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PubMed1997

Religion among disabled and nondisabled persons II: attendance at religious services as a predictor of the course of disability.

Does religious involvement influence changes in physical health? We perform a longitudinal analysis of the effect of religious participation on functioning over a 12-year follow-up period, in a large, prospective, representative sample of elderly persons from New Haven, Connecticut, a religiously diverse community. To examine the possibility that disability or changes in disability may be affecting religious involvement, we perform a second longitudinal analysis of changes in religious practices. Finally, we ask whether psychosocial correlates explain the effect of religious involvement on disability. Findings are (a) that attendance at services is a strong predictor of better functioning, even when intermediate changes in functioning are included, (b) that health practices, social ties, and indicators of well-being reduce, but do not eliminate these effects, and (c) that disability has minimal effects on subsequent attendance. The findings illustrate the short- and long-term importance of religious participation to the health and well-being of elderly people, and suggest a particular significance for religious participation in the lives of disabled elders.

Aged↗

PubMed1993

Comparison of methods for the analysis of longitudinal interval count data.

Longitudinal studies are often concerned with estimating the recurrence rate of a non-fatal event. In many cases, only the total number of events occurring during successive time intervals is known. We compared a mixed Poisson-gamma regression method proposed by Thall and a quasi-likelihood method proposed by Zeger and Liang for the analysis of such data, in the case where the mean was correctly specified, using simulation techniques with large samples. Both methods produced similar standard errors in most situations, except in the case of time-dependent covariates with non-Poisson-gamma data where they were seriously underestimated by the Thall method. A simple method for discriminating between the variance forms of the two methods is described. The findings are applied to the analyses of clinical trials of non-melanoma skin cancer and familial polyposis. This study extends the findings of Breslow concerning variance misspecification in overdispersed Poisson and quasi-likelihood models to the longitudinal setting.

Adenomatous Polyposis Coli↗

PubMed1996

Alcohol consumption, gamma-glutamyl transpeptidase (GGT), and pulmonary function: a cross-sectional and longitudinal study in working men.

Epidemiological studies of the relationships between pulmonary function and reported alcohol intake showed inconsistent results. The use of biological markers of alcohol is needed. The objective of this study was to assess the relationships of alcohol consumption, assessed by a standardized questionnaire, and gamma-glutamyl transpeptidase (GGT), to forced expiratory volume in 1 sec (FEV1) level and decline over 10 years, in working men. Three hundred twenty-eight policemen aged 22-55 years were examined in 1980 (first survey) and again in 1990 (second survey). The two cross-sectional analyses used the 1980 data and the 1990 data separately. Longitudinal analysis used 1980 alcohol consumption and GGT values, and 10-year FEV1 decline. In both cross-sectional surveys, elevated alcohol consumption was significantly associated with impaired age-adjusted and height-adjusted FEV1. Further adjustment for smoking habit, education level, and asthmatic status did not alter these results. An increase of 25 g/day of alcohol was associated with 50.0 ml (95% confidence interval: 1.5 to 98.5) and 55.3 ml (95% confidence interval: 7.8 to 102.8) decrease of corresponding multivariate-adjusted FEV1 in 1980 and in 1990, respectively. GGT was also negatively associated with FEV1 in both cross-sectional surveys. Similar patterns of associations were also observed between vital capacity measurements and alcohol variables. In the longitudinal analysis, there was no relationship between either alcohol consumption or GGT and FEV1 decline. Findings suggest that alcohol consumption was associated with impaired lung function, but there was no evidence of accelerated FEV1 decline over 10 years related to alcohol consumption in this "healthy" population of middle-aged men.

Age Factors↗

PubMed2004

The application of multilevel modeling in the analysis of longitudinal periodontal data--part II: changes in disease levels over time.

BACKGROUND: The aim of this study was to investigate the longitudinal relationships between the outcome measurements of changes in lifetime cumulative attachment loss (cLCAL) and changes in probing depth (cPD) in relation to potential risk factors or other risk markers for periodontal disease progression from a cohort of 100 young males. In order to account for the hierarchical data structure, and to explore explicitly the site, tooth, and subject levels simultaneously, multilevel modeling was undertaken. METHODS: The analyses were undertaken in two parts. Within a previous article, the absolute levels of disease were analyzed in relation to potential risk factors; within this article, changes in disease are analyzed in relation to these factors. Each analytical approach yielded substantively different insights. RESULTS: Subject-level risk factors had limited predictive value for cLCAL/cPD throughout the 30-month observation period. Tooth position demonstrated a near linear relationship for both outcomes, with disease increasing from anterior to posterior teeth. Supragingival plaque had no significant effect on cLCAL/cPD, while subgingival calculus and bleeding on probing were negatively associated with cLCAL/cPD. In contrast to the outcomes LCAL/PD, supragingival calculus had no significant protective effect on cLCAL/cPD. There was no significant influence of smoking in this cohort. CONCLUSIONS: This study provides, for a relatively young cohort, considerable insights into the factors associated with longitudinal patterns of early-life periodontal disease at all levels of the natural hierarchy of sites within teeth within subjects. Furthermore, it is demonstrated how multilevel modeling can provide considerable insight into some of the inconsistencies and controversies found in the previous periodontal literature.

Adolescent↗

PubMed1998

Longitudinal cohort analysis of lethal prostate cancer progression in transgenic mice.

PURPOSE: Human prostate cancer is variably lethal, shows heterogeneous progression, and exhibits a spectrum of histopathology. Traditional rodent models of prostate cancer lack these characteristics. An alternative, autochthonous model of prostate cancer consists of transgenic mice which develop prostate cancer due to prostatic expression of SV40 T antigen. Lethal progression of such cancers in individual mice has not been previously characterized. Studies were undertaken to characterize the longitudinal progression of prostate cancers in these transgenic mice. METHODS: A prospective longitudinal cohort study was undertaken to characterize prostate cancer volume, progression, lethality, and histological heterogeneity in a transgenic mouse model of prostatic adenocarcinoma. Fifty-one transgenic mice were followed prospectively to determine the age at onset of palpable tumor and age at cancer-related death. Tumor volume was followed longitudinally by magnetic resonance imaging (MRI) in a subset of these mice and lethal cancers were evaluated by histopathology. RESULTS: Primary tumors became palpable at 10-38 weeks of age. Palpable tumors always preceded lethal progression. Cancer death followed 2-9 weeks later, and age at cancer death varied from 24 to 39 weeks of age. The histopathological changes were heterogeneous. Primary tumors were detectable by MRI before they became detectable by palpation. MRI showed that, analogous to human prostate cancers, volume of early stage primary tumors did not necessarily predict age at cancer death. CONCLUSION: Prostate cancer in transgenic mice mimics heterogeneic tumor progression in human prostate cancer, providing a uniquely relevant pre-clinical model. Tumor detection by MRI and palpation are valid surrogate measures of tumor progression in this model.

Animals↗

PubMed1989

Quantitative genetic analysis of longitudinal trends in adoption designs with application to IQ in the Colorado Adoption Project.

A factor model is presented that provides for either multivariate or developmental specification of longitudinal genetic and environmental effects in the presence of assortative mating and cultural transmission. Delta path methods are employed for the treatment of assortative mating and selective placement effects. The proportions of genetic and environmental variance and covariance attributable to assortative mating and cultural transmission are modeled explicitly. The model was applied to cognitive ability data on 493 families in the Colorado Adoption Project by means of maximum-likelihood pedigree analysis. A test of the assumption of multivariate normality of error provided an additional model criterion beyond the log-likelihood ratio statistic. No significant effects were found for cultural transmission, genetic-environmental covariance, or selective placement. The results suggest that the phenotypic stability of IQ during early childhood is largely, if not entirely, genetic in origin and that these longitudinal genetic effects can be represented most parsimoniously in the form of developmental transmission.

Adoption↗

PubMed2006

Longitudinal epitope analysis of insulin-binding antibodies in type 1 diabetes.

Autoantibodies to insulin (IAA) are one of the first markers of the autoimmune process leading to type 1 diabetes (T1D). While other autoantibodies in T1D have been studied extensively, relatively little is known about IAA and their binding specificities, especially after insulin treatment is initiated. We hypothesize that insulin antibodies (IA) that develop upon initiation of insulin treatment differ in their epitope specificities from IAA. We analysed insulin antibody binding specificities in longitudinal samples of T1D patients (n = 49). Samples were taken at clinical diagnosis of disease and after insulin treatment was initiated. The epitope specificities were analysed using recombinant Fab (rFab) derived from insulin-specific monoclonal antibodies AE9D6 and CG7C7. Binding of radiolabelled insulin by samples taken at onset of the disease was significantly reduced in the presence of rFab CG7C7 and AE9D6. rFab AE9D6 competed sera binding to insulin significantly better than rFab CG7C7 (P = 0.02). Binding to the AE9D6-defined epitope in the initial sample was correlated inversely with age at onset (P = 0.005). The binding to the AE9D6-defined epitope increased significantly (P < 0.0001) after 3 months of insulin treatment. Binding to the CG7C7-defined epitope did not change during the analysed period of 12 months. We conclude that epitopes recognized by insulin binding antibodies can be identified using monoclonal insulin-specific rFab as competitors. Using this approach we observed that insulin treatment is accompanied by a change in epitope specificities in the emerging IA.

Adolescent↗

PubMed2006

Physical and psychological functioning of daily living in relation to physical activity. A longitudinal study among former elite male athletes and controls.

BACKGROUND AND AIMS: Physical exercise plays an important role in the prevention and reduction of disabilities in elderly people. The aim of this study was to determine the role of physical activity in the physical and psychological functioning of daily living in a cohort of former elite male athletes representing different sports, and controls of middle and old age. METHODS: Subjects were 664 former elite male athletes (mean age 64.4 years) and 500 controls (62.0 years) in middle and old age. Subjects were mailed "Physical activity and health survey" questionnaires in 1985 and 1995. The primary outcomes the physical and psychological functioning of daily living--were assessed in 1995 using items from the Mini-Finland Health Survey. Logistic regression was used for longitudinal as well as cross-sectional analyses to estimate odds ratios (OR) for poor physical and psychological functioning of daily living in relation to recreational physical activity adjusted for age, sport group, life-style, BMI, mood, chronic diseases, personality characteristics, life-events and socio-economic status. RESULTS: In the longitudinal analysis, low levels of physical activity (lowest MET quintile vs highest quintile) in 1985 (OR 4.91, 95% confidence interval (CI) 2.02-11.9), older age (> or =70 yrs vs under 60 yrs OR 9.93, 95% CI 4.90-20.2), depression (OR 2.03, 95% CI 1.01-4.09) and anxiety in 1995 (OR 2.67, 95% CI 1.34-5.32) increased the risk of poor physical functioning of daily living in 1995, whereas an increase in a physical activity between 1985-1995 (OR 0.89, 95% CI 0.83-0.95) protected against poor physical functioning of daily living. A history of participating in specific types of sports, especially among certain power sports (weight-lifting and track & field throwers) (OR 0.19, 95% CI 0.06-0.60) and team sports (OR 0.34, 95% CI 0.15-0.81) did reveal a significant protective effect against poor psychological functioning of daily living in the longitudinal analysis. CONCLUSIONS: This study suggests that an increase in physical exercise supports physical daily functionality. A specific history of sports participation promotes psychological well-being at an older age.

Activities of Daily Living↗

PubMed2006

Mixture analysis of longitudinal binary data.

The dependence of longitudinal binary outcomes on covariates and the covariation observed between them is often modelled by (multivariate) logistic and probit models, respectively, assuming specified association structure or random effects. Alternatively, latent class models may be used that capture the covariation by assuming heterogeneity of the observational units regarding their reaction tendencies while postulating independence within classes. In the presence of a few categorical covariates, the multi-group method of latent class analysis allows one to relate the class sizes and the class-specific response probabilities to these covariates. Wheeze data from the Harvard Six-Cities study on respiratory health are a typical example for such a situation: at four occasions, the wheeze status of 537 children was examined, 187 among them exposed to maternal smoking and 350 not exposed. Thus, there is a single binary covariate (maternal smoking versus no maternal smoking) making easily applicable the multi-group method of latent class analysis. Based on a series of unrestricted and restricted models having up to three classes for the exposed and not-exposed subgroup each, no statistically significant effect of maternal smoking on children's wheeze status could be substantiated. Moreover, it was not possible to show statistically significant difference at all between the two distributions of wheeze patterns collected from exposed and not-exposed children.

Child↗

PubMedDate not supplied

Short implants--an analysis of longitudinal studies.

PURPOSE: The purpose of this study was to consider the therapeutic decision whether to use advanced surgery or short implants based on data concerning the use of these implants found in follow-up studies. MATERIALS AND METHODS: The MEDLINE database was consulted for follow-up studies published between the years 1980 and 2004. For those studies that met the inclusion and exclusion criteria, data concerning the number of implants 7, 8.5, or 10 mm long placed and lost, the time at which the failure occurred, and related risk factors were gathered for 33 studies arranged in tables and subjected to analysis. The studies included 16,344 implant placements with 786 failures (4.8%). Implants were analyzed according to the time of failure (i.e., before or after prosthesis seating) and risk factors implicated in the failures. RESULTS: The total rate of failures was 4.8%. Implants 3.75 mm wide and 7 mm long failed at a rate of 9.7%, compared to 6.3% for 3.75 x 10-mm implants. It was found that 54.9% of failures occurred before the prosthesis connection. Finally, 66.7% of all failures were attributed to poor bone quality, 45.4% to the location (maxilla or mandible), 27.2% to occlusal overload, 24.2% to location within the jaw, and 15.1% to infections (an implant could be associated with multiple risk factors). DISCUSSION: The analysis revealed that among the risk factors, poor bone quality in association with short implants seemed to be relevant to failure. The use of implants 4 mm in diameter appeared to minimize failure in these situations. The 3.75 x 7-mm implant presented the highest failure rate (9.7%) of 1894 implants analyzed (excluding implant designs with higher failure rates but few total implants). CONCLUSION: Short implants should be considered as an alternative to advanced bone augmentation surgeries, since surgeries can involve higher morbidity, require extended clinical periods, and involve higher costs to the patient.

Alveolar Process↗

PubMedDate not supplied

Longitudinal course of depressive symptomatology after a cardiac event: effects of gender and cardiac rehabilitation.

OBJECTIVE: Recent research has linked depression to cardiac mortality, and shown a high burden of persistent depressive symptomatology among cardiac patients. The objective of this study was to longitudinally examine the prevalence and course of depressive symptomatology among women and men for 1 year after a cardiac event, and the effect of cardiac rehabilitation (CR) on this trajectory. METHODS: Nine hundred thirteen unstable angina (UA) and myocardial infarction patients from 12 coronary care units were recruited, and follow-up data were collected at 6 and 12 months. Measures included CR participation, medication usage, and the Beck Depression Inventory (BDI). The longitudinal analysis was conducted using SAS PROC MIXED. RESULTS: At baseline there were 277 (31.3%) participants with elevated depressive symptomatology (BDI > or = 10), 131 (25.2%) at 6 months, and 107 (21.7%) at 1 year. Overall, approximately 5% were taking an antidepressant medication, and 20% attended CR over their year of recovery. Participants with greater depressive symptomatology participated in significantly fewer CR exercise sessions (r = -0.19, p = .02), and minimal psychosocial interventions were offered. The longitudinal analysis revealed that all participants experienced reduced depressive symptomatology over their year of recovery (p = .04), and younger, UA participants with lower family income fared worst (ps < 0.001). CR did not have an effect on depressive symptomatology over time, but women who attended CR were significantly more depressed than men (p = .01). CONCLUSION: Depressed cardiac patients are undertreated and their symptomatology persists for up to 6 months. CR programs require greater resources to ensure that depressed participants adhere to exercise regimens, and are screened and treated for their elevated symptomatology.

Age Factors↗

PubMed1977

Reproductive failure in aged CBF1 male mice: interrelationships between pituitary gonadotropic hormones, testicular function, and mating success.

Circulating pituitary gonadotropins and testicular function were examined in aged CBF1 male mice using two experimental designs: a) a longitudinal analysis of 2 to 30-month-old males, and b) a direct comparison of weight-matched, sexually-active vs. sexually-inactive 24-month-old males, all of whom were relatively robust. Measurements included serum concentrations of testosterone, follicle stimulating hormone, and luteinizing hormone, gonadotropic responsiveness to castration, success in a 4-day mating test, testicular sperm content, and reproductive organ weights. The longitudinal analysis showed progressive losses in mating success and sperm production between 18 and 30 months, changes which were correlated with decreased levels of serum LH and testosterone but not with FSH. The direct comparison of robust, sexually-active vs.-inactive males provided a better design for identifying reproductive-specific effects of aging, as opposed to debilitative changes that are general to several supporting systems. Such comparisons in 24-month-old CBF1 males suggest the existence of a subpopulation of mice in which reproductive failure is specifically correlated with a loss in the episodic release of LH.

Aging↗

PubMed2002

Caries reductions between 1995, 1997 and 1999 in preschool children in Diadema, Brazil.

AIMS: This study aimed to assess changes in caries prevalence and severity in preschool children in Diadema, Brazil. METHODS: Three cross-sectional surveys were conducted, using the same protocol, in 1995, 1997 and 1999. The first survey included children aged 5-35 months, and the second and third, children aged 5-59 months. Participants were selected from all children attending a National Day of Children's Vaccination; 548, 992 and 690 in 1995, 1997 and 1999, respectively. This approach was sound as uptake rates for all years studied were above 90% for children aged between 1 and 59 months in all three surveys. Caries experience was measured using the World Health Organization (WHO) def index. Time-lag and quasi-longitudinal analysis were carried out. RESULTS: Time-lag analysis showed a marked and statistically significant decline in the prevalence and severity of coronal and rampant caries between 1995 and 1999. There were reductions of 36.5% in the prevalence of caries in 2-year-olds between 1995 and 1997 (P < 0.002) and 36.0% between 1997 and 1999 (P = 0.041). The mean def-s at the same age decreased from 2.0 in 1995 to 1.1 in 1997 (P < 0.001) and to 1.0 in 1999 (P > 0.05). The quasi-longitudinal analysis showed a statistically significantly increase in the percentage of children with caries between 1995 and 1997 and 1997 and 1999 (P < 0.001), but not for 2-year-old children between 1995 and 1997 (P > 0.05). The same pattern was observed for severity of dental caries. CONCLUSION: Oral health in preschool children in Diadema improved markedly during 1995-99.

Age Factors↗

PubMed1993

Quantitative EMG analysis and longitudinal nerve conduction studies in a Refsum's disease patient.

A patient with aosmia and night blindness had repeated clinical and electrophysiological examinations during a 21-year period. Within the first 11 years, he experienced two subacute episodes of numbness with weakness and ataxia. Over the 10 ensuing years, no additional functional disability appeared. We looked retrospectively for a correlation between repeated manual muscle scoring and different nerve conduction parameters. Further studies were done in order to estimate reinnervation in proximal and distal muscles and to assess autonomic functions. A direct relationship was found between the magnitude of muscle weakness and the amplitude of compound muscle action potentials, whereas nerve conduction velocities were inhomogeneously reduced but almost unchanged over time. Parasympathetic tests were normal but sympathetic skin responses were absent. As estimated by macro-EMG and turns-amplitude analysis the compensatory reinnervation was very high. We conclude that, in Refsum's disease, recurrent segmental demyelination of a significant portion of the motor units can occur in parallel with exacerbations of weakness, and that a considerable degree of progressive motor and sudoromotor axonal loss can be found although there is an apparent long-term clinical stabilization of the neuropathy.

Action Potentials↗

PubMed1984

Muscle capillary basement-membrane thickness and long-term glycemia in type I diabetes mellitus.

We explored the relation between the thickness of the quadriceps-muscle capillary basement membrane and the glycemia level in 102 young patients with Type I diabetes (median age, 17 years; range, 12 to 29). Membrane thickness was measured in serial biopsy specimens obtained after two consecutive 2 1/2-year observation periods, and glycemia was assessed in terms of glycosylated hemoglobin and fasting blood glucose levels determined at eight-week intervals. An association between membrane thickness and glycemia level was apparent in both cross-sectional and longitudinal analysis. Cross-sectional analysis of data on 39 postpubertal patients (growth less than 1.0 cm during the five years) showed a positive association of membrane thickness to glycosylated hemoglobin (r = 0.53, P = 0.0002) and blood glucose values (r = 0.37, P = 0.01) averaged over the antecedent 2 1/2-year period. By contrast, in 32 pubertal patients (growth greater than 7.5 cm) there was a significant negative association of membrane thickness to both glycosylated hemoglobin (r = -0.40, P = 0.01) and blood glucose (r = -0.42, P = 0.009). In longitudinal analysis, there was no correlation between changes in membrane thickness and average glycemia levels during the two follow-up periods in 32 pubertal patients (for glycosylated hemoglobin, r = 0.11; P = 0.25), but in the postpubertal group (n = 20) there was a significant positive covariation (r = 0.57, P = 0.0004). The data indicate that in postpubertal diabetic patients, the thickness of the muscle capillary basement membrane is positively related to the level of glycemia, but this relation does not obtain in the pubertal state.

Adolescent↗

PubMed2000

Sib-pair linkage analysis of longitudinal changes in lipoprotein risk factors and lipase genes in women twins.

Based on longitudinal twin data in women, we have previously demonstrated a genetic influence on changes in lipoprotein risk factors, blood pressure measurements, and body mass index over a decade. The present study examined the linkage between changes in lipoprotein variables and candidate genes encoding the hormone-sensitive lipase (HSL), hepatic lipase (HL), and lipoprotein lipase (LPL). The sample consisted of 126 dizygotic (DZ) pairs of women twins who participated in the two examinations of the Kaiser Permanente Women Twins Study, performed a decade apart. Using quantitative sib-pair linkage analysis, a linkage was demonstrated between the locus for hormone-sensitive lipase and age-adjusted changes in plasma triglyceride (P = 0.015), which became more significant after adjustment for environmental factors and the exam-1 level (P = 0.005). There was also evidence suggesting linkage between the locus for hepatic lipase and changes in triglyceride (P = 0.023), but no linkage was detected for lipoprotein lipase and changes of lipid levels with time. These findings suggest that variation at these candidate gene loci may underlie a portion of the intraindividual variations in these coronary heart disease (CHD) risk factors, and that studies to identify the functional variants could provide new insights into genetic susceptibility to cardiovascular disease.

Adult↗

PubMed2004

Does breastfeeding protect against pediatric overweight? Analysis of longitudinal data from the Centers for Disease Control and Prevention Pediatric Nutrition Surveillance System.

OBJECTIVE: To examine whether increasing duration of breastfeeding is associated with a lower risk of overweight in a low-income population of 4-year-olds in the United States. METHODS: Visit data were linked to determine prospectively the duration of breastfeeding (up to 2 years of age) and weight status at 4 years of age. Overweight among 4-year-old children was defined as a body mass index (BMI)-for-age at or above the 95th percentile based on the 2000 Centers for Disease Control and Prevention growth charts. Logistic regression was performed, controlling for gender, race/ethnicity, and birth weight. In a subset of states, links to maternal pregnancy records also permitted regression analysis controlling for mother's age, education, prepregnancy BMI, weight gain during pregnancy, and postpartum smoking. Data from the Pediatric Nutrition Surveillance System, which extracts breastfeeding, height, and weight data from child visits to public health programs, were analyzed. In 7 states, data were linked to Pregnancy Nutrition Surveillance System data. A total of 177 304 children up to 60 months of age were included in our final pediatric-only analysis, and 12 587 were included in the pregnancy-pediatric linked analysis. RESULTS: The duration of breastfeeding showed a dose-response, protective relationship with the risk of overweight only among non-Hispanic whites; no significant association was found among non-Hispanic blacks or Hispanics. Among non-Hispanic whites, the adjusted odds ratio of overweight by breastfeeding for 6 to 12 months versus never breastfeeding was 0.70 (95% confidence interval: 0.50-0.99) and for >12 months versus never was 0.49 (95% confidence interval: 0.25-0.95). Breastfeeding for any duration was also protective against underweight (BMI-for-age below the 5th percentile). CONCLUSION: Prolonged breastfeeding is associated with a reduced risk of overweight among non-Hispanic white children. Breastfeeding longer than 6 months provides health benefits to children well beyond the period of breastfeeding.

Adult↗

PubMed1999

PTSD among bereaved parents following the violent deaths of their 12- to 28-year-old children: a longitudinal prospective analysis.

This study examined the prevalence of posttraumatic stress disorder (PTSD) among parents bereaved by the violent deaths of their 12- to 28-year-old children. A community-based sample of 171 bereaved mothers and 90 fathers was recruited by a review of Medical Examiner records and followed for 2 years. Four important findings emerged: Both parents' gender and children's causes of death significantly affected the prevalence of PTSD symptoms. Twice as many mothers and fathers whose children were murdered met PTSD caseness (full diagnostic) criteria compared with accident and suicide bereavement. Symptoms in the reexperiencing domain were the most commonly reported. PTSD symptoms persisted over time, with 21% of the mothers and 14% of the fathers who provided longitudinal data still meeting caseness criteria 2 years after the deaths. Parents who met caseness criteria for PTSD, compared with those who did not, were significantly different on multiple study variables. Both theoretical and clinical implications for the findings are discussed.

Adaptation, Psychological↗