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K A Olsen

Publications and source records attributed to K A Olsen.

10 recordsLinked to original sources

Prospective investigations of the prodromal state of schizophrenia: review of studies.

OBJECTIVE: The paper presents a comprehensive overview of prospective studies monitoring or intervening in the pre-onset phase of first episode psychosis. METHOD: A systematic literature search was conducted and supplemented by a manual search. All relevant studies were ordered and intensively reviewed according to specified criteria. Methodological and conceptual issues are discussed. RESULTS: Reports of 23 prospective studies were found, some describing subsamples of larger samples. Major methodological and conceptual divergences exist. CONCLUSION: Applied criteria detect individuals with a significantly increased risk of psychosis within the schizophrenia spectrum, but these criteria are only validated on clinical populations. The significance of differences in sample-characteristics is unclear. Most study samples are small. Results are preliminary and in need of further research before they constitute a realistic knowledge base. Methodological and conceptual issues should not be underestimated.

Humans↗

Prospective investigations of the prodromal state of schizophrenia: assessment instruments.

OBJECTIVE: To review assessment instruments used for detection of prodromal or at-risk mental states, and discuss their role in current research. METHOD: A systematic electronic literature search was conducted and supplemented by a manual search. All relevant scales were selected for the purpose of the review. RESULTS: Six interviews and four screening instruments were found. Two main traditions are prevailing: the Attenuated Positive Symptoms approach and the Basic Symptoms approach. Reports of psychometric properties of the interviews are preliminary. CONCLUSION: The instruments detect individuals with an increased risk of psychosis in clinical populations, but predictive validity and measures of reliability is insufficiently evaluated. Studies including instruments from both traditions should be conducted, in order to obtain an empirical basis of hypothesized relations between instruments. Instruments elucidating phenomenological aspects of anomalies in self-experience may contribute with valuable data on the pre-onset phase of psychosis.

Humans↗

Application of experimental poverty measures to the aged.

The U.S. Census Bureau recently released new, experimental measures of poverty based on a National Academy of Sciences (NAS) panel's recommendations. This article examines the effects of the experimental measures on poverty rates among persons aged 65 or older in order to help inform policy debate. Policymakers and analysts use poverty rates to measure the successes and failures of existing programs and to create and defend new policy initiatives. The Census Bureau computes the official rates of poverty using poverty thresholds and definitions of countable income that have changed little since the official poverty measure was adopted in 1965. Amid growing concerns about the adequacy of the official poverty measure, a NAS panel undertook a study of the concepts, methodology, and data needed to measure poverty. The panel concluded in its 1995 report that the current measure no longer provides an accurate picture of relative rates of poverty for different groups in the population or of changes in poverty over time. The panel recommended changes in establishing the poverty thresholds, defining family resources, and obtaining the required data. The Census Bureau report shows how estimated levels of poverty would differ from the official level as specific recommendations of the NAS panel are implemented individually and how estimated trends would differ when many recommendations are implemented simultaneously. It computes nonstandardized and standardized poverty rates. (The latter constrains the overall poverty rate under the experimental measures to match the official rate.) This article reports poverty rates that have not been standardized and provides considerably more detail than the Census report about the effects of the experimental measures on poverty among the aged. It examines the effects of changing the poverty thresholds and the items included or excluded from the definition of available resources. It also explores the effects of the experimental measures on persons aged 65 or older by age group, gender, race and ethnicity, and marital status. Results indicate that: Poverty rates in 1997 for persons aged 65 or older under the experimental NAS poverty measure are 17.3 percent, compared with 10.5 percent under the official poverty measure. This 65-percent increase is largely driven by the NAS-based measure's subtraction of medical out-of-pocket (MOOP) expenses from resources. Under the NAS-based measures, poverty rates increase for all major groups of older persons, and increase the most for groups for whom the incidence of official poverty is the lowest. The experimental NAS poverty measure shows narrower differences between genders, racial and ethnic groups, and among persons of different marital statuses than the official poverty measure. For example, white Hispanic women aged 65 or older have poverty rates that are 450 percent higher than those for white non-Hispanic men under the official poverty measure and 181 percent higher under the NAS measure. The NAS-based measure's subtraction of MOOP expenses from resources has a disproportionate effect on poverty rates among non-Hispanic whites and men as compared with other groups. However, changes in relative poverty between groups appear to be most influenced by the NAS midpoint equivalence scale. Because this scale decreases poverty rates for persons who live alone or with unrelated individuals and increases them for persons who live with others, poverty rates differ meaningfully under the NAS and official measures among demographic groups. This article highlights issues concerning the elements of the experimental NAS poverty measure that are particularly important to the measurement of poverty among the aged population. Results suggest that the research community's future efforts to refine, enhance, and build upon the NAS panel's recommendations will yield important insights about poverty among the older population.

Aged↗

Individual social security accounts: issues in assessing administrative feasibility and costs.

Whether to add individual accounts (IAs) to the Social Security system is a highly political issue. But almost lost in the debate so far have been any practical considerations about how to administer such accounts. Any discussion of whether to create individual accounts must also address the basic but critical questions of how they would work: Who would run them? What would they cost? Logistically, are they even possible? This EBRI Issue Brief provides an overview of the most salient administrative issues facing the current Social Security reform debate--issues that challenge proponents to carefully think through how their proposals could be implemented so as to achieve their policy goals. The options and difficulties in administering IAs raise concerns that cut across ideology. The object of this report is neither to dissuade the advocates nor support the critics of individual accounts. Rather, it is to bring practical considerations to a political debate that has largely ignored the pragmatic challenges of whether IAs would be too complex for participants to understand or too difficult for record keepers to administer. The major findings in this analysis include: Adding individual accounts to Social Security could be the largest undertaking in the history of the U.S. financial market, and no system to date has the capacity to administer such a system. The number of workers currently covered by Social Security--the largest single entitlement program in the nation--is at least four times higher than the combined number of all tax-favored employment-based retirement accounts in the United States, which are administered by hundreds of entities. Direct comparisons between employment-based retirement savings plans and Social Security reform are tenuous at best. Social Security covers workers and businesses that are disproportionately excluded from employment-based plans. Because of these differences, a system of individual Social Security accounts would be more difficult to administer than employment-based plans, and total administrative expenses would be larger relative to benefits. Credit-based systems such as the current Social Security program are less difficult to administer than cash-based systems, which must account for every dollar. Inherent in the "privatization" debate is generally the presumption that IA benefits would be based on cash contributions and investment returns. The current credit-based system tolerates small errors in wage reporting, because they rarely affect benefits. But every dollar counts in a cash-based IA system. To ensure that benefits are properly provided, an IA system would require more regulation, oversight, and error reconciliation than the current Social Security program. Social Security individual accounts cannot be administered like 401(k) plans without adding significant employer burdens--especially on small businesses. Under the current wage reporting and tax collection process, it would take at least 7-19 months for every dollar contributed to an individual's account to be sorted out from aggregate payments and credited to his or her IA. This 7-19 month "float period" could result in substantial benefit losses over time. Options for preventing such losses involve difficult trade-offs, such as increased government responsibility, increased complexity, greater employer burdens, and/or investment restrictions for beneficiaries. If legally considered personal property, the IAs of married participants could pose significant administrative challenges. Social Security today must obtain proof of marriage only at the time spousal benefits are claimed. But some IA proposals would require contributions to be split between spouses' individual accounts, requiring records on participants' marital status to be continuously update to ensure that contributions are correctly directed. Also, dealing with claims on individual account contributions in divorce cases could place IA record keepers in the middle o

Aged↗

Mixtures of synthetic peptides and dipalmitoylphosphatidylcholine as lung surfactants.

Synthetic peptides that differ in their lipid-peptide interactions were combined with dipalmitoylphosphatidylcholine (DPPC) and tested in an adult rat lavaged lung model in vitro for efficacy as totally synthetic lung surfactants. The putative amphipathic alpha-helical region of the major lung surfactant apoprotein (SP-A81-102), an analogue with increased amphipathic alpha-helical potential ([Lys88,97,Glu99,Trp102]-SP-A81-102]), and the hydrophobic peptide gramicidin D were all ineffective. Three water-soluble lipid-binding peptides that contain amphipathic alpha-helical regions were also tested. Of these, only a 24-residue amphipathic alpha-helical peptide (18As) based on the lipid-binding sequences of the plasma apolipoproteins was effective. Melittin and glucagon were ineffective. Mixtures of 18As and DPPC also restored gas exchange in an in vivo lavaged guinea pig lung model to 90-95% of its prelavage value and maintained it for at least 3 h. Mixtures of DPPC and 18As are also surface active (gamma min less than 4 mN/m in the pulsating bubble). These data demonstrate the efficacy of a combination of a single lipid and a small, water-soluble, nonhemolytic, synthetic peptide containing an amphipathic alpha-helical structure and a sequence unrelated to any of the reported lung surfactant apoprotein sequences.

1,2-Dipalmitoylphosphatidylcholine↗

Age-related changes in the likelihood of major contributions.

This article is concerned with the influence of age and research support on the frequency of technical innovation and economic growth. Based on the observations of Mumford and Gustafson, the authors argue that major contributions are derived from the creation of new understandings brought about by the integration and reorganization of existing understandings [1]. It is also argued that the creation of new understandings is most likely to occur in the earlier phases of people's careers when capable individuals are placed in an environment that will support innovative efforts. To examine these hypotheses and their broader economic implications, data were obtained from government sources describing the percentage of the population between the ages of twenty-five and forty-four, and between the ages of forty-five and sixty-four, as well as the percentage of the gross national product devoted to research and development efforts, the percentage of individual patents awarded, and deviations from long-term trends in the gross national product. These data were then analyzed in a time series analysis covering the period from 1929 to 1984. The results indicated that research support and age influenced the number of patents awarded which, in turn, influenced deviations in the gross national product. On the basis of these observations and the underlying theory, the authors conclude that substantially greater attention should be given to the development and maintenance of creative potential.

Adult↗

Studies on the enzymatic cleavage of norethisterone oenanthate.

Norethisterone oenanthate (NET OEN) was extensively hydrolysed in rabbit, rat and guinea pig plasma (99.9%, 76.1% and 46.0% hydrolysed in 90 min, respectively). In contrast, there was negligible hydrolysis (less than 2.5%) in dog, goat and human plasma. Rabbit liver, kidney, gut wall, stomach, heart and muscle showed marked hydrolytic activity in vitro, but there was little hydrolysis of NET OEN by either human muscle or fat. It is proposed that following intramuscular administration of NET OEN to rabbits, the ester is rapidly hydrolysed at the injection site and in the circulation whereas in humans the liver is the main site of hydrolysis since neither muscle nor plasma cause significant breakdown of the ester. The rabbit is not a good model for predicting the pharmacokinetics of NET OEN in humans.

Adipose Tissue↗

Social Security's special minimum benefit.

Social Security's special minimum primary insurance amount (PIA) provision was enacted in 1972 to increase the adequacy of benefits for regular long-term, low-earning covered workers and their dependents or survivors. At the time, Social Security also had a regular minimum benefit provision for persons with low lifetime average earnings and their families. Concerns were rising that the low lifetime average earnings of many regular minimum beneficiaries resulted from sporadic attachment to the covered workforce rather than from low wages. The special minimum benefit was seen as a way to reward regular, low-earning workers without providing the windfalls that would have resulted from raising the regular minimum benefit to a much higher level. The regular minimum benefit was subsequently eliminated for workers reaching age 62, becoming disabled, or dying after 1981. Under current law, the special minimum benefit will phase out over time, although it is not clear from the legislative history that this was Congress's explicit intent. The phaseout results from two factors: (1) special minimum benefits are paid only if they are higher than benefits payable under the regular PIA formula, and (2) the value of the regular PIA formula, which is indexed to wages before benefit eligibility, has increased faster than that of the special minimum PIA, which is indexed to inflation. Under the Social Security Trustees' 2000 intermediate assumptions, the special minimum benefit will cease to be payable to retired workers attaining eligibility in 2013 and later. Their benefits will always be larger under the regular benefit formula. As policymakers consider Social Security solvency initiatives--particularly proposals that would reduce benefits or introduce investment risk--interest may increase in restoring some type of special minimum benefit as a targeted protection for long-term low earners. Two of the three reform proposals offered by the President's Commission to Strengthen Social Security would modify and strengthen the current-law special minimum benefit. Interest in the special minimum benefit may also increase because of labor force participation and marital trends that suggest that enhancing workers' benefits may be a more effective means of reducing older women's poverty rates than enhancing spousal or widow's benefits. By understanding the Social Security program's experience with the special minimum benefit, policymakers will be able to better anticipate the effectiveness of other initiatives to enhance benefits for long-term low earners. This article presents the most recent and comprehensive information available about the special minimum benefit in order to help policymakers make informed decisions about the provision's future. Highlights of the current special minimum benefit include the following: Very few persons receive the special minimum benefit. As of December 2001, about 134,000 workers and their dependents and survivors were entitled to a benefit based on the special minimum. Of those, only about 79,000 received a higher total benefit because of the special minimum; the other 55,000 were dually entitled. (In effect, when persons are eligible for more than one type of benefit--that is, they are dually eligible--the highest benefit payable determines total benefits. If the special minimum benefit is not the highest benefit payable, it does not increase total benefits paid.) As of February 2000, retired workers who were special minimum beneficiaries with unreduced benefits and were not dually entitled were receiving, on average, a monthly benefit of $510 per month. That amount is approximately $2,000 less than the annual poverty threshold for an aged individual. Special minimum benefits provide small increases in total benefits. For special minimum beneficiaries who were not dually entitled as of December 2001, the average special minimum monthly PIA was just $39 higher than the regular PIA. Most special minimum beneficiaries are female retired workers. About 90 percent of special minimum beneficiaries are retired workers, and 77 percent of those retired workers are women. The special minimum benefit has never provided poverty-level benefits. Maximum payable special minimum benefits (unreduced for early retirement) equal 85 percent of the poverty level for aged persons, down from 96 percent at the provision's inception. Major public policy considerations raised by this analysis include the following: Social Security benefits alone do not protect all long-term low earners from poverty. Low earners with 30 years of earnings equal to the annual full-time minimum wage who retired in selected years from 1982 to 2000 received benefits that were 3.9 percent to 20.1 percent below the poverty threshold, depending on the year they retired. For 40-year earners, the range was 3.9 percent to 15.3 percent below poverty. Furthermore, in 1993, 29.2 percent of retired-worker beneficiaries who were poor had 30 or more years of coverage. The size of the universe of persistently low earners with significant attachment to the covered workforce is unknown. Available research that examines two 28-month periods suggests that only 4 percent to 6 percent of full-time, full-period earners had below-minimum wages for more than 12 consecutive months. Targeting enhanced benefits only toward long-term, regular workers who are low earners is difficult under the current Social Security program. All else being equal, if total wage-indexed lifetime covered earnings are the same for both a full-career low earner and for a high earner who has worked only occasionally, then their Social Security benefits will be identical. Social Security has no information on number of hours worked, hourly wages, or other information that could distinguish between two such persons.

Humans↗