretic corticosteroid on the rabbit tendon.

BACKGROUND: The etiologic role of corticosteroid therapy in tendon rupture is controversial. This study compared the effects of injected versus iontophoretically delivered corticosteroid on the normal rabbit Achilles tendon. METHODS: Rabbits were divided into three treatment groups: (1) corticosteroid injections, (2) iontophoretically delivered corticosteroid, and (3) no treatment. One tendon of each rabbit in the treatment groups was treated with either drug injection or iontophoresis; the tendon of the other leg served as a control. Some tendons were used for testing elastic modulus, ultimate load, and ultimate stress, while the remaining tendons were evaluated histologically. RESULTS: Injections of either corticosteroid or saline into the tendon sheath resulted in short-term changes in tendon biomechanical characteristics and somewhat higher histologic severity scores; however, iontophoretic delivery of corticosteroid or saline did not affect either significantly. CONCLUSIONS: Iontophoresis using sterile water or corticosteroid resulted in minimal or no biochemical and histologic changes in the tendon compared with injection of either substance. The method of corticosteroid delivery may be as important as the actual drug effects on the biomechanical and histologic properties of tendons.

Suicide attempts among formerly hospitalized adolescents: a prospective naturalistic study of risk during the first 5 years after discharge.

OBJECTIVE: To examine risk for suicide attempts among 180 consecutively referred adolescents during the first 5 years after discharge from an inpatient psychiatry unit. METHOD: In a prospective naturalistic study, adolescents were assessed at psychiatric hospitalization and semiannually thereafter for up to 5 years with semistructured psychiatric diagnostic interviews and self-report questionnaires. RESULTS: Approximately 25% of the adolescents attempted suicide and no adolescents completed suicide within the first 5 years after discharge. The first 6 months to 1 year after discharge represented the period of highest risk. The number of prior attempts was the strongest predictor of posthospitalization attempts. Affective disorders by themselves did not predict later suicide attempts but were related to posthospitalization attempts when accompanied by a history of past suicide attempts. Independent of psychiatric diagnoses, severity of depressive symptoms and trait anxiety also predicted suicide attempts. Similar to the effect with affective disorders, depressive symptoms were most strongly related to posthospitalization suicidality among adolescents with a prior history of suicide attempts. CONCLUSIONS: Particularly among youths with prior suicidal behavior, clinicians should be alert to the above constellation of psychiatric predictors of posthospitalization suicidal behavior.

Effects of estrogen and estrogen-progestin on mammographic parenchymal density. Postmenopausal Estrogen/Progestin Interventions (PEPI) Investigators.

BACKGROUND: In longitudinal studies, greater mammographic density is associated with an increased risk for breast cancer. OBJECTIVE: To assess differences between placebo, estrogen, and three estrogen-progestin regimens on change in mammographic density. DESIGN: Subset analysis of a 3-year, multicenter, double-blind, randomized, placebo-controlled trial. SETTING: Seven ambulatory study centers. PARTICIPANTS: 307 of the 875 women in the Postmenopausal Estrogen/Progestin Interventions Trial. Participants had a baseline mammogram and at least one follow-up mammogram available, adhered to treatment, had not taken estrogen for at least 5 years before baseline, and did not have breast implants. INTERVENTION: Treatments were placebo, conjugated equine estrogens (CEE), CEE plus cyclic medroxyprogesterone acetate (MPA), CEE plus daily MPA, and CEE plus cyclic micronized progesterone (MP). MEASUREMENTS: Change in radiographic density (according to American College of Radiology Breast Imaging Reporting and Data System grades) on mammography. RESULTS: Almost all increases in mammographic density occurred within the first year. At 12 months, the percentage of women with density grade increases was 0% (95% CI, 0.0% to 4.6%) in the placebo group, 3.5% (CI, 1.0% to 12.0%) in the CEE group, 23.5% (CI, 11.9% to 35.1%) in the CEE plus cyclic MPA group, 19.4% (CI, 9.9% to 28.9%) in the CEE plus daily MPA group, and 16.4% (CI, 6.6% to 26.2%) in the CEE plus cyclic MP group. At 12 months, the odds of an increase in mammographic density were 13.1 (95% CI, 2.4 to 73.3) with CEE plus cyclic MPA, 9.0 (CI, 1.6 to 50.1) with CEE plus daily MPA, and 7.2 (CI, 1.3 to 40.0) with CEE plus cyclic micronized progesterone compared with CEE alone. CONCLUSIONS: Further study of the magnitude and meaning of increased mammographic density due to use of estrogen and estrogen-progestins is warranted because mammographic density may be a marker for risk for breast cancer.

Estimating equations for a latent transition model with multiple discrete indicators.

This paper proposes a two-part model for studying transitions between health states over time when multiple, discrete health indicators are available. The includes a measurement model positing underlying latent health states and a transition model between latent health states over time. Full maximum likelihood estimation procedures are computationally complex in this latent variable framework, making only a limited class of models feasible and estimation of standard errors problematic. For this reason, an estimating equations analogue of the pseudo-likelihood method for the parameters of interest, namely the transition model parameters, is considered. The finite sample properties of the proposed procedure are investigated through a simulation study and the importance of choosing strong indicators of the latent variable is demonstrated. The applicability of the methodology is illustrated with health survey data measuring disability in the elderly from the Longitudinal Study of Aging.

A Modified Exercise-induced Feeling Inventory for Chronic Training and Baseline Profiles of Participants in the Activity Counseling Trial.

An earlier study reported on the development of a scale to measure feeling states during acute bouts of exercise: the Exercise-induced Feeling Inventory (EFI-A). The present study reports on the psychometric properties of a revised scale to assess responses to habitual or chronic physical activity: the EFI-C. The EFI-C was administered during baseline testing to 830 sedentary men and women patients with a mean age of 51.5 years. Factor analytic procedures revealed that the EFI-C consisted of two factors, one assessing pleasant feeling states and a second that taps the unpleasant experience of physical exhaustion. Both subscales have excellent internal consistency reliability coefficients (0.90) and are reasonably stable over time, having test-retest coefficients in excess of 0.70. The scales correlated in expected directions with related constructs and in preliminary analyses showed an anticipated pattern of sensitivity to physical activity interventions. Mean scores for various demographic groups are reported. Future research should examine whether the EFI-C is a predictor of adherence to physical activity and its potential role in mediating the positive mental health effects of physical activity.

Symptom relief and side effects of postmenopausal hormones: results from the Postmenopausal Estrogen/Progestin Interventions Trial.

OBJECTIVE: To assess pair-wise differences between placebo, estrogen, and each of three estrogen-progestin regimens on selected symptoms. METHODS: This was a 3-year, multicenter, double-blind, placebo-controlled trial in 875 postmenopausal women aged 45-64 years at baseline. Participants were assigned randomly to one of five groups: 1) placebo, 2) daily conjugated equine estrogens, 3) conjugated equine estrogens plus cyclical medroxyprogesterone acetate, 4) conjugated equine estrogens plus daily medroxyprogesterone acetate, and 5) conjugated equine estrogens plus cyclical micronized progesterone. Symptoms were self-reported using a checklist at 1 and 3 years. Factor analysis reduced 52 symptoms to a set of six symptom groups. RESULTS: In intention-to-treat analyses at 1 year, each active treatment demonstrated a marked, statistically significant, protective effect against vasomotor symptoms compared with placebo (odds ratios [ORs] 0.17-0.28); there was no additional benefit of estrogen-progestin over estrogen alone. Only progestin-containing regimens were significantly associated with higher levels of breast discomfort (OR 1.92-2.27). Compared with placebo, women randomized to conjugated equine estrogens reported no increase in perceived weight. Those randomized to medroxyprogesterone acetate reported less perceived weight gain (OR 0.61-0.69) than placebo. Anxiety, cognitive, and affective symptoms did not differ by treatment assignment. Analyses restricted to adherent women were not materially different than those using intention-to-treat, except that women adherent to medroxyprogesterone acetate and micronized progesterone regimens reported fewer musculoskeletal symptoms (OR 0.62-0.68). CONCLUSION: These results confirm the usefulness of post-menopausal hormone therapy for hot flashes, show convincingly that estrogen plus progestin causes breast discomfort, and demonstrate little influence of postmenopausal hormones on anxiety, cognition, or affect.

Antioxidant nutrient intake and diabetic retinopathy: the San Luis Valley Diabetes Study.

OBJECTIVE: Diabetic retinopathy (DR) is a major cause of visual impairment and blindness in adults. Antioxidant nutrients, such as vitamins C and E and beta-carotene, may be protective of some eye disorders, such as cataract and age-related macular degeneration, but a relationship between these nutrients and DR has yet to be defined. The purpose of this study was to examine the relation between dietary and supplement intakes of vitamins C, E, and beta-carotene and the risk of DR. DESIGN: Both cross-sectional and longitudinal data were collected from participants in the San Luis Valley Diabetes Study, including non-Hispanic white and Hispanic adults in southern Colorado. PARTICIPANTS: A total of 387 participants with type 2 diabetes completed at least 1 complete retinal examination and 24-hour dietary recall (including vitamin supplement use). MAIN OUTCOME MEASURES: Type 2 diabetes was defined according to World Health Organization criteria. DR was assessed by retinal photographs, using the Airlie House criteria to classify DR as none, background, preproliferative, or proliferative. Data for both eyes, from up to three clinic visits per participant, were used for analysis. Ordinal logistic regression analysis was used, taking advantage of multiple clinic visits by individual participants and observations from both eyes, to assess the risk for increased DR severity over time as a function of changes in intake of vitamin C, vitamin E, and beta-carotene. Six categories of intake for each nutrient (first to fourth quintiles and ninth and tenth deciles) were considered to ascertain any potential threshold effect. Analyses accounted for age, duration of diabetes, insulin use, ethnicity, glycated hemoglobin, hypertension, gender, and caloric intake. RESULTS: An increase over time in vitamin C intake from the first to ninth deciles was associated with a risk for increased severity of DR (odds ratio = 2.21, P = 0.01), although excess risk was not observed for the tenth decile or the second through fourth quintiles compared to the first quintile. Increased intake of vitamin E was associated with increased severity of DR among those not taking insulin (odds ratios = 2.69, 2.59, 3.33, 5.65, 3.79; P < 0.02, for an increase over time from the first to the second through fourth quintiles and ninth and tenth deciles, respectively). Among those taking insulin, increased intake of beta-carotene was associated with a risk for severity of DR (odds ratio = 3.31, P = 0.003, and 2.99, P = 0.002, respectively, for the ninth and tenth deciles compared to the first quintile). CONCLUSIONS: No protective effect was observed between antioxidant nutrients and DR. Depending on insulin use, there appeared to be a potential for deleterious effects of nutrient antioxidants. Further research is needed to confirm associations of nutrient antioxidant intake and DR.

Psychiatric diagnoses of previous suicide attempters, first-time attempters, and repeat attempters on an adolescent inpatient psychiatry unit.

OBJECTIVE: To compare psychiatric diagnoses of hospitalized adolescents who (a) have made previous but no recent suicide attempts, (b) have recently made their first suicide attempt, (c) have recently made a second or subsequent attempt, or (d) have never made an attempt. METHOD: Semistructured psychiatric diagnostic interviews were used to determine psychiatric diagnoses and history of recent and previous suicidal behavior of 269 consecutively admitted adolescents to an inpatient psychiatric facility. Forty-nine previously suicidal youths, 28 first-time attempters, and 33 repeat attempters were compared with 159 nonsuicidal youths in prevalence of Axis I psychiatric disorders and psychiatric comorbidity with affective disorder. RESULTS: Previous attempters and repeat attempters both reported more affective disorders, whereas first-time attempters reported more adjustment disorders than nonsuicidal youths. Previous attempters and nonsuicidal youths reported the most externalizing disorders. CONCLUSIONS: Previous attempters on an inpatient unit have multiple psychiatric problems. Like repeat attempters, they often are depressed, but like nonsuicidal youths, they also exhibit significant externalizing behaviors. Interventions with these adolescents should focus not only on immediate presenting problems, but also on ameliorating their long-term risk of posthospitalization suicidal behavior.

The Women's Health Initiative Memory Study (WHIMS): a trial of the effect of estrogen therapy in preventing and slowing the progression of dementia.

Evidence from animal, human cross-sectional, case-control, and prospective studies indicate that hormone replacement therapy (HRT) is a promising treatment to delay the onset of symptoms of dementia. The Women's Health Initiative Memory Study (WHIMS) is the first double-masked, randomized, placebo-controlled, long-term clinical trial designed to test the hypothesis that HRT reduces the incidence of all-cause dementia in women aged 65 and older. WHIMS, an ancillary study to the Women's Health Initiative (WHI) funded by the National Institutes of Health, will recruit a subgroup of women aged 65 and older from among those enrolling in the HRT trial of the WHI. The WHI clinical centers and 10 affiliated satellites plan to enroll approximately 8300 women into WHIMS over a 2-year period. Participants will be followed annually for 6 years, receiving cognitive assessments via the Modified Mini-Mental State (3MS) Examination. Women who screen positively for cognitive impairment on the basis of an educational and age-adjusted 3MS cutpoint proceed to more extensive neuropsychological testing and neurologic evaluation. Each woman suspected to have dementia then undergoes a series of laboratory tests that confirm the clinical diagnosis and classify the type of dementia. WHIMS is designed to provide more than 80% statistical power to detect a 40% reduction in the rate of all-cause dementia, an effect that could have profound public health implications for older women's health and functioning.

Effect of hormone replacement therapy on self-reported cognitive symptoms: results from the Postmenopausal Estrogen/Progestin Interventions (PEPI) trial.

OBJECTIVE: To describe self-reported cognitive changes in 875 postmenopausal women aged 45-64 years and assigned randomly to hormone therapy (either estrogen alone or estrogen in combination with a progestin). METHODS: A 3-year placebo-controlled trial which included self-report data on problems with forgetfulness, concentration and distraction in groups of women assigned randomly to placebo, estrogen alone or estrogen plus one of three progestin regimens. RESULTS: Women assigned to any active treatment were consistently less likely to report cognitive symptoms than women assigned to placebo, but these results were not statistically significant. When compared with women assigned to estrogen plus any progestin, women assigned to estrogen alone had a significant increased risk for reporting problems with forgetfulness at follow-up (odds ratio, OR = 1.47). In the absence of problems with distraction at baseline, women assigned to estrogen alone were significantly less likely to report problems with distraction at follow-up, compared to women assigned to estrogen plus any progestin (OR = 0.36). Assignment to a continuous progestin regimen in combination with estrogen was marginally associated with an increased risk for reporting concentration problems at follow-up, compared to cyclic progestin regimens (OR = 1.63). CONCLUSIONS: These results provide some evidence to support the hypothesis that estrogen improves memory, but findings are not statistically significant in this healthy middle-aged cohort. These data suggest that estrogen in combination with any progestin confers a decreased risk for reporting forgetfulness at follow-up, compared to estrogen alone. However, there is evidence that distraction problems reported at follow-up were side-effects of progestin. There is also some evidence that women administered progestins cyclically were at lower risk for reporting cognitive symptoms at follow-up, particularly concentration problems.

Latent Transition Modeling of Progression of Health-Risk Behavior.

Longitudinal studies are helpful for understanding the complex progression of health-risk behavior over time and for identifying risk factors amenable to intervention. This article focusses on methods for modeling transitions between health-risk states over time when .are common multiple indicators of health-risk are available. Multiple measures of health-rick in studies which utilize questionnaires and surveys involving a series of self-report questions ach providing information regarding health-risk. A latent transition model is presented as am alternative to approaches that analyze indicators separately or use summative indices. These approaches ignore both the correlation between indicators and the multidimensional structure of health-risk. In the present article, transitions between latent health-risk states are modeled using a logistic regression model for nominal responses. A two-stage estimation procedure which is an estimating equations analogue of the pseudo-likelihood method is applied so that the complexity of full maximum likelihood is avoided and standard error calculation is straightforward. This procedure is applied to self-report data on weapons carrying behavior in an urban sample of schoolchildren followed annually for five years.