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1.
Ultrasound Obstet Gynecol ; 57(3): 431-439, 2021 03.
Article in English | MEDLINE | ID: mdl-32959909

ABSTRACT

OBJECTIVE: To evaluate the long-term outcomes of children born to women with a short cervix and otherwise low risk for preterm birth, after antenatal exposure to vaginal progesterone vs placebo. METHODS: This was a follow-up study of the Triple P trial, which randomized 80 low-risk women with a short cervix (≤ 30 mm) at 18-22 weeks' gestation to progesterone (n = 41) or placebo (n = 39). At 2 years of corrected age, children were invited for a neurodevelopmental assessment, using the Bayley Scales of Infant and Toddler Development, third edition (BSID-III), and a neurological and physical examination by an assessor blinded to the allocated treatment. Parents filled out the Ages and Stages Questionnaire, the Child Behavior Checklist (CBCL) and a general-health questionnaire. The main outcome of interest was mean BSID-III cognitive and motor scores. Additionally, a composite score of mortality and abnormal developmental outcome, including BSID-III ≤-1 SD, CBCL score in the clinical range and/or parental reported physical problems (at least two operations or at least two hospital admissions in the previous 2 years), was evaluated. Our sample size, dictated by the original sample of the Triple P trial, provided 80% power to detect a mean difference (MD) of 15 points (1 SD) between groups for the BSID-III tests. RESULTS: Of the 80 children born to the randomized women, one in the progesterone group and two in the placebo group died in the neonatal period. Follow-up data were obtained for 59/77 (77%) children and BSID-III outcomes in 57 children (n = 28 in the progesterone group and n = 29 in the placebo group) born at a median gestational age of 38 + 6 weeks (interquartile range (IQR), 37 + 3 to 40 + 1 weeks) with a median birth weight of 3240 g (IQR, 2785-3620 g). In the progesterone vs placebo groups, mean BSID-III cognitive development scores were 101.6 vs 105.0 (MD, -3.4 (95% CI, -9.3 to 2.6); P = 0.29) while mean motor scores were 102.4 vs 107.3 (MD, -4.9 (95% CI, -11.2 to 1.4); P = 0.13). No differences were seen between the two groups in physical (including genital and neurological examination), behavioral and health-related outcomes. CONCLUSION: In this sample of children born to low-risk women with a short cervix at screening, no relevant differences in neurodevelopmental, behavioral, health-related and physical outcomes were found between offspring exposed to vaginal progesterone and those exposed to placebo. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Neurodevelopmental Disorders/epidemiology , Premature Birth/prevention & control , Prenatal Exposure Delayed Effects/epidemiology , Progesterone/adverse effects , Progestins/adverse effects , Administration, Intravaginal , Adult , Cervical Length Measurement , Cervix Uteri/pathology , Child Development/drug effects , Child, Preschool , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Male , Mental Status and Dementia Tests , Neurodevelopmental Disorders/chemically induced , Pregnancy , Premature Birth/diagnostic imaging , Prenatal Exposure Delayed Effects/chemically induced , Progesterone/administration & dosage , Progestins/administration & dosage , Treatment Outcome
2.
BMC Med Res Methodol ; 19(1): 227, 2019 12 04.
Article in English | MEDLINE | ID: mdl-31801463

ABSTRACT

BACKGROUND: Goal Attainment Scaling (GAS) is an instrument that is intended to evaluate the effect of an intervention by assessing change in daily life activities on an individual basis. However, GAS has not been validated adequately in an RCT setting. In this paper we propose a conceptual validation plan of GAS in the setting of rare disease drug trials, and describe a hypothetical trial where GAS could be validated. METHODS: We have used the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) taxonomy to deduce which measurement properties of GAS can be evaluated, and how. As individual GAS scores cannot be interpreted outside the context of a RCT, the validation of GAS needs to be done on trial as well as on individual level. RESULTS: The procedure of GAS consists of three steps. For the step of goal selection (step 1) and definition of levels of attainment (step 2), face validity may be assessed by clinical experts. For the evaluation of the goal attainment (step 3), the inter and intra rater reliability can be evaluated on an individual level. Construct validity may be evaluated by comparison with change scores on other instruments measuring in the same domain as particular goals, if available, and by testing hypotheses about differences between groups. A difference in mean GAS scores between a group who received an efficacious intervention and a control group is an indication of well-chosen goals, and corroborates construct validity of GAS on trial level. Responsiveness of GAS cannot be evaluated due to the nature of the construct being assessed. CONCLUSION: GAS may be useful as an instrument to assess functional change as an outcome measure in heterogeneous chronic rare diseases, but it can only be interpreted and validated when used in RCTs with blinded outcome assessment. This proposed theoretical validation plan can be used as a starting point to validate GAS in specific conditions.


Subject(s)
Goals , Outcome Assessment, Health Care , Rare Diseases/therapy , Activities of Daily Living , Clinical Trials as Topic , Humans , Psychometrics , Reproducibility of Results , Research Design
3.
Ultrasound Obstet Gynecol ; 51(5): 621-628, 2018 May.
Article in English | MEDLINE | ID: mdl-29468770

ABSTRACT

OBJECTIVE: A recent randomized clinical trial (ProTWIN) showed that a cervical pessary prevented preterm birth and improved neonatal outcome in women with multiple pregnancy and cervical length (CL) < 38 mm. In this follow-up study, the long-term developmental outcome of these children was evaluated at 3 years' corrected age. METHODS: This was a follow-up study of ProTWIN, a multicenter trial conducted between 2009 and 2012 in which asymptomatic women with a multiple pregnancy were randomized to placement of a cervical pessary or no intervention. Current follow-up and analysis were limited to mothers with a mid-trimester CL < 38 mm (78 women (157 children) in the pessary group and 55 women (111 children) in the control group). At 3 years of corrected age, surviving children were invited for a Bayley Scales of Infant and Toddler Development-third edition (Bayley-III) assessment. Death after randomization or neurodevelopmental disability (Bayley-III score of ≤ 85, 1 SD below mean) rates were compared between the pessary and control groups, according to the intention-to-treat principle and using multiple imputation for missing data. Mean Bayley-III scores in surviving children were also assessed. A linear mixed-effects model was used to adjust for correlation between children of one mother. RESULTS: From the time of entry in the ProTWIN trial until follow-up at 3 years of age, a total of 27 children had died (six (5%) in the pessary vs 21 (26%) in the control group; odds ratio (OR), 0.13; 95% CI, 0.04-0.48). Bayley-III outcomes were collected for 173/241 (72%) surviving children (114 (75%) in the pessary vs 59 (66%) in the control group). The cumulative incidence of death or survival with a neurodevelopmental disability was 12 (10%) in the pessary vs 23 (29%) in the control group (OR, 0.26; 95% CI, 0.09-0.73). No statistical or clinically relevant differences were found with respect to cognitive, language and motor development among surviving children between the groups. Comparable results were found after multiple imputation. CONCLUSION: In women with twin pregnancy and a CL < 38 mm, the use of a cervical pessary strongly improved survival of the children without affecting neurodevelopment at 3 years' corrected age. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Subject(s)
Neurodevelopmental Disorders/epidemiology , Pessaries , Pregnancy, Twin , Premature Birth/prevention & control , Adult , Cervical Length Measurement/statistics & numerical data , Cervix Uteri/diagnostic imaging , Child, Preschool , Female , Follow-Up Studies , Gestational Age , Humans , Infant, Newborn , Male , Neurodevelopmental Disorders/diagnosis , Neurodevelopmental Disorders/etiology , Pregnancy , Pregnancy Outcome/epidemiology , Premature Birth/epidemiology , Statistics, Nonparametric
4.
BMC Pediatr ; 18(1): 147, 2018 05 02.
Article in English | MEDLINE | ID: mdl-29720158

ABSTRACT

BACKGROUND: There is increasing evidence that neonatal seizures in term neonates with stroke, asphyxia or brain haemorrhage might be associated with adverse neurodevelopment and development of epilepsy. The extent of this association is not known. The objective of this study was to assess the possible impact of neonatal seizures on these outcomes and if possible calculate a relative risk. METHODS: A systematic review and meta-analysis was performed (study period January 2000-June 2015). PubMed, Medline and Embase were searched for cohort studies evaluating neurodevelopmental outcome at the age of at least 18 months or development of epilepsy in surviving term neonates with or without neonatal seizures. The methodological quality of included studies was assessed and data extractions were performed in a standardized manner by independent reviewers. Pooled Relative Risks (RR) with 95% confidence intervals for adverse outcome were calculated if possible. RESULTS: Out of 1443 eligible studies 48 were selected for full text reading leaving 9 cohort studies for the final analyses (4 studies on stroke, 4 on perinatal asphyxia and one on cerebral hemorrhage). For all cases with stroke or asphyxia combined the pooled risk ratio (RR) for adverse outcome when suffering neonatal seizures was 7.42 (3.84-14.34); for neonates with perinatal asphyxia: 8.41 (4.07-17.39) and for neonates with stroke: 4.95 (1.07-23.0). The pooled RR for development of late onset epilepsy could only be determined for infants suffering from stroke: 1.48 (0.82-2.68). Results were biased and evidence sparse. CONCLUSIONS: The presence of neonatal seizures in term newborns with vascular or hypoxic brain injury may have an impact on or be a predictor of neurodevelopmental outcome. The biased available data yield insufficient evidence about the true size of this association.


Subject(s)
Asphyxia Neonatorum/complications , Cerebral Hemorrhage/complications , Hypoxia, Brain/complications , Neurodevelopmental Disorders/etiology , Seizures/complications , Stroke/complications , Epilepsy/etiology , Humans , Infant, Newborn , Prognosis , Risk Factors
5.
Child Care Health Dev ; 43(3): 369-384, 2017 05.
Article in English | MEDLINE | ID: mdl-27774638

ABSTRACT

BACKGROUND: High levels of maltreatment are found in children who are identified because their parents visit the emergency department due to partner violence, substance abuse or suicide attempt. However, it is unknown if these children experience psychosocial problems. This study aims to assess their levels of post-traumatic stress, anxiety, depression, behavioural problems and health-related quality of life. METHODS: A cross-sectional study was conducted in six hospitals. All consecutive families of which a parent visited the emergency department due to partner violence, substance abuse or suicide attempt between 1 July 2012 and 1 March 2014 with children aged 1.5-17 years were approached for participation. Parents and children aged 8 years and older filled out questionnaires measuring post-traumatic stress [13-item version of Children's Revised Impact of Event Scale (CRIES-13)], anxiety, depression (Revised Child Anxiety and Depression Scale), behavioural problems [Child Behavior Checklist (CBCL) and Youth Self-Report (YSR)] and health-related quality of life (PedsQL). Scores of participants were compared with reference data obtained in children in similar age ranges from representative Dutch community samples (CRIES-13, Revised Child Anxiety and Depression Scale, PedsQL and CBCL) and to a normed cutoff score (CRIES-13). RESULTS: Of 195 eligible families, 89 (46%) participated in the study. Participating children did not score different from community children, both on child-reported and parent-reported instruments. Standardized mean differences of total sum scores were 0 (CRIES-13 and CBCL 1.5-5), 0.1 (YSR), 0.2 (CBCL 6-18) and -0.3 (PedsQL) and not statistically different from community children. Thirty-five percent of the participating children scored above the cutoff score on the CRIES-13, indicating post-traumatic stress disorder, but this difference was not statistically significant from community children (mean difference 8%; 95% CI -4-22%). CONCLUSIONS: We found no differences in psychosocial problems between children whose parents visited the emergency department due to partner violence, substance abuse or suicide attempt and children from community samples. Because 35% of the children scored in the range of post-traumatic stress disorder, we advise healthcare providers to pay attention to post-traumatic stress symptoms.


Subject(s)
Child Behavior Disorders/diagnosis , Child of Impaired Parents/psychology , Emergency Service, Hospital , Parents , Spouse Abuse/psychology , Stress Disorders, Post-Traumatic/diagnosis , Substance-Related Disorders/psychology , Suicide, Attempted/psychology , Adolescent , Affective Symptoms , Child , Child Behavior Disorders/psychology , Child, Preschool , Cross-Sectional Studies , Emergency Service, Hospital/statistics & numerical data , Female , Humans , Infant , Male , Netherlands/epidemiology , Psychiatric Status Rating Scales , Quality of Life , Surveys and Questionnaires
7.
Eur J Pediatr ; 172(8): 1105-10, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23640022

ABSTRACT

UNLABELLED: High plasma C-reactive protein (CRP) levels are associated with favorable outcome in adults with acute lung injury (ALI). The association between CRP levels and outcome has not been studied in ALI in children. We performed a historical cohort study in 93 mechanically ventilated children (0-18 years) with ALI. The CRP level within 48 h of disease onset was tested for association with 28-day mortality and ventilator-free days (VFD). Clinical parameters and ventilator settings were evaluated for possible confounding. Fourteen patients died within 28 days. The median (interquartile range) CRP level in nonsurvivors was 126 mg/L (64; 187) compared with 56 mg/L (20; 105) in survivors (p = 0.01). For every 10-mg/L rise in CRP level, the unadjusted odds (95% confidence interval (95% CI)) for mortality increased 8.7% (2.1-15.8%). Cardiovascular organ failure at onset of ALI was the strongest predictor for mortality (odds ratio, 30.5 (6.2-152.5)). After adjustment for cardiovascular organ failure, for every 10-mg/L rise in CRP level, the OR (95% CI) for mortality increased 4.7% (-2.7-12.6%; p = 0.22). Increased CRP levels were associated with a decrease in VFD (ρ = -0.26, p = 0.01). CONCLUSION: increased plasma CRP levels are not associated with favorable outcome in ALI in children. This is in contrast with findings in adults with ALI.


Subject(s)
Acute Lung Injury/blood , C-Reactive Protein/metabolism , Respiration, Artificial , Acute Lung Injury/mortality , Acute Lung Injury/therapy , Adolescent , Biomarkers/blood , Child , Child, Preschool , Cohort Studies , Female , Humans , Infant , Infant, Newborn , Intensive Care Units, Pediatric , Logistic Models , Male , Odds Ratio , Prognosis , Severity of Illness Index
8.
Neuropediatrics ; 42(1): 13-7, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21500142

ABSTRACT

Short-chain acyl-CoA dehydrogenase deficiency (SCADD) is an autosomal recessive inborn error of metabolism, most frequently associated with developmental delay and/or epilepsy. Most SCADD patients carry common SCAD-encoding gene ( ACADS) variants or these variants in combination with a rare ACADS mutation, in the Netherlands predominantly the c.1058C>T. Epilepsy in childhood often remains unexplained and patients with epilepsy related to SCADD may remain undiagnosed because studies for SCADD are often not performed. To test this hypothesis and to further estimate the extent of the Dutch SCADD population, we performed a study on blood spot samples in 131 paediatric patients with epilepsy and 909 anonymous newborns and investigated the presence of the 2 common ACADS variants and the rare c.1058C>T mutation. Overall, the 2 common ACADS variants and the rare c.1058C>T mutation were detected in either homozygous or compound heterozygous forms in 9.2% of the epilepsy and 7.5% of the reference group. A birth prevalence of SCADD with a mutation/variant genotype in the Netherlands as high as >1:1,000 was calculated. This is in contrast with the low number of patients diagnosed clinically and supports the hypothesis that SCADD is clinically irrelevant. Furthermore our study does not support an association between SCADD and epilepsy.


Subject(s)
Epilepsy/epidemiology , Lipid Metabolism, Inborn Errors/epidemiology , Acyl-CoA Dehydrogenase/deficiency , Acyl-CoA Dehydrogenase/genetics , Adolescent , Butyryl-CoA Dehydrogenase/genetics , Child , Child, Preschool , DNA Mutational Analysis , Female , Humans , Incidence , Infant , Infant, Newborn , Lipid Metabolism, Inborn Errors/diagnosis , Lipid Metabolism, Inborn Errors/genetics , Male , Mutation/genetics , Netherlands/epidemiology , Pediatrics
9.
Stat Methods Med Res ; 28(6): 1893-1910, 2019 06.
Article in English | MEDLINE | ID: mdl-29921167

ABSTRACT

Goal Attainment Scaling is an assessment instrument to evaluate interventions on the basis of individual, patient-specific goals. The attainment of these goals is mapped in a pre-specified way to attainment levels on an ordinal scale, which is common to all goals. This approach is patient-centred and allows one to integrate the outcomes of patients with very heterogeneous symptoms. The latter is of particular importance in clinical trials in rare diseases because it enables larger sample sizes by including a broader patient population. In this paper, we focus on the statistical analysis of Goal Attainment Scaling outcomes for the comparison of two treatments in randomised clinical trials. Building on a general statistical model, we investigate the properties of different hypothesis testing approaches. Additionally, we propose a latent variable approach to generate Goal Attainment Scaling data in a simulation study, to assess the impact of model parameters such as the number of goals per patient and their correlation, the choice of discretisation thresholds and the type of design (parallel group or cross-over). Based on our findings, we give recommendations for the design of clinical trials with a Goal Attainment Scaling endpoint. Furthermore, we discuss an application of Goal Attainment Scaling in a clinical trial in mastocytosis.


Subject(s)
Data Interpretation, Statistical , Endpoint Determination , Patient Care Planning , Randomized Controlled Trials as Topic/methods , Endpoint Determination/statistics & numerical data , Humans , Models, Statistical , Probability , Rare Diseases/therapy , Treatment Outcome
10.
Orphanet J Rare Dis ; 14(1): 31, 2019 02 07.
Article in English | MEDLINE | ID: mdl-30732630

ABSTRACT

BACKGROUND: Clinical trials in rare diseases are more challenging than trials in frequent diseases. Small numbers of eligible trial participants, often complicated by heterogeneity among rare disease patients, hamper the design and conduct of a 'classical' Randomized Controlled Trial. Therefore, novel designs are developed by statisticians. However, it is important to be aware of possible design aspects that may jeopardize the feasibility of trial conduct. If the burden of participation is considered out of proportion by patients or parents, recruitment may fail or participants may drop out before trial completion. In order to maximize the chance of success of trials in small populations, it is important to know which aspects of trial design are considered important by patients. RESULTS: We have interviewed all ten members of the Patient Think Tank (PTT) of the ASTERIX project, a European research consortium on methodology for clinical trials in small populations. The PTT members are rare disease patient representatives who have completed extensive training in clinical trial methodology. We have analyzed the interviews qualitatively according to Grounded Theory using a thematic analysis, and we structured the topics in four chronologically ordered themes: 1. Involvement in trial design; 2. Opinions on trial design; 3. Trial participation; 4. Phase after the trial. Our main findings are that the PTT-members recommend that patients are involved in trial design from an early stage on, and have influence on the outcomes and measurement instruments that are chosen in the trial, the length of the study, the choice of participants, and the information that is sent to potential participants. Also, according to the PTT-members, patient groups should consider setting up disease registries, placebo groups should be minimized, and more education on clinical trials is advised. CONCLUSIONS: Rare disease patient representatives who have been educated about clinical trial methodology think it is important to involve patient representatives in research at an early stage. They can be of advice in trial design in such a way that the ratio of potential benefit and burden of trial participation as well as the chosen outcome measures and in- and exclusion criteria are optimized.


Subject(s)
Qualitative Research , Rare Diseases , Humans , Patient Participation , Patient Selection , Quality of Life
11.
Neuromuscul Disord ; 18(7): 541-4, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18579378

ABSTRACT

Thirty-four children with genetically proven SMA type I (age at onset <6 months, unable to sit during study period) were included in a 3-year prospective cohort study and neurologically followed-up until death or the end of the study. At the end of the study period 31/34 children had died. The median age at death was 176 days (95% Confidence Interval 150-214 days), the median survival from the time of diagnosis was 158 days (95% CI 137-232 days). The median survival after diagnosis did not differ significantly between children diagnosed at birth (median survival 137 days, 95% CI 111-232 days) and those diagnosed later (median survival 159 days, 95% CI 141-256), implying that SMA I cases with different ages of onset show the same progression rate of the disease. The number of SMN2 copies was not clearly correlated with survival duration, possibly because of lack of statistical power due to the small number of cases with 1 or 3 SMN2 copies. The three cases alive at the end of the study had either three or an unknown number of SMN2 copies, which is in agreement with previously described cases showing longer survival with increasing number of SMN2 copies. All deceased children died of respiratory insufficiency and/or an intercurrent lung infection, indicating that the susceptibility of the child with SMA type I to respiratory infections plays an important role in determining the survival.


Subject(s)
Spinal Muscular Atrophies of Childhood/epidemiology , Spinal Muscular Atrophies of Childhood/mortality , Age of Onset , Child, Preschool , Confidence Intervals , Cyclic AMP Response Element-Binding Protein/genetics , Disease Progression , Female , Humans , Infant , Male , Nerve Tissue Proteins/genetics , Prospective Studies , RNA-Binding Proteins/genetics , Retrospective Studies , SMN Complex Proteins , Spinal Muscular Atrophies of Childhood/genetics , Survival Analysis , Survival of Motor Neuron 2 Protein
12.
J Clin Epidemiol ; 61(4): 324-30, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18313556

ABSTRACT

OBJECTIVE: Recruitment of pediatric patients in randomized clinical trials is hampered by the rarity of many conditions and by ethical constraints. The objective of this paper is to give an overview of design options to obtain a statistically valid result while including a minimum number of subjects. STUDY DESIGN AND SETTING: Overview and discussion of several approaches to conduct valid randomized clinical trials in rare diseases and vulnerable populations. RESULTS: Sequential designs have been developed as efficient ways to evaluate accumulating information from a clinical trial, thereby reducing the average size of trials. Different sequential procedures exist, including group sequential designs, boundaries designs, and adaptive designs. The sample size attained at the end of the trial is unknown at the start. The sample size for a given set of alpha, beta, and effect size may turn out to be larger than with a classical fixed sample size approach. Simulations have shown that on average, sample sizes are smaller. CONCLUSION: There are several possibilities to optimize the number of subjects in a clinical trial. The rarity of many disorders in children and the ethical requirements in this patient population should not obstruct the performance of well-designed research to support clinical decision making.


Subject(s)
Epidemiologic Research Design , Randomized Controlled Trials as Topic/methods , Rare Diseases , Sample Size , Child , Ethics, Clinical , Humans , Randomized Controlled Trials as Topic/ethics
14.
ISA Trans ; 47(1): 53-9, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17870075

ABSTRACT

Model Predictive Control is a valuable tool for the process control engineer in a wide variety of applications. Because of this the structure of an MPC can vary dramatically from application to application. There have been a number of works dedicated to MPC tuning for specific cases. Since MPCs can differ significantly, this means that these tuning methods become inapplicable and a trial and error tuning approach must be used. This can be quite time consuming and can result in non-optimum tuning. In an attempt to resolve this, a generalized automated tuning algorithm for MPCs was developed. This approach is numerically based and combines a genetic algorithm with multi-objective fuzzy decision-making. The key advantages to this approach are that genetic algorithms are not problem specific and only need to be adapted to account for the number and ranges of tuning parameters for a given MPC. As well, multi-objective fuzzy decision-making can handle qualitative statements of what optimum control is, in addition to being able to use multiple inputs to determine tuning parameters that best match the desired results. This is particularly useful for multi-input, multi-output (MIMO) cases where the definition of "optimum" control is subject to the opinion of the control engineer tuning the system. A case study will be presented in order to illustrate the use of the tuning algorithm. This will include how different definitions of "optimum" control can arise, and how they are accounted for in the multi-objective decision making algorithm. The resulting tuning parameters from each of the definition sets will be compared, and in doing so show that the tuning parameters vary in order to meet each definition of optimum control, thus showing the generalized automated tuning algorithm approach for tuning MPCs is feasible.


Subject(s)
Algorithms , Fuzzy Logic , Genetics/statistics & numerical data , Forecasting , Hot Temperature , Industry , Thermodynamics
15.
Health Policy ; 122(12): 1287-1294, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30274934

ABSTRACT

In clinical trials, it is relevant to ask patients and/or their caregivers which aspects concerning their disease they consider important to measure when a new intervention is being investigated. Those aspects, useful as outcome measures in a trial, are of pivotal importance for the result of the trial and the subsequent decision-making. In rare diseases the choice of outcome measures may be even more important, due to the small numbers and heterogeneity of the patients that are included. We have developed a tool to involve patients in the determination of outcome measures and the choice of measurement instruments. This tool was developed together with a patient think tank, consisting of a group of rare disease patient representatives, and by interviewing end users. We have road-tested our tool in an ongoing trial, and evaluated it during a focus group meeting. The tool consists of three steps: 1) Preparation, 2) Consultation of patients, 3) Follow-up during which the consultation results are implemented in the trial design. The tool provides guidelines for researchers to include the patient's opinion in the choice of outcome measures in the trial design stage. We describe the development of the POWER-tool (Patient participation in Outcome measure WEighing for Rare diseases), and first experiences of the tool in an ongoing trial.


Subject(s)
Decision Making , Outcome Assessment, Health Care , Patient Participation/methods , Rare Diseases , Research Design , Caregivers , Clinical Trials as Topic , Focus Groups , Humans
16.
Clin Pharmacol Ther ; 103(3): 458-467, 2018 03.
Article in English | MEDLINE | ID: mdl-28555724

ABSTRACT

The pharmacokinetics (PK) of amoxicillin in asphyxiated newborns undergoing moderate hypothermia were quantified using prospective data (N = 125). The population PK was described by a 2-compartment model with a priori birthweight (BW) based allometric scaling. Significant correlations were observed between clearance (Cl) and postnatal age (PNA), gestational age (GA), body temperature (TEMP), and urine output (UO). For a typical patient with GA 40 weeks, BW 3,000 g, 2 days PNA (i.e., TEMP 33.5°C), and normal UO, Cl was 0.26 L/h (interindividual variability (IIV) 41.9%) and volume of distribution of the central compartment was 0.34 L/kg (IIV of 114.6%). For this patient, Cl increased to 0.41 L/h at PNA 5 days and TEMP 37.0°C. The respective contributions of both covariates were 23% and 27%. Based on Monte Carlo simulations we recommend 50 and 75 mg/kg/24h amoxicillin in three doses for patients with GA 36-37 and 38-42 weeks, respectively.


Subject(s)
Amoxicillin/pharmacokinetics , Anti-Bacterial Agents/pharmacokinetics , Hypothermia/metabolism , Aging/metabolism , Algorithms , Amoxicillin/administration & dosage , Anti-Bacterial Agents/administration & dosage , Birth Weight , Body Temperature , Cohort Studies , Computer Simulation , Female , Gestational Age , Humans , Infant, Newborn , Male , Monte Carlo Method , Prospective Studies , Urodynamics
17.
Stroke ; 35(6): 1410-4, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15087552

ABSTRACT

BACKGROUND AND PURPOSE: The Motor Activity Log (MAL) is a semistructured interview for hemiparetic stroke patients to assess the use of their paretic arm and hand (amount of use [AOU]) and quality of movement [QOM]) during activities of daily living. Scores range from 0 to 5. The following clinimetric properties of the MAL were quantified: internal consistency (Cronbach alpha), test-retest agreement (Bland and Altman method), cross-sectional construct validity (correlation between AOU and QOM and with the Action Research Arm [ARA] test), longitudinal construct validity (correlation of change on the MAL during the intervention with a global change rating [GCR] and with change on the ARA), and responsiveness (effect size). METHODS: Two baseline measurements 2 weeks apart and 1 follow-up measurement immediately after 2 weeks of intensive exercise therapy either with or without immobilization of the unimpaired arm (forced use) were performed in 56 chronic stroke patients. RESULTS: Internal consistency was high (AOU: alpha=0.88; QOM: alpha=0.91). The limits of agreement were -0.70 to 0.85 and -0.61 to 0.71 for AOU and QOM, respectively. The correlation with the ARA score (Spearman rho) was 0.63 (AOU and QOM). However, the improvement on the MAL during the intervention was only weakly related to the GCR and to the improvement on the ARA, Spearman rho was between 0.16 and 0.22. The responsiveness ratio was 1.9 (AOU) and 2.0 (QOM). CONCLUSIONS: The MAL is internally consistent and relatively stable in chronic stroke patients not undergoing an intervention. The cross-sectional construct validity of the MAL is reasonable, but the results raise doubt about its longitudinal construct validity.


Subject(s)
Arm , Disability Evaluation , Exercise Therapy/methods , Paresis/rehabilitation , Stroke Rehabilitation , Surveys and Questionnaires , Activities of Daily Living , Aged , Female , Humans , Male , Middle Aged , Paresis/diagnosis , Stroke/diagnosis , Treatment Outcome
18.
J Rehabil Med ; 33(3): 110-3, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11482350

ABSTRACT

The responsiveness of the Action Research Arm (ARA) test and the upper extremity motor section of the Fugl-Meyer Assessment (FMA) scale were compared in a cohort of 22 chronic stroke patients undergoing intensive forced use treatment aimed at improvement of upper extremity function. The cohort consisted of 13 men and 9 women, median age 58.5 years, median time since stroke 3.6 years. Responsiveness was defined as the sensitivity of an instrument to real change. Two baseline measurements were performed with a 2-week interval before the intervention, and a follow-up measurement after 2 weeks of intensive forced use treatment. The limits of agreement, according to the Bland-Altman method, were computed as a measure of the test-retest reliability. Two different measures of responsiveness were compared: (i) the number of patients who improved more than the upper limit of agreement during the intervention; (ii) the responsiveness ratio. The limits of agreement, designating the interval comprising 95% of the differences between two measurements in a stable individual, were -5.7 to 6.2 and -5.0 to 6.6 for the ARA test and the FMA scale, respectively. The possible sum scores range from 0 to 57 (ARA) and from 0 to 66 (FMA). The number of patients who improved more than the upper limit were 12 (54.5%) and 2 (9.1%); and the responsiveness ratios were 2.03 and 0.41 for the ARA test and the FMA scale, respectively. These results strongly suggest that the ARA test is more responsive to improvement in upper extremity function than the FMA scale in chronic stroke patients undergoing forced use treatment.


Subject(s)
Health Status Indicators , Outcome Assessment, Health Care , Stroke Rehabilitation , Aged , Chronic Disease , Female , Humans , Male , Middle Aged , Reproducibility of Results
19.
Ned Tijdschr Geneeskd ; 139(29): 1498-501, 1995 Jul 22.
Article in Dutch | MEDLINE | ID: mdl-7630457

ABSTRACT

OBJECTIVE: To evaluate the prevalence and incidence of thalassaemia major and sickle-cell disease in children. DESIGN: Descriptive nationwide epidemiological study. SETTING: Clinical Genetic Centre Utrecht. METHOD: Prevalence data were collected by a written survey among all 333 Dutch paediatricians (1992; response rate 99.1%). Incidence data are collected monthly by the Dutch Paediatric Surveillance Unit (1992/'93; response rate: 86%). RESULTS: In September 1992, 128 children were being treated by a paediatrician for sickle-cell disease. Two children had parents born in the Netherlands, but all children were of other ethnic origins, mainly from Surinam, the Dutch Antilles, Turkey and Africa; 50 children were born in the Netherlands. 31 children were under treatment for thalassaemia major, none of them of original Dutch descent; the most frequent ethnic backgrounds were Turkey and Morocco; 20 children were born in the Netherlands. From October 1992 till December 1993 (15 months) 18 children were newly diagnosed with sickle-cell disease, of whom 7 were born in the Netherlands, and 8 children were newly diagnosed with thalassaemia major, of whom 2 were born in the Netherlands. CONCLUSION: Sickle-cell disease and thalassaemia major are (still) rare diseases in the Netherlands. With the present migration and the increase of consanguineous marriage, they are expected to become a more important health issue.


Subject(s)
Anemia, Sickle Cell/epidemiology , Thalassemia/epidemiology , Adolescent , Anemia, Sickle Cell/genetics , Child , Child, Preschool , Epidemiologic Methods , Female , Genetic Carrier Screening , Humans , Incidence , Infant , Male , Prevalence , Thalassemia/genetics
20.
Ned Tijdschr Geneeskd ; 142(18): 1019-22, 1998 May 02.
Article in Dutch | MEDLINE | ID: mdl-9623203

ABSTRACT

OBJECTIVE: To investigate whether screening for carriership of sickle-cell anaemia and thalassaemia is desirable in the Netherlands, given the prevalence of the diseases, the possibilities of a screening test and the knowledge of the population at risk. DESIGN: Descriptive. SETTING: Wilhelmina Children's Hospital, Clinical Genetic Centre, Utrecht, the Netherlands. METHODS: In September 1992 Dutch paediatricians were treating 128 children with sickle-cell anaemia and 31 with thalassaemia major. Between October 1992 and December 1994, sickle-cell anaemia was diagnosed in 40 children and thalassaemia major in 14; of these, 16 and 4, respectively, had been born in the Netherlands. A protocol for the screening for carriership adjusted to the Dutch situation was drawn up in the past, with an estimate of the corresponding costs. Patients with sickle-cell anaemia or thalassaemia major, their families, care givers and persons without disease but originating from Surinam, the Netherlands Antilles, Turkey or Morocco were interviewed about their knowledge of these two diseases. RESULTS: The knowledge of the diseases was low among the Turkish and Moroccan populations, and very global among the Surinamese and Antillian populations. There was more belief in supernatural causes than in a genetic predisposition. CONCLUSION: Given the low number of newly diagnosed haemoglobinopathies in children born in the Netherlands, the poor knowledge of the disease of the population at risk, the difficulty in identifying the best moment in life for screening and the rather complicated screening method, a screening programme for carriership of haemoglobinopathies in the Netherlands is not opportune. Where sickle-cell anaemia is concerned, screening for this disease during the neonatal period might be considered.


Subject(s)
Genetic Testing/trends , Health Knowledge, Attitudes, Practice , Hemoglobinopathies/ethnology , Mass Screening/trends , Anemia, Sickle Cell/diagnosis , Anemia, Sickle Cell/genetics , Hemoglobinopathies/diagnosis , Hemoglobinopathies/genetics , Humans , Infant, Newborn , Morocco/ethnology , Netherlands/epidemiology , Netherlands Antilles/ethnology , Suriname/ethnology , Turkey/ethnology
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