The Flynn effect and family structure : an empirical study of the relation between changes in family structure and the development of the Flynn effect in Norway, 1969-2003

The current master thesis investigates potential causal explanations related to family structure behind what is now known as the Flynn effect. This refers to an increase in the average ability level in a given population over generations. Whereas several large-scale studies have established the relationship between a subject s ability level and this person s rank in the birth order as well as size of the sibship, changes in these effects could possibly have influenced the Flynn effect. Earlier born persons and those of smaller sibships in general obtain higher IQ scores than later borns and those of larger sibships. Hence, the assumption that changes in these effects related to family structure could have brought forth the increments of the Flynn effect was investigated. Further, the result of changes in the population ratios was also explored, whereas a shift from larger towards smaller families theoretically would yield higher IQ scores. This study is based on data obtained from two different sources. Data on ability scores stem from the psychological ability tests which the Norwegian Armed Forces administers as a part of the draft board assessment of Norwegian conscripts. These have been obtained from sesjonsdatabanken via Vernepliktsverket. This data material contains a General Ability score (made up three subtest scores) for the majority of Norwegian conscripts tested in the draft cohorts from 1969 through 2003. Additionally, data describing the family background of the subjects (rank in the birth order and sibship size) have been obtained from Statistics Norway, enabling an investigation of the relation between family structure and ability level. Analyses established changes in demography as an explanatory factor influencing the Flynn effect, as it was found to account for one fourth of the total IQ score gains in Norway in the relevant period. This signalizes the importance of investigating the developmental changes in population ratios to achieve a better understanding of the secular gains of the Flynn effect. No significant change could however be detected as a function of the birth order effect or the effects of sibship size relevant to the development of the Flynn effect. Whereas all sibships and all birth ranks increased with relative uniformity the influential source was assumed to operate at society level rather than at family level

Måleegenskaper ved den norske versjonen av Kartlegging av traumatiske erfaringer (KATES-Barn)

Beskrivelse. Kartlegging av traumeerfaringer og symptomer (KATES Barn) er et screeninginstrument for barn i alderen 7–17 år som gir foreløpig informasjon om mulig posttraumatisk stress. KATES Barn kommer i to deler; del 1 fanger opp traumatiske hendelser, og del 2 måler symptomer på posttraumatisk stress. Del 2 er delt opp i fire symptomkategorier tilpasset de diagnostiske endringene av traumediagnosen i DSM-5. KATES Barn er utviklet og validert av Sachser et al. (2017). Nasjonalt Kunnskapssenter om Vold og Traumatisk Stress var involvert i utviklingen av skalaen og ansvarlig for den norske oversettelsen. Litteratursøk. Litteratursøket resulterte i en norsk artikkel og en svensk hovedoppgave som inneholdt relevant psykometrisk informasjon og ga grunnlag for vurderingen. Psykometri. Resultatene tyder på tilstrekkelig/god indre konsistens for de fire skalaene. I det svenske utvalget fant man også tilstrekkelig test-retest-reliabilitet for totalskåren. Konfirmerende faktoranalyse på et blandet utvalg med barn fra Norge, USA og Tyskland viste at faktorstrukturen var i henhold til DSM-5s firefaktorteori for posttraumatisk stresslidelse (PTSD). Det ble også funnet støtte for konvergent validitet, og for konstruktvaliditet. De svenske normene gir begrenset informasjon om alder og geografi, og norske normer for testen mangler. Konklusjon. Dokumentasjonsgrunnlaget er ikke tilstrekkelig til å konkludere sikkert om de psykometriske egenskapene til KATES Barn. Det trengs flere studier på skandinaviske utvalg, ikke minst normdata. Testen må derfor brukes med forsiktighet i Norge

Psychological distress in spouses of somatically Ill: longitudinal findings from The Nord-Trøndelag Health Study (HUNT)

Background Studies of caregiver burden and somatic illness tend to be based on relatively small, clinical samples. Longitudinal, population based studies on this topic are still scarce and little is known about the long-term impact of partner illness on spousal mental health in the general population. In this study we investigate whether spouses of partners who either have become somatically ill or cured from illness in an 11 year period - or who have long-term illness - have different mental health scores compared to spouses of healthy partners. Methods Approximately 9000 couples with valid self-report data on a Global Mental Health (GMH) scale and somatic illness status were identified. The diagnoses stroke, angina pectoris, myocardial infarction and severe physical disability, were transformed into a dichotomous ‘any illness’-scale, and also investigated separately. Analyses of variance (ANOVA) stratified by sex were conducted with spousal GMH score at follow-up (1995–97, T2) as the outcome variable, adjusting for spousal GMH score at baseline (1984–86, T1) and several covariates. Results Results showed that male and female spouses whose partners had become somatically ill since T1 had significantly poorer mental health than partners in the reference category, comprising couples healthy at both time points. Further, female spouses of partners who had recovered from illness since T1 had significantly better mental health than controls. Of the somatic conditions, physical disability had the most significant contribution on spousal GMH, for both sexes, in addition to stroke on male spouses’ GMH. The effect sizes were small. Some of the loss of spousal mental health seems to be mediated by the ill persons’ psychological distress. Conclusion The occurrence of partner illness during the follow-up period affect the mental health of spouses negatively, while partner recovery appeared to be associated with improved mental health scores for female spouses. Of the measured conditions, physical disability had the largest impact on spousal distress, but for some conditions the distress of the ill person mediated much of the loss of mental health among spouses

Måleegenskaper ved den norske versjonen av KATES omsorgsgiver: Kartlegging av traumeerfaringer og posttraumatiske symptomer (KATES Omsorgsgiver)

publishedVersio

Preventing bias from selective non-response in population-based survey studies: findings from a Monte Carlo simulation study

Background Health researchers often use survey studies to examine associations between risk factors at one time point and health outcomes later in life. Previous studies have shown that missing not at random (MNAR) may produce biased estimates in such studies. Medical researchers typically do not employ statistical methods for treating MNAR. Hence, there is a need to increase knowledge about how to prevent occurrence of such bias in the first place. Methods Monte Carlo simulations were used to examine the degree to which selective non-response leads to biased estimates of associations between risk factors and health outcomes when persons with the highest levels of health problems are under-represented or totally missing from the sample. This was examined under different response rates and different degrees of dependency between non-response and study variables. Results Response rate per se had little effect on bias. When extreme values on the health outcome were completely missing, rather than under-represented, results were heavily biased even at a 70% response rate. In most situations, 50–100% of this bias could be prevented by including some persons with extreme scores on the health outcome in the sample, even when these persons were under-represented. When some extreme scores were present, estimates of associations were unbiased in several situations, only mildly biased in other situations, and became biased only when non-response was related to both risk factor and health outcome to substantial degrees. Conclusions The potential for preventing bias by including some extreme scorers in the sample is high (50–100% in many scenarios). Estimates may then be relatively unbiased in many situations, also at low response rates. Hence, researchers should prioritize to spend their resources on recruiting and retaining at least some individuals with extreme levels of health problems, rather than to obtain very high response rates from people who typically respond to survey studies. This may contribute to preventing bias due to selective non-response in longitudinal studies of risk factors and health outcomes