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Background: To assess the criterion and construct validity of the KIDSCREEN-10 well-being and health-related quality of life (HRQoL) score, a short version of the KIDSCREEN-52 and KIDSCREEN-27 instruments. Methods: The child self-report and parent report versions of the KIDSCREEN-10 were tested in a sample of 22,830 European children and adolescents aged 8-18 and their parents (n = 16,237). Correlation with the KIDSCREEN-52 and associations with other generic HRQoL measures, physical and mental health, and socioeconomic status were examined. Score differences by age, gender, and country were investigated. Results: Correlations between the 10-item KIDSCREEN score and KIDSCREEN-52 scales ranged from r = 0.24 to 0.72 (r = 0.27-0.72) for the self-report version (proxy-report version). Coefficients below r = 0.5 were observed for the KIDSCREEN-52 dimensions Financial Resources and Being Bullied only. Cronbach alpha was 0.82 (0.78), test-retest reliability was ICC = 0.70 (0.67) for the self- (proxy-)report version. Correlations between other children self-completed HRQoL questionnaires and KIDSCREEN-10 ranged from r = 0.43 to r = 0.63 for the KIDSCREEN children self-report and r = 0.22-0.40 for the KIDSCREEN parent proxy report. Known group differences in HRQoL between physically/mentally healthy and ill children were observed in the KIDSCREEN-10 self and proxy scores. Associations with self-reported psychosomatic complaints were r = -0.52 (-0.36) for the KIDSCREEN-10 self-report (proxy-report). Statistically significant differences in KIDSCREEN-10 self and proxy scores were found by socioeconomic status, age, and gender. Conclusions: Our results indicate that the KIDSCREEN-10 provides a valid measure of a general HRQoL factor in children and adolescents, but the instrument does not represent well most of the single dimensions of the original KIDSCREEN-52. Test-retest reliability was slightly below a priori defined thresholds. © 2010 The Author(s).

Objective: To assess the construct and criterion validity of the KIDSCREEN-27 health-related quality of life (HRQoL) questionnaire, a shorter version of the KIDSCREEN-52. Methods: The five-dimensional KIDSCREEN-27 was tested in a sample of 22,827. For criterion validity the correlation with and the percentage explained variance of the scores of the KIDSCREEN-52 instrument were examined. Construct validity was assessed by testing a priori expected associations with other generic HRQoL measures (YQOL-S, PedsQL, CHIP), indicators of physical and mental health, and socioeconomic status. Age and gender differences were investigated. Results: Correlation with corresponding scales of the KIDSCREEN-52 ranged from r = 0.63 to r = 0.96, and r2 ranged from 0.39 to 0.92. Correlations between other HRQoL questionnaires and KIDSCREEN-27 dimensions were moderate to high for those assessing similar constructs (r = 0.36 to 0.63). Statistically significant and sizeable differences between physically and mentally healthy and ill children were found in all KIDSCREEN-27 dimensions together with strong associations with psychosomatic complaints (r = -0.52). Most of the KIDSCREEN-27 dimensions showed a gradient according to socio-economic status, age and gender. Conclusions: The KIDSCREEN-27 seems to be a valid measure of HRQoL in children and adolescents. Further research is needed to assess longitudinal validity and sensitivity to change. © 2007 Springer Science+Business Media B.V.

Objectives - To study the age of the start of the fall (critical age) in fecundity; the probability of a pregnancy leading to a healthy baby taking into account the age of the woman; and, combining these results, to determine the age dependent probability of getting a healthy baby. Design - Cohort study of all women who had entered a donor insemination programme. Setting - Two fertility clinics serving a large part of The Netherlands. Subjects - Of 1637 women attending for artificial insemination 751 fulfilled the selection criteria, being married to an azoospermic husband and nulliparous and never having received donor insemination before. Main ontcome measures - The number of cycles before pregnancy (a positive pregnancy test result) or stopping treatment; and result of the pregnancy (successful outcome). Results - Of the 751 women, 555 became pregnant and 461 had healthy babies. The fall in fecundity was estimated to start at around 31 years (critical age); after 12 cycles the probability of pregnancy in a woman aged >31 was 0.54 compared with 0.74 in a woman aged 20-31. After 24 cycles this difference had decreased (probability of conception 0.75 in women >31 and 0.85 in women 20-31). The probability of having a healthy baby also decreased - by 3.5% a year after the age of 30. Combining both these age effects, the chance of a woman aged 35 having a healthy baby was about half that of a woman aged 25. Conclusion - After the age of 31 the probability of conception falls rapidly, but this can be partly compensated for by continuing insemination for more cycles. In addition, the probability of an adverse pregnancy outcome starts to increase at about the same age. This study examined the age of the start of the fall (critical age) in fecundity, the probability of a pregnancy leading to a healthy baby taking into account the age of the women, and, by combining all of the results, the determination of the age-dependent probability of getting a healthy baby. 2 fertility clinics serving a large part of the Netherlands provided the 751 women who fulfilled the selection criteria. In this cohort study of all women who entered a donor insemination program, those who fulfilled the selection criteria were married to azoospermic husbands, were nulliparous, and never received donor insemination previously. Main outcome measures studied were the number of cycles prior to a pregnancy (positive pregnancy result) or the cessation of treatment and the result of the pregnancy (successful outcome). Of 751 women, 555 became pregnant and 461 had healthy babies. The drop in fecundity was estimated to begin at around age 31 (critical age); after 12 cycles, the probability of pregnancy in a woman age 31 was 0.54 compared with 0.74 in a woman age 20-31. After 24 cycles, this difference had decreased (probability of conception 0.75 in women 31 and 0.85 in women age 20-31). The probability of having a healthy baby also decreased, by 3.5% a year after the age of 30. Combining both of these age effects, the chance of a woman age 35 having a healthy baby was about 1.2 that of a woman age 25. After the age of 31, the probability of conception falls rapidly; however, this can be compensated for partly by continuing insemination for more cycles. In addition, the probability of an adverse pregnancy outcome begins to increase at about the same age.

Objective: This study assesses the reliability and validity of the European KIDSCREEN-52 generic health-related quality of life (HRQoL) questionnaire for children and adolescents. Research Design: The KIDSCREEN-52, which measures HRQoL in 10 dimensions, was administered to a representative sample of 22,827 children and adolescents (8 to 18 years) in 13 European countries. Psychometric properties were assessed using the Classical Test Theory approach, Rasch analysis, and structural equation modeling (SEM). A priori expected associations between KIDSCREEN scales and sociodemographic and health-related factors were examined. Test-retest reliability was assessed in 10 countries. Results: For the overall sample, Cronbach's alpha values ranged from 0.77 to 0.89. Scaling success (Multitrait Analysis Program) was >97.8% for all dimensions and Rasch analysis item fit (INFITmsq) ranged from 0.80 to 1.27. The intraclass correlation coefficients ranged from 0.56 to 0.77. No sizeable differential item functioning (DIF) was found by age, sex or health status. Four items showed DIF across countries. The specified SEM fitted the data well (root mean square error of approximation: 0.06, comparative fit index: 0.98). Correlation coefficients between Pediatric Quality of Life Inventory, Child Health and Illness Profile-Adolescent Edition, and Youth Quality of Life Instrument scales and KIDSCREEN dimensions assessing similar constructs were moderate for those (r = 0.44 to 0.61). Statistically significant differences between children with and without physical and mental health problems (Children with Special Health Care Needs screener: d = 0.17 to 0.42, Strengths and Difficulties Questionnaire: d = 0.32 to 0.72) were found in all dimensions. All dimensions showed a gradient according to socioeconomic status. Conclusions: The KIDSCREEN-52 questionnaire has acceptable levels of reliability and validity. Further work is needed to assess longitudinal validity and sensitivity to change. © 2007, International Society for Pharmacoeconomics and Outcomes Research (ISPOR).

Objectives: Orlistat, a potent and selective inhibitor of gastrointestinal lipases, is designed for the treatment of obesity. A double-blind, randomised, placebo-controlled, 2-way crossover study investigated the possible influence of orlistat on the ovulation-suppressing action of combination oral contraceptives (OC). Methods: After an 8-day run-in prior to the first of two consecutive menstrual cycles (Day 1 was the first day of menstruation), two groups of 10 healthy women, 20-27 years of age and on a stable regimen with OCs, received either 120 mg orlistat t.i.d. or placebo t.i.d, on Days 1-23 of the first cycle, and, separated by a placebo washout period on Days 24-28, the alternative treatment on Days 1-23 of the second cycle. In both cycles, serum luteinizing hormone (LH) was measured on Days 12-16 and progesterone on Days 12, 16, 19-23. Results: The geometric means of time-averaged concentrations (Days 12-16 for LH and Days 19-23 for progesterone) in the cycles with orlistat and placebo, respectively, and the one-sided 95% confidence region for the mean in the cycle with orlistat were 1.92, 2.03 and <2.23 IU l-1 for LH and 0.147, 0.145 and < 0.176 μg l-1 for progesterone. The one-sided 95% confidence region for the ratio (orlistat/placebo) of geometric means was < 1.06 for LH and < 1.11 for progesterone. Conclusion: During normal ovulation the peak serum concentration of LH is above 30 IU l-1 around Day 14 of the cycle, and that of progesterone exceeds 3 μg l-1 around day 21. The 95% confidence regions for the means, as well as all individual concentrations, were below these limits. It was concluded that orlistat did not influence the ovulation suppressing action of oral contraceptives. In the Netherlands, a double-blind, randomized, placebo-controlled, two-way crossover study was conducted to determine whether administration of the inhibitor of gastrointestinal lipases, Orlistat, concomitantly with combined oral contraceptives (OCs) inhibits the ovulation-suppressing action of OCs. The 20 subjects, 20-27 years old, were healthy and had a body mass index between 22 and 27 kg m-2. All subjects completed the study. Most adverse events were mild and related to the pharmacological effect of Orlistat (fatty or oily stool, flatus with discharge, or abdominal pain). The geometric means of time-averaged serum concentrations in the cycles with Orlistat and the placebo and the 1-sided 95% confidence region for the mean in the cycle with Orlistat were 0.147, 0.145, and less than 0.176 mcg l-1 for progesterone and 1.92, 2.03, and less than 2.23 IU l-1 for luteinizing hormone (LH), respectively. These figures were well below the peak concentrations during normal ovulation (3 mcg l-1 for progesterone and 30 IU l-1 for LH). The plasma concentration of Orlistat was either close to the limit of quantification (1 mcg l-1) or below this limit. These findings suggest that Orlistat had no effect on the ovulation-suppression capabilities of the OCs. Chemicals/CAS: Contraceptives, Oral, Combined; Enzyme Inhibitors; Lactones; Luteinizing Hormone, 9002-67-9; orlistat, 96829-58-2; Progesterone, 57-83-0

Combined oral contraceptives show clear differences in effect on the tissue factor-initiated coagulation test of activated protein C resistance, which is dependent on the presence and dosage of levonorgestrel. Multiphasic levonorgestrol oral contraceptives differ from monophasic contraceptives and resemble third-generation contraceptives. The significance of levonorgestrel dose in oral contraceptives for effects on coagulation is presented. A study in Germany was conducted to test the activated protein C resistance and assess the differences induced by various combined oral contraceptives (COCs). A resistance to activated protein C of monophasic COCs with desogestrel, gestodene, or norgestimate close to the value of women heterozygous for factor V Leiden was confirmed. Higher concentrations of levonorgestrel counteract the increase in resistance. Thus, monophasic and multiphasic COCs with levonogestrel were distinguished according to their effects on tissue-factor-initiated resistance to activated protein C. A more detailed comparison of in-vitro coagulation effects and epidemiology will further assess the plausibility and mechanisms of resistance in relation to activated protein C acquired by COC use and venous thromboembolism. Chemicals/CAS: Contraceptives, Oral, Combined; Contraceptives, Oral, Synthetic; Levonorgestrel, 797-63-7