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PubMed1995

Migration and social change: a longitudinal study of the social mobility of 'immigrants' in England and Wales.

"Data from the OPCS Longitudinal Study is used to examine the social mobility of 'immigrants' in England and Wales between 1971 and 1981. Three issues are raised: (i) in what respects and to what degree do 'immigrants' differ in their social mobility characteristics from the norm set by the population as a whole?; (ii) in what respects and to what degree do 'immigrants' differ amongst themselves in their social mobility characteristics according to their country of origin?; and (iii) how do 'second-generation immigrants' and recently-arrived immigrants differ in their social class locations from those who have been in the British labour market for a considerable length of time?" (SUMMARY IN FRE)

Demography↗
PubMed2002

Statistical techniques for the analysis of change in longitudinal studies of the menopause.

OBJECTIVE: Critical review of statistical techniques used to analyze data from longitudinal studies. METHOD: Literature search and classification of statistical methods and their utilization evaluated against known underlying assumptions. RESULTS: One hundred and twenty-three papers found: 1. cross-sectional reduction of data (56%); 2. multifactorial techniques (26%); 3. repeated measurement analysis of variance (14%); 4. other (time series and structural equation modelling) (4%). CONCLUSIONS: Cross-sectional reduction violates underlying statistical assumptions. A simple and powerful technique is to mean values prior to and following an event such as the final menstrual period. To allow for the influence of multiple factors, linear regression is preferred to logistic regression where continuous data are available. For more information about evolution in time, more complex techniques are needed. A suitable technique is repeated measurement multivariate analysis of variance using a number of contrasts to estimate various effects. Split plot or randomized block designs cannot be recommended as they violate compound symmetry assumptions. For series involving more than 100 observations for each subject, time series and spectral analysis techniques should be considered. Structural equation modelling is recommended for examination in detail of a range of factors that may influence the studied end-point, the presence of feedback and of latent or non-measurable variables.

Adult↗
PubMed1997

Negative life events, marital interaction, and the longitudinal course of newlywed marriage.

Life events and problem-solving behavior were examined relative to longitudinal change in depressive symptoms and marital adjustment over 18 months in 60 newlywed couples. Spouses' problem-solving behavior moderated, but did not mediate, the relationship between life events and adjustment. Some behaviors contributed to spouses being more resilient to life events, and some behaviors made spouses more vulnerable. In particular, wives' anger facilitated their adjustment to major and interpersonal events such that their depressive symptoms declined and their marital satisfaction increased. Husbands' humor contributed to marital instability when spouses reported more major events. The results further specify the vulnerability-stress-adaptation model of marriage and expand on the role of behavior in marriage.

Adult↗
PubMed1994

Volumetric magnetic resonance imaging quantification of longitudinal brain changes in abstinent alcoholics.

Magnetic resonance imaging (MRI) of the brain was performed on a group of 24 recently detoxified, male alcoholics approximately 1 month after their date of last drink. The imaging was repeated 3 months later, at which point 9 subjects had resumed drinking and 15 had maintained abstinence. Contrasts between these two drinking groups revealed that, despite comparable baseline values, the Abstainers exhibited volumetric white matter increases and cerebrospinal fluid reductions over the follow-up interval, whereas the Drinkers did not show significant change on either of these MRI indices. These results provide the first evidence suggestive of significant volumetric white matter increase with abstinence.

Adult↗
PubMed1997

Reproducibility of TMR for the determination of longitudinal mineral changes in dental hard tissues.

Transverse microradiography (TMR) of thin sections is the principal method for determining mineral changes in experimental lesions. Because it has become also the standard by which newly-developed methods are validated, demands on all steps of the procedure are high. Thin sections of enamel and dentin require high-precision cutting or lapping to preserve surface structures, but their different brittleness and elasticity preclude a uniform procedure. Image analysis permits the measurement of fine details at a micron scale, but because most studies are aimed at overall mineral changes, they are usually lost on broadening of the scan areas and averaging of experimental groups. Small errors in repositioning of the scan areas for repetitive measurements may yield distorted lesion profiles, while quantitative data such as the integrated mineral loss are hardly influenced. A major reason for "irreproducibility" of TMR are the different definitions of the lesion parameters as used by various research groups. We recommend that these definitions be agreed on if the full potential of TMR as an international standard is to be utilized.

Absorptiometry, Photon↗
PubMed2001

Explaining adolescent exercise behavior change: a longitudinal application of the transtheoretical model.

The developmental decline and benefits of exercise are documented, however, relatively little is known about the mechanisms and motivations underlying adolescent exercise behavior This project investigates which variables drive exercise or are a consequence thereof, within the Transtheoretical Model (TTM). Baseline questionnaires (N = 819) were collected through 5 Canadian high schools. For this longitudinal investigation, all baseline participants were approached for a 3-year follow up. Follow-up questionnaire completers (n = 400: mean baseline age = 14.89, SD = 1.15, mean follow-up age = 17.62 years, SD = 1.18) were not different from noncompleters (n = 419) on all baseline variables, except for sex (54. 75% and 43. 68% females, respectively; p <. 003). Stages, processes, self-efficacy, pros and cons of exercise from the TTM, and self-reported exercise were assessed. Panel analyses revealed that although the directions of the relations were as hypothesized, the processes did not significantly lead to exercise or vice versa. As hypothesized, exercise leads to self-efficacy and pros and cons, showing that the TTM can serve as a framework to understand adolescent exercise behavior Future research needs to incorporate shorter assessment intervals and use larger samples to be able to look at adjacent stage transitions.

Adolescent↗
PubMed2002

[Compliance variation following the change of longitudinal stretch ratio. A study on femoral artery and vein in a rabbit model].

This study was aimed to establish a rabbit model of bridging artery defect with autogenous vein under equal arterial and venous compliances by selecting an appropriate anastomosing tension based on assessing the influence of vessel's longitudinal strain on compliance. The exponential form P = M1 x [eM2(v-v0)-1] was employed to fit the blood pressure-unit volume curves under different stretch ratios(lambda) obtained from real curves on 13 femoral arteries and 12 veins whose uniaxial loading tests at longitudinal directions had been performed, then the quantic M = a1 lambda 5 + a2 lambda 4 + a3 lambda 3 + a lambda 2 + a5 lambda + a6 was done to fit M-lambda data. Results showed the differential form dv/dp = 1/(M1 x M2 + 11.78 M2) derived from P = M1 x [eM2(v-v0)-1], and lambda reflected the relationship between compliance and stretch ratio (or longitudinal tension) under average artery pressure 11.78 KPa well. It was found that under longitudinal tension 1.19 g, the arterial and venous compliances were equal(0.031 microliter/KPa) while the respective stretch ratios were 1.32 and 1.67.

Animals↗
PubMed1979

Obstruction induced changes in longitudinal force-length relations of rabbit ureter.

The force-length relationships of rabbit ureters subjected to 2 weeks of obstruction were compared with those of normal rabbit ureters. After 2 weeks of ureteral obstruction, length increased by 24 per cent, diameter by 100 per cent, and cross-sectional muscle area by 248 per cent. At the in vivo length, the resting forces of the control and obstructed ureters were similar. With muscle lengthening, resting force increased. For the same per cent increase over in vivo length, both control and obstructed ureters exhibited the same resting forces. At the in vivo length, the obstructed ureter developed less active force and less stress in response to a suprathreshold electrical stimulus than did control ureters. At the length of maximum force development (1.4 times the in vivo length for both control and obstructed ureters), the force developed by the obstructed ureter was 3.5 times greater than that of the control, yielding a 250 per cent increase over control levels. Thus, active stress (force/unit area) was unchanged after 2 weeks of obstruction.

Animals↗
PubMed2006

The relationship of perfectionism, depression, and therapeutic alliance during treatment for depression: latent difference score analysis.

The authors examined the longitudinal relationship of patient-rated perfectionism, clinician-rated depression, and observer-rated therapeutic alliance using the latent difference score (LDS) analytic framework. Outpatients involved in the Treatment for Depression Collaborative Research Program completed measures of perfectionism and depression at 5 occasions throughout treatment, with therapeutic alliance measured early in therapy. First, LDS analyses of perfectionism and depression established longitudinal change models. Further LDS analyses revealed significant longitudinal interrelationships, in which perfectionism predicted the subsequent rate of depression change, consistent with a personality vulnerability model of depression. In the final LDS model, the strength of the therapeutic alliance significantly predicted longitudinal perfectionism change, and perfectionism significantly predicted the rate of depression change throughout therapy. These results clarify the patterns of growth and change for these indicators throughout depression treatment, demonstrating an alternative method for evaluating longitudinal dynamics in therapy.

Adult↗
PubMed2006

Measuring longitudinal white matter changes: comparison of a visual rating scale with a volumetric measurement.

BACKGROUND AND PURPOSE: Detection of longitudinal changes in white matter hyperintensities (WMH) by using visual rating scales is problematic. We compared a widely used visual rating scale with a volumetric method to study longitudinal white matter changes. METHODS: WMH were assessed with the visual Scheltens scale and a volumetric method in 100 elderly subjects aged 70-81 years for whom repetitive MR images were available with an interval of 33 (SD, 1.4) months. Reliability was determined by intraclass correlation coefficients. To examine the sensitivity of both the visual and volumetric method, we calculated Spearman rank correlations of WMH ratings and volume measurements with age. RESULTS: Reliability of the visual rating scale was good, whereas reliability of the volumetric measurement was excellent. For baseline measurements of WMH, we found weaker associations between WMH and age when assessed with the visual scale (r = 0.20, P = .045) than with the volumetric method (r = 0.31, P = .002). Longitudinal evaluation of WMH assessments showed regression in 26% of the subjects when analyzed with the visual rating scale against 12% of the subjects when using volumetric measurements. Compared with the visual rating, the correlation between progression in WMH and age was twice as high when using the volumetric measurement (r = 0.19, P = .062 and r = 0.39, P < .001, respectively). CONCLUSION: Volumetric measurements of WMH offer a more reliable, sensitive, and objective alternative to visual rating scales in studying longitudinal white matter changes.

Aged↗
PubMed2000

Husbands caring for wives with dementia: a longitudinal study of continuity and change.

The longitudinal study reported in this article examines how the patterns of change over time for husbands who continue to care for their spouses in the community compare with husbands who place their spouses in nursing homes. There were 74 older men enrolled in the study initially; follow-up interviews were conducted with the available husbands who continued to provide care in their own homes or who had placed their spouses in nursing homes after one year. Potential theoretical relevance of the current findings and their implications for health and mental health social workers in terms of assessment, treatment, and program development for older male caregivers is highlighted.

Adaptation, Psychological↗
PubMed2003

Soluble E-selectin, soluble L-selectin and soluble ICAM-1 in bronchopulmonary dysplasia, and changes with dexamethasone.

OBJECTIVE: To evaluate longitudinal change in arterial blood plasma levels of soluble adhesion molecules in infants of <30 weeks' gestation with respiratory distress syndrome (RDS) and to look for differences in these levels in neonates who subsequently developed bronchopulmonary dysplasia (BPD) compared with those neonates who did not, and also to investigate the effect of dexamethasone treatment on levels of soluble adhesion molecules in plasma. METHODS: We measured plasma concentrations of soluble L-selectin (sL-selectin), soluble E-selectin (sE-selectin), and soluble intercellular adhesion molecule-1 on days 1, 3, 7, 14, 21, and 28 of life and before and 2 to 3 days after initiating a 6-day course of dexamethasone treatment. Infants with RDS were followed until discharge and were classified as non-BPD and either 1) BPD day 28 reflecting oxygen requirement on day 28 but not at 36 corrected weeks or 2) BPD 36 weeks reflecting oxygen requirement at 36 (corrected) weeks' gestation. The classification of presence or absence of BPD by oxygen requirement was supported by and was consistent with radiologic findings of BPD for all infants. The difference between BPD day 28 and BPD 36 weeks was supported by more extensive radiologic effects in the latter. RESULTS: The arterial plasma level of sL-selectin in infants who had RDS and did not develop BPD was significantly decreased compared with term healthy infants, as was the level of sE-selectin. Compared with infants who had RDS and did not develop BPD, sL-selectin levels were even further decreased in infants who had RDS and did develop BPD both at birth and throughout the first 4 weeks of life (day 1 through day 28). Infants with BPD also showed increasing levels of sE-selectin during this period of time, whereas infants without BPD did not. Levels of soluble intercellular adhesion molecule-1 in infants without BPD were not different from infants with BPD initially but increased in infants with BPD compared with infants without BPD, significant on day 28 in both groups. Dexamethasone treatment increased concentration of sL-selectin and decreased concentration of sE-selectin. CONCLUSIONS: Low sL-selectin may be an early indicator of enhanced risk for BPD. Low levels of sL-selectin and increasing levels of sE-selectin may be risk factors for BPD. The effects of dexamethasone treatment include significant modulation of adhesion molecules.

Adult↗
PubMed1994

Ten-year change in the use of medical drugs among the elderly--a longitudinal study and cohort comparison.

Longitudinal changes and cohort differences from 1979 to 1989 in the use of prescribed and non-prescribed medical drugs were examined and the connections of drug use to various background variables were analysed in the framework of the Tampere Longitudinal Study of Ageing. In the longitudinal study random samples of men and women born in 1900-09 and 1910-19 (738 persons) were interviewed in 1979 and the survivors (62%) were interviewed again in 1989. In the cohort comparison the 60-69-year-olds studied in 1979 (364 persons) were compared with the 60-69-year-olds in 1989 (395 persons). In the longitudinal setting the number of prescribed drugs increased. In 1989 2 or 3 in 10 persons used at least five prescribed drugs simultaneously. In the cohort comparison there were no differences in the number of prescribed drugs between the two groups of 60-69-year-olds. Use was connected with multimorbidity and poor self-rated health. Both the longitudinal comparison in the group born in 1910-19 and the cohort comparison revealed a significant increase in the use of non-prescribed drugs. The use of analgesics was connected with sex, occupational class, self-rated health and feelings of loneliness. In the use of vitamins, no connection was found with health variables, but they were mostly used by white-collar employees and women. However, when all these variables were controlled for, both analgesics and, in particular, vitamins were used more in 1989 than in 1979. The results suggest that the increase in the use of non-prescribed drugs is mainly due to social and historical factors, by changes both in drug policies, health culture and health behaviour of elderly persons.

Age Factors↗