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PubMedDate not supplied

Correlations over time between dysphoric mood and symptomatology in schizophrenia.

Monthly assessments of depression, anxiety, and positive and negative symptoms of schizophrenia were performed on 52 schizophrenic patients over periods ranging from 12 to 29 months. Data were analyzed to assess the extent to which symptoms of dysphoria (anxiety and depression) were more strongly related to negative or positive symptoms of schizophrenia. Consistent with past research using comparisons across subjects, the current longitudinal data show that there is a more consistent relationship between dysphoria and positive rather than negative symptoms.

Adult↗

PubMed2005

Disentangling the causal relationships between work-home interference and employee health.

OBJECTIVES: The present study was designed to investigate the causal relationships between (time- and strain-based) work-home interference and employee health. The effort-recovery theory provided the theoretical basis for this study. METHODS: Two-phase longitudinal data (with a 1-year time lag) were gathered from 730 Dutch police officers to test the following hypotheses with structural equation modeling: (i) work-home interference predicts health deterioration, (ii) health complaints precede increased levels of such interference, and (iii) both processes operate. The relationship between stable and changed levels of work-home interference across time and their relationships with the course of health were tested with a group-by-time analysis of variance. Four subgroups were created that differed in starting point and the development of work-home interference across time. RESULTS: The normal causal model, in which strain-based (but not time-based) work-home interference was longitudinally related to increased health complaints 1 year later, fit the data well and significantly better than the reversed causal model. Although the reciprocal model also provided a good fit, it was less parsimonious than the normal causal model. In addition, both an increment in (strain-based) work-home interference across time and a long-lasting experience of high (strain-based) work-home interference were associated with a deterioration in health. CONCLUSIONS: It was concluded that (strain-based) work-home interference acts as a precursor of health impairment and that different patterns of (strain-based) work-home interference across time are related to different health courses. Particularly long-term experience of (strain-based) work-home interference seems responsible for an accumulation of health complaints.

Adult↗

PubMed2007

Health-related quality of life profiles based on survivorship status for head and neck cancer patients.

BACKGROUND: As the methodologies for evaluating health-related quality of life (HRQOL) in head and neck cancer patients have matured over the past 10 years, there has been an increasing focus on reporting longitudinal data. These studies have primarily focused on long-term survivors. This study addresses the HRQOL of both long-term and short-term survivors. METHODS: This is a prospective, longitudinal study of 479 head and neck cancer patients followed for at least 3 years after diagnosis. Analysis of longitudinally collected HRQOL scores was based on survivorship status. RESULTS: The HRQOL for 3 survivorship groups: short-term (died <1 year), intermediate-term (died 1-3 years), and long-term survivors (alive >3 years) were different at all time points (pretreatment, 3, 6, and 12 months). Differences were greatest between the short-term and long-term survivors. Long-term survivors demonstrated the best HRQOL and an improving HRQOL trajectory at 12 months. The HRQOL of short-term survivors declined precipitously throughout all available follow-up. Intermediate-term survivors did show some improvement following treatment but had a declining HRQOL trajectory at 12 months. CONCLUSION: The HRQOL profiles of head and neck cancer patients differed significantly depending on survivorship status. Long-term HRQOL results should be analyzed within the context of the results for all of the patients eligible to have been included in the initial study cohort.

Aged↗

PubMed2005

The relative effects of hormones and relationship factors on sexual function of women through the natural menopausal transition.

OBJECTIVE: To investigate the relative effects of hormonal and relationship factors on female sexual function during the natural menopausal transition. DESIGN: Prospective population-based questionnaire study. SETTING: Interviews were conducted in the patients' homes. PATIENT(S): Four hundred thirty-eight Australian-born women aged 45-55 years who were still menstruating at baseline. Eight years of longitudinal data were available for 336 of these women, none of whom were hysterectomized. INTERVENTION(S): Hormonal levels, age, menopausal status, partner status, and feelings for partner were measured and evaluated with longitudinal structural equation modeling. MAIN OUTCOME MEASURE(S): Short personal experiences questionnaire. RESULT(S): Sexual response was predicted by prior level of sexual function, change in partner status, feelings for partner, and E2 level (R2 = .65); dyspareunia was predicted by prior level of dyspareunia and E2 level (R2 = .53); and frequency of sexual activities was predicted by prior level of sexual function, change in partner status, feelings for partner, and level of sexual response (R2 = .52). The minimum effective dose needed to increase sexual response by 10% (700 pmol/L E2) is twice that needed to decrease dyspareunia. CONCLUSION(S): Prior function and relationship factors are more important than hormonal determinants of sexual function of women in midlife.

Female↗

PubMedDate not supplied

The relationship between alcohol problems and use of tranquilizing drugs: longitudinal patterns among American women.

A previous community study of older adults (Graham et al., 1996) indicated a relationship between alcohol problems and use of tranquilizing drugs despite no relationship between alcohol consumption and tranquilizer use. The present paper explores this issue further using longitudinal data from a representative sample of American women. The results replicated previous findings of a significant relationship between alcohol problems and tranquilizer use that was unrelated to alcohol consumption. Analyses of longitudinal patterns indicated that alcohol problems in 1981 predicted subsequent use of tranquilizing drugs and that this relationship may be moderated by anxiety, with the relationship being strongest for respondents who reported few or no problems with anxiety. The results indicated no support for the relationship being due to: a pharmacological interaction of alcohol with tranquilizing drugs; use of tranquilizing drugs precipitating alcohol problems; or depression, anxiety, poor health or childhood sexual abuse being common causes of both alcohol problems and tranquilizer use. The link between alcohol problems and use of tranquilizing drugs needs to be investigated further to increase understanding of addictive behaviors.

Adult↗

PubMed2006

The utility of extended longitudinal profiles in predicting future health care expenditures.

BACKGROUND: Health care spending is highly concentrated. Prediction models that accurately identify the characteristics of individuals most likely to incur high levels of health expenditures in a subsequent year are important analytical and statistical tools. OBJECTIVES: This study examined the capacity of alternative models to predict the likelihood of incurring high levels of medical expenditures in a subsequent year. This effort also evaluated the utility of an additional year of longitudinal information. SUBJECTS: A nationally representative sample from the Medical Expenditure Panel Survey (MEPS). METHODS: The MEPS longitudinal data are used to examine the persistence of high expenditures during a 2-year period. With the unique linkage of the MEPS to the National Health Interview Survey, the utility of an additional year of data also was examined. Resultant models were evaluated in terms of sensitivity, specificity, and predictive capacity. RESULTS: Only modest marginal gains in discrimination capacity were realized from the use of extended longitudinal profiles from the National Health Interview Survey, relative to information on prior year characteristics. CONCLUSIONS: Our results highlight the continuing concentration of health care expenditures during the period 1996 to 2002 and reveal some attenuation in magnitude in the tail of this distribution over time. Further, our results provide evidence of the utility of probabilistic models as prediction tools to identify individuals likely to incur high levels of expenditures in future years. Predictive capacity does not suffer when restricted to a single year of prior information.

Adolescent↗

PubMed2002

Procedures for reliable estimation of viral fitness from time-series data.

In order to develop a better understanding of the evolutionary dynamics of HIV drug resistance, it is necessary to quantify accurately the in vivo fitness costs of resistance mutations. However, the reliable estimation of such fitness costs is riddled with both theoretical and experimental difficulties. Experimental fitness assays typically suffer from the shortcoming that they are based on in vitro data. Fitness estimates based on the mathematical analysis of in vivo data, however, are often questionable because the underlying assumptions are not fulfilled. In particular, the assumption that the replication rate of the virus population is constant in time is frequently grossly violated. By extending recent work of Marée and colleagues, we present here a new approach that corrects for time-dependent viral replication in time-series data for growth competition of mutants. This approach allows a reliable estimation of the relative replicative capacity (with confidence intervals) of two competing virus variants growing within the same patient, using longitudinal data for the total plasma virus load, the relative frequency of the two variants and the death rate of infected cells. We assess the accuracy of our method using computer-generated data. An implementation of the developed method is freely accessible on the Web (http://www.eco.ethz.ch/fitness.html).

Anti-HIV Agents↗

PubMed1993

Evaluating the effects of tubal sterilization on menstrual function: selected issues in data analysis.

We examined selected issues in data analysis in the Collaborative Review of Sterilization (CREST). CREST is a multicentre, prospective, observational study of women undergoing tubal sterilization. We analysed menstrual function after sterilization in over 5000 women who were enrolled in the period 1978-1983 and followed for 5 years with yearly follow-up interviews. To take into account the dependency among repeated responses from the same individuals, we used the generalized estimating equations (GEE) approach to longitudinal data analysis. Marginal modelling resulted in a statistically significant increase in the odds of menstrual dysfunction at 5 years after tubal sterilization. Transitional modelling produced rates of menstrual dysfunction given a woman's menstrual function at baseline, after adjusting for other baseline characteristics such as method of contraception before sterilization. To examine the direction of the bias that could result from non-random missing data, we refitted our models using imputed values. The models with imputed values showed the same trends as the original models.

Bias↗

PubMed2006

Reliability of motor development data in the WHO Multicentre Growth Reference Study.

AIM: To describe the methods used to standardize the assessment of motor milestones in the WHO Multicentre Growth Reference Study (MGRS) and to present estimates of the reliability of the assessments. METHODS: As part of the MGRS, longitudinal data were collected on the acquisition of six motor milestones by children aged 4 to 24 mo in Ghana, India, Norway, Oman and the USA. To ensure standardized data collection, the sites conducted regular standardization sessions during which fieldworkers took turns to examine and score about 10 children for the six milestones. Assessments of the children were videotaped, and later the other fieldworkers in the same site watched the videotaped sessions and independently rated performances. The assessments were also viewed and rated by the study coordinator. The coordinator's ratings were considered the reference (true) scores. In addition, one cross-site standardization exercise took place using videotapes of 288 motor assessments. The degree of concordance between fieldworkers and the coordinator was analysed using the Kappa coefficient and the percentage of agreement. RESULTS: Overall, high percentages of agreement (81-100%) between fieldworkers and the coordinator and "substantial" (0.61-0.80) to "almost perfect" (> 0.80) Kappa coefficients were obtained for all fieldworkers, milestones and sites. Homogeneity tests confirm that the Kappas are homogeneous across sites, across milestones, and across fieldworkers. Concordance was slightly higher in the cross-site session than in the site standardization sessions. There were no systematic differences in assessing children by direct examination or through videotapes. CONCLUSION: These results show that the criteria used to define performance of the milestones were similar and applied with equally high levels of reliability among fieldworkers within a site, among milestones within a site, and among sites across milestones.

Child Development↗

PubMed2001

Memory complaints as a precursor of memory impairment in older people: a longitudinal analysis over 7-8 years.

BACKGROUND: There is considerable dispute about the validity of memory complaints. While some studies find that complaints are an early indicator of dementia or cognitive decline, there are also many studies showing that complaints are more closely associated with negative affect (depression, anxiety and neuroticism). The present paper used three-wave longitudinal data to test three hypotheses: (1) that memory complaints reflect an evaluation of present and past memory performance; (2) that memory complaints predict future memory performance; and (3) that memory complaints predict current and future negative affect. METHODS: A longitudinal study was carried out with a community sample of people aged 70 and over. Participants were assessed for memory complaints, memory performance and negative affect at three waves separated by 3.6 years and 4.0 years. There were 331 persons with data on all relevant variables. The data were analysed using structural equation modelling. RESULTS: Significant paths in the structural model were found from memory performance to future memory complaints, as well as from memory complaints to future memory performance, supporting hypotheses 1 and 2. Memory complaints were associated with current negative affect, but did not predict future negative affect. CONCLUSIONS: Memory complaints do reflect perceptions of past memory performance and are also an early manifestation of memory impairment. However, current negative affect (anxiety and depression symptoms) shows the greatest association with memory complaints.

Affect↗

PubMed2002

Prognosis for gross motor function in cerebral palsy: creation of motor development curves.

CONTEXT: Lack of a valid classification of severity of cerebral palsy and the absence of longitudinal data on which to base an opinion have made it difficult to consider prognostic issues accurately. OBJECTIVE: To describe patterns of gross motor development of children with cerebral palsy by severity, using longitudinal observations, as a basis for prognostic counseling with parents and for planning clinical management. DESIGN: Longitudinal cohort study of children with cerebral palsy, stratified by age and severity of motor function and observed serially for up to 4 years during the period from 1996 to 2001. SETTING: Nineteen publicly funded regional children's ambulatory rehabilitation programs in Ontario. PARTICIPANTS: A total of 657 children aged 1 to 13 years at study onset, representing the full spectrum of clinical severity of motor impairment in children with cerebral palsy. MAIN OUTCOME MEASURES: Severity of cerebral palsy, classified with the 5-level Gross Motor Function Classification System; function, formally assessed with the Gross Motor Function Measure (GMFM). RESULTS: Based on a total of 2632 GMFM assessments, 5 distinct motor development curves were created; these describe important and significant differences in the rates and limits of gross motor development among children with cerebral palsy by severity. There is substantial within-stratum variation in gross motor development. CONCLUSIONS: Evidence-based prognostication about gross motor progress in children with cerebral palsy is now possible, providing parents and clinicians with a means to plan interventions and to judge progress over time. Further work is needed to describe motor function of adolescents with cerebral palsy.

Adolescent↗

PubMed1989

Comparison of cross-sectional and longitudinal measurements of age-related changes in bone mineral content.

Age-related, postmenopausal bone loss was examined among a cohort of Japanese-American women living in Hawaii. None of the women were using estrogens or thiazides. Cross-sectional and longitudinal measurements of bone mineral content were compared at the calcaneus, the proximal radius, and the distal radius. Cross-sectional measurements were also available for the lumbar spine. The longitudinal data showed a slowing rate of bone loss with increasing age at the radius sites. By contrast, the cross-sectional data suggested constant rates of bone loss for all ages at both radius sites and the spine. The calcaneus demonstrated a complex pattern of bone loss in both cross-sectional and longitudinal analyses. The loss rates among women in their fifties were greater than for those in their sixties. From the middle sixties onward calcaneal bone loss remained essentially constant. Because of the sustained bone loss, however, women in their seventies were actually losing greater percentages of their calcaneal bone mineral than they had in their sixties.

Aged↗

PubMed2006

Parental verbal abuse and the mediating role of self-criticism in adult internalizing disorders.

BACKGROUND: Researchers (e.g., [Gibb, B.E., 2002. Childhood maltreatment and negative cognitive styles. A quantitative and qualitative review. Clinical Psychology Review, 22 (2), 223-246]; [Rose, D.T., Abramson, L.Y., 1992. Developmental predictors of depressive cognitive styles: developmental perspectives on depression. In Cicchetti, D., Toth, S.L. (Eds.), Developmental Perspectives on Depression. Rochester symposium on developmental psychopathology, vol. 4, pp. 323-349]) have proposed that when childhood abuse is verbal (rather than sexual or physical), the child is more likely to develop a negative self-schema because the negative self-cognitions are directly supplied to the child by the abuser (e.g., "you are stupid"). METHODS: In a test of this theory in adult participants, and drawing on the National Comorbidity Survey (NCS) (N=5877), we investigate the mediating role of current levels of self-criticism on the relationship between retrospective reports of parental verbal abuse, as well as sexual and physical abuse, and adult internalizing symptoms. RESULTS: We found self-criticism, but not dependency traits, to fully mediate the relationship between childhood verbal abuse perpetrated by parents and internalizing (depression, anxiety) symptoms. On the other hand, self-criticism was only a partial mediator of the relationship between the other types of abuse and internalizing symptoms. LIMITATIONS: The NCS data is cross-sectional, which limits any firm conclusions regarding causality. While these results are suggestive that self-criticism is a mediator of the relationship between abuse and internalizing symptoms, longitudinal data are necessary to help rule out alternative explanations. CONCLUSIONS: Results of this study suggest that childhood abuse experiences, and in particular verbal abuse, may confer risk for internalizing disorders in part because verbal abuse influences the development of a self-critical style.

Adolescent↗

PubMed2000

Which source should we use to measure quality of life in children with asthma: the children themselves or their parents?

This study compares the reproducibility, construct validity and responsiveness of self-report and parent-report quality of life questionnaires How Are You (HAY) for 8-12-year-old children with asthma. A total of 228 Dutch children with asthma and their parents completed the HAY and daily recorded the child's asthma symptoms in a diary. Additionally 296 age- and -gender matched healthy children and their parents completed the generic part of the HAY. Reproducibility and responsiveness were examined in a sub-group of 80 children with asthma. In this group, three measurements were carried out, at baseline, after one week and once during the following 6 month when the clinical asthma status had changed. The within-subject standard deviations (SD) of three dimensions (physical activities, social activities, self-management) differed significantly (p < 0.05) in favour of the parent-version, indicating that the reproducibility of the parent version was better than that of the child version. The mean score-differences between children with asthma and healthy children as reported by parents did not significantly differ from those reported by children, except for cognitive activities (e.g. be able to concentrate on school work). The mean differences with regard to children with a different actual asthma status (symptom analysis), as reported by both informants, did not differ. Compared to the child-version, the parent-version showed greater ability to detect changes in children's quality of life over time for all but one dimension, indicating better responsiveness. The results indicate that in discriminative studies child and parents reports can be substituted on a group-level. In longitudinal studies data have to be obtained from parents. Consequently, caregivers collecting quality of life data for longitudinal purposes in daily practice should collect these data simply from parents.

Asthma↗

PubMed1989

Satisfaction with social support and depressive symptoms: a panel analysis.

The literature suggests that persons who are dissatisfied with the amount of social support that has been provided to them may subsequently suffer from psychological disorder. At the same time, there is evidence that individuals who initially suffer from emotional disorder may consequently be less satisfied with their social support systems than may persons who enjoy better mental health. The purpose of this study was to test these competing hypotheses with panel data from a community survey of older adults. The findings indicate that changes in satisfaction with support tend to precede changes in depressive symptoms. A number of issues in the analysis of longitudinal data are discussed.

Adaptation, Psychological↗

PubMed2000

Dimensions of care for dementia sufferers in long-term care institutions: are they related to outcomes?

OBJECTIVES: This study empirically examined whether dimensions of care cluster in special care units (SCUs) compared with non-SCUs. The relationship between SCU status plus separate measures of the dimensions of care and outcomes for dementia sufferers was then investigated. METHODS: Data were drawn from the Intermediate Care Facility Project. The sample (N = 510) included residents with dementia, aged 65 and older, in intermediate care facilities throughout the province of British Columbia. Canada. Longitudinal data included 6 outcomes: cognitive function, behavioral problems of agitation and social skills, physical functioning, and quality of life measured through affect and expressive language skills. Separate multiple linear regression equations were estimated, relating each of these outcomes to 5 dimensions of care: preadmission and admission procedures. staff training and education, nonuse of physical and chemical restraints, flexible care routines and resident-relevant activities, and the environment. RESULTS: The results showed there is virtually no clustering of dimensions along SCU/non-SCU lines. Neither SCU status nor the individual dimensions were highly predictive of outcomes. Residents' affect at t1 emerged as a characteristic that was significantly correlated with other outcomes. DISCUSSION: This Canadian research can be added to the few but growing number of rigorous studies that suggest SCUs are not homogeneous and do not necessarily provide better care than non-SCUs. Moreover, it raises questions about the benefits of "best practice" dimensions of care, regardless of SCU status.

Aged↗

PubMed1997

Socioeconomic differences in cancer incidence and mortality.

This chapter summarizes accumulated data on the presence, magnitude and consistency of socioeconomic differentials in mortality and incidence of all malignant neoplasms and 24 individual types of neoplasms in 37 populations in 21 countries. More or less consistent excess risks in men in lower social strata were observed for all respiratory cancers (nose, larynx and lung) and cancers of the oral cavity and pharynx, oesophagus, stomach, and, with a number of exceptions, liver, as well as for all malignancies taken together. For women, low-class excesses were consistently encountered for cancers of the oesophagus, stomach, cervix uteri and, less consistently, liver. Men in higher social strata displayed excesses of colon and brain cancers and skin melanoma. In the two Latin American populations for which data were available, lung cancer was more frequent in higher social strata. Excesses in high female socioeconomic strata were seen in most populations for cancers of the colon, breast and ovary and for skin melanoma. Longitudinal data from England and Wales suggested widening over time of social class differences in men for all cancers combined and for cancers of the lung, larynx and stomach, and in women for all cancers combined and for cervical cancer.

Adolescent↗

PubMed1987

The bingo model of survivorship. V. The problems of conformation to the empirical evidence.

We discuss the statistical and biological problems of adapting the theoretical bingo model to the analysis of empirical data. A distinction is made between an idealized pathogenetic model, which aims to represent the disease in as much authentic detail as the present state of knowledge allows and in components that have literal interpretation, and an empirical model, which deals with those effects of the pathogenetic model that one may hope to observe clinically. We review a variety of empirical models distinguishable by the amount of data available on intermediate degrees of damage short of total destruction. The relationship of damage to time is explored, and we consider the criteria and usefulness of linearization of this relationship where the diachronic ("longitudinal") data are few and extend over a comparatively short time. Every time a patient is examined, the degree of cumulative damage is assessed in each of the body systems of interest. Thus the examination will furnish a set of measurements, which is obtained on each of several examinations, taken over a period that for preference is long relative to the survival of the system. Specific disorders discussed include dentition and enlargement of the aorta with age in the Marfan syndrome.

Aorta↗