Caregiver burden after stroke: a 10-year follow-up study of Polish caregivers for stroke patients.

BACKGROUND: A long-term assessment of stroke outcomes from the perspectives of patients and their caregivers is important for optimising long-term post-stroke care. The extended effects of stroke caregiving, particularly caregiver burden beyond 5 years since stroke, remain to be determined. Hence, this study aimed to determine caregiver burden at 10 years after stroke, compare the burden severity at 10 years with its levels at 5 years and 6 months after stroke, and identify predictors of the burden severity at 10 years post-stroke. METHODS: A longitudinal follow-up study including a group of first-ever stroke patients/informal continuous caregivers pairs was followed for 10 years and interviewed face-to face at their home setting. Caregiver burden was evaluated with the Caregiver Burden Scale. Potential predictors were examined using standardised measures and identified by applying the Classification and Regression Tree. RESULTS: A total of 40 caregiver/patient pairs participated in the study. At 10 years, 47.5% of the caregivers experienced a considerable burden. This was more than after 5 years (17.5%) and comparable to that after 6 months (37.5%), p < 0.003. Longer time spent caregiving, caregivers' weaker sense of coherence, more severe stroke, and caregivers' anxiety were the independent predictors of considerable burden 10 years after stroke. CONCLUSIONS: Caregivers' burden in the late chronic post-stroke phase is a significant problem, as nearly half of the caregivers experience a substantial burden. This problem mainly concerns individuals who spend at least 7 h daily caregiving and have a lower Sense of Coherence. The long-term evaluation of stroke consequences reported by stroke patients and their caregivers can be an important source of information for healthcare professionals in order to optimise the care and support they provide at various stages of life after stroke.

Fecal Fat Concentration and Excretion in the First 2 Years of Life: a Cross-Sectional Study.

OBJECTIVES: Data on pancreatic exocrine secretion in the youngest children are scarce. The aim of the study was to determine the range of normal values for fecal fat concentration (FFC) and fecal fat excretion (FFE) in infants and toddlers up to 2 years of age. METHODS: A total of 160 subjects aged 1 to 24 months (8 groups of 20: aged 1-3, 4-6 months, etc) were included in the study. In all children, FFC (%) and FFE (g/day) were assessed in 3-day stool collection. RESULTS: FFC correlated with age (r = -0.50, P < 0.0001). Of infants aged 1 to 3 months 65% had FFC higher than the <5% norm proposed for older children. The values of 90th/95th FFC percentile ranged from 9.7/13.0% at 1 month to 3.1/3.2% at 24 months. FFE did not differ between age groups. It was, however, higher than 4 and 3 g/day in 7.5% and 15.0% infants, respectively. The first detailed nomogram for the assessment of FFC and FFE in children aged 1 to 24 months was created. CONCLUSIONS: Healthy infants may have higher FFC and FFE than older children. We provide reference values, which should allow for both precise and facile FFC and FFE interpretation in clinical practice.

Long-term renal outcome in children with OCRL mutations: retrospective analysis of a large international cohort.

Background: Lowe syndrome (LS) and Dent-2 disease (DD2) are disorders associated with mutations in the OCRL gene and characterized by progressive chronic kidney disease (CKD). Here, we aimed to investigate the long-term renal outcome and identify potential determinants of CKD and its progression in children with these tubulopathies. Methods: Retrospective analyses were conducted of clinical and genetic data in a cohort of 106 boys (LS: 88 and DD2: 18). For genotype-phenotype analysis, we grouped mutations according to their type and localization. To investigate progression of CKD we used survival analysis by Kaplan-Meier method using stage 3 CKD as the end-point. Results: Median estimated glomerular filtration rate (eGFR) was lower in the LS group compared with DD2 (58.8 versus 87.4 mL/min/1.73 m2, P < 0.01). CKD stage II-V was found in 82% of patients, of these 58% and 28% had moderate-to-severe CKD in LS and DD2, respectively. Three patients (3%), all with LS, developed stage 5 of CKD. Survival analysis showed that LS was also associated with a faster CKD progression than DD2 (P < 0.01). On multivariate analysis, eGFR was dependent only on age (b = -0.46, P < 0.001). Localization, but not type of mutations, tended to correlate with eGFR. There was also no significant association between presence of nephrocalcinosis, hypercalciuria, proteinuria and number of adverse clinical events and CKD. Conclusions: CKD is commonly found in children with OCRL mutations. CKD progression was strongly related to the underlying diagnosis but did not associate with clinical parameters, such as nephrocalcinosis or proteinuria.

Is Venlafaxine More Effective than Escitalopram and Nortriptyline in the Management of Painful Symptoms in Patients with Major Depression?

BACKGROUND: Conflicting data regarding the efficacy of antidepressants of different mechanism of action on unexplained painful physical symptoms (UPPS) in depression have been published so far. OBJECTIVE: The aim of this study was to compare the impact of escitalopram (ESC), nortriptyline (NOR), and venlafaxine (VEN) on UPPS in patients with major depression. MATERIALS AND METHODS: Sixty patients, participants in the GENDEP study, with a diagnosis of depression according to the ICD-10 criteria were randomly assigned to treatment with ESC (10-30 mg, mean dose 15.2, standard deviation [SD]±9.2) or NOR (50-150 mg, mean dose 106.2, SD±8.2). Additionally, 30 patients who were treated with VEN (75-225 mg, mean dose 181.3, SD±8.8) were included. Before inclusion (day 0) and throughout the study (days 14, 28, 42, 56), the severity of pain was monitored using the visual analog scale. RESULTS: The patients treated with ESC, NOR, and VEN did not differ in the intensity of pain at days 0, 14, 28, 42, and 56. CONCLUSION: Our results do not support the hypothesis suggesting the superiority of VEN over ESC and NOR in the management of UPPS in major depression.

Fecal elastase-1 in healthy children up to 2 years of age: a cross-sectional study.

BACKGROUND: Fecal elastase-1 (E-1) levels in infants and young children may be expected to differ from those in adults and older children because of the immaturity of the gastrointestinal tract and the specificity of their diet. Despite the availability of data describing E-1 levels in the stools of preterm infants, older children, adults and subjects with malabsorption, there is still a lack of data regarding E-1 in healthy infants and toddlers. The aim of this cross-sectional study was to evaluate fecal E-1 concentrations in infants and children from 1 up to 24 months of age. MATERIAL AND METHODS: E-1 was measured in 160 healthy subjects aged 1-24 months (8 groups of 20: aged 1-3, 4-6 months, etc.) using an enzyme-linked immunosorbent assay (ELISA). RESULTS: Fecal E-1 concentrations ranged from 200 to 1695 µg/g of feces. No child had a fecal E-1 level below 200 µg/g of feces. Fecal E-1 concentrations did not significantly differ between age groups. However, fecal E-1 levels in the first 3 months were lower than in the second year of life (1-3 months vs 13-24 months, p=0.0230). A statistically significant correlation between the E-1 concentration and age was found (p=0.0007, r=0.2639; however, it does not affect the cut-off level of the reference values). The trend was rather exponential. Fecal E-1 values reached a plateau around the age of 6-10 months. CONCLUSIONS: Our study has shown that the fecal E-1 test can be reliably applied in infants and toddlers to confirm normal exocrine pancreatic function. However, within the first months of life fecal E-1 concentrations may be lower than later in life.

Determinants of Serum Glycerophospholipid Fatty Acids in Cystic Fibrosis.

The etiology of altered blood fatty acid (FA) composition in cystic fibrosis (CF) is understood only partially. We aimed to investigate the determinants of serum glycerophospholipids' FAs in CF with regard to the highest number of FAs and in the largest cohort to date. The study comprised 172 CF patients and 30 healthy subjects (HS). We assessed Fas' profile (gas chromatography/mass spectrometry), CF transmembrane conductance regulator (CFTR) genotype, spirometry, fecal elastase-1, body height and weight Z-scores, liver disease, diabetes and colonization by Pseudomonas aeruginosa. The amounts of saturated FAs (C14:0, C16:0) and monounsaturated FAs (C16:1n-7, C18:1n-9, C20:1n-9, C20:3n-9) were significantly higher in CF patients than in HS. C18:3n-6, C20:3n-6 and C22:4n-6 levels were also higher in CF, but C18:2n-6, C20:2n-6 and C20:4n-6, as well as C22:6n-3, were lower. In a multiple regression analysis, levels of seven FAs were predicted by various sets of factors that included age, genotype, forced expiratory volume in one second, pancreatic status and diabetes. FA composition abnormalities are highly prevalent in CF patients. They seem to be caused by both metabolic disturbances and independent clinical risk factors. Further research into the influence of CFTR mutations on fat metabolism and desaturases' activity is warranted.

The presence of thin glomerular basement membranes in various glomerulopathies.

Results of 61 cases of various glomerulopathies with thin glomerular basement membranes are presented. The largest group of 31 cases consisted of mesangial glomerulonephritis. The second largest group consisted of 19 patients with small glomerular lesions described as non-specific. This group stood out in both clinical presentations and in the higher diversity of lesions within the lamina densa of the basement membrane. The results of measurements of the lamina densa in various glomerulopathies were compared to those obtained in control groups consisting of thin basement membrane syndrome and submicroscopic glomerulonephritis.

Difficulties in differentiating thin basement membrane disease from Alport syndrome.

We examined a group of 83 patients (57 children and 26 adults) with thin basement membrane disease and 17 patients with Alport syndrome. We compared the clinical data and, above all, the morphological patterns of both disease entities, with particular focus on not very advanced changes which might lead to a misdiagnosis due to the non-detection of the early stages of Alport syndrome.

Comparison of Baseline Heart Rate Variability in Stable Ischemic Heart Disease Patients with and without Stroke in Long-Term Observation.

GOAL: Decreased heart rate variability (HRV) has predictive value in postinfarction as well as in ischemic stroke patients. However, it is unknown if ischemic heart disease (IHD) patients who are at high risk of stroke have different HRV profile. The goal of this study was to compare baseline HRV (traditional and novel indices) in stable IHD patients with and without stroke in long-term observation. METHODS: A total of 139 consecutive patients with stable IHD scheduled for coronary angiography were enrolled. Five-minute electrocardiogram readings were taken. Traditional and novel HRV measures were calculated. After 70.06 ± 4.297 months of follow-up, baseline HRV indices in patients who had had a stroke were compared with indices in patients without the aforementioned cerebrovascular event. RESULTS: During follow-up, 6 patients developed stroke. Compared to patients without such a cerebrovascular event, these patients with stroke had lower values for the following HRV indices: de Hann long-term irregularity (30,521 ± 32,767 versus 46,678 ± 25,328; P < .05), Yeh interval index (.0207 ± .0208 versus .0326 ± .0157; P < .05), Organ BAND (3.0563 ± 3.328 versus 4.515 ± 2.276; P < .05), Dalton standard deviation (SD) (17,887 ± 17,636 versus 29,859 ± 16,478; P < .05), Zugaib short-term variability (.004 ± .00416 versus .00622 ± .00418; P < .05), Zugaib long-term variability (.0161 ± .0151 versus .0247 ± .0115; P < .05), standard deviation of all NN intervals (8,954 ± 8,812 versus 16,724 ± 11,594; P < .05), total power (2,616 ± 4,855 versus 4,678 ± 4,653; P < .05), w2 (.71 ± .338 versus 1.719 ± 1.08; P < .05), w3 (1.399 ± .924 versus 2.552 ± 1.609; P < .05), and w4 (1.367 ± 1.705 versus 2.824 ± 2.027; P < .05). No significant differences in other analyzed indices were observed. CONCLUSIONS: Patients with IHD and stroke in long-term observation have different baseline profiles of HRV indices. Further investigations are needed to assess the usefulness of HRV analysis in stroke risk assessment.

[Detection and considering of nonlinear effects in regression modeling].

One of the basic problems solved in the research work is the search for causal relationships between the variables analyzed. Very important, but not the only requirement for the existence of causality is to demonstrate the occurrence of a statistically significant correlation and determine the shape of the present relationship (regression). In the vast majority of experimenters limited to the study of linear associations. The paper presents one of the simplest but effective method of enriching models with nonlinear terms.

Clock gene variants differentiate mood disorders.

Genetic variations in clock-related genes were hypothesized to be involved to in the susceptibility of mood disorders MD (both unipolar (UPD) and bipolar (BPD) disorders). In our work we investigated role of gene variants form four core period proteins: CLOCK, ARNTL, TIM and PER3. The total sample comprised from 744 mood disorders inpatients (UPD = 229, BPD = 515) and 635 healthy voluntary controls. The 42 SNPs from four genes of interest were genotyped. We used single polymorphisms, haplotypes, SNPs interactions and prediction analysis using classical statistical and machine learning methods. We observed association between two polymorphisms of CLOCK (rs1801260 and rs11932595) with BPDII and two polymorphisms of TIM (rs2291739, rs11171856) with UPD. We also detected ARNTL haplotype variant (rs1160996C/rs11022779G/rs1122780T) to be associated with increased risk of MD, BPD (both types). We established significant epistatic interaction between PER3 (rs2172563) and ARNTL (rs4146388 and rs7107287) in case of BPD. Additionally relation between PER3 (rs2172563) and CLOCK (rs1268271 and rs3805148) appeared in case of UPD. Classification and Regression Trees (C and RT) showed significant predictive value for 10 polymorphisms in all analyzed genes. However we failed to obtain model with sufficient predictive power. During analyses of sleep disturbances sample, we found carriers of homozygote variants (ARNTL: rs11022778 TT, rs1562438 TT, rs1982350 AA and PER3: rs836755 CC) showing more frequent falling asleep difficulties when compare to other genotypes carriers. Our study suggested a putative role of the CLOCK, TIM, ARNTL and PER3 and polymorphisms in MD susceptibility. In our analyses we showed association of specific gene variants with particular types of MD. We also confirmed necessity of performing separate analyzes for BPD and UPD patients. Comprehensive statistical approach is required even with individual symptoms analyses.

Fecal pyruvate kinase is not suitable for discrimination between inflammatory bowel disease exacerbation and acute gastroenteritis.

INTRODUCTION: In inflammatory bowel diseases (IBD) diarrhea can be caused by exacerbation and/or infectious agents. Fecal calprotectin (FC) is a well-established biomarker of intestinal inflammation in IBD. However, its usefulness in depiction of IBD exacerbation from infectious diarrhea is limited. The value of fecal pyruvate kinase isoenzyme type 2 (M2-PK) in this application remains unknown. AIM: To compare the performance of M2-PK and FC in discriminating between diarrhea caused by IBD and infectious agents. MATERIALS AND METHODS: One hundred three patients were enrolled for the study, including 32 with ulcerative colitis (UC), 21 with Crohn's disease (CD), 29 with acute diarrhea caused by rotavirus (AD-RV), and 21 with acute diarrhea caused by Salmonella enteritidis (AD-SE). M2-PK and FC were measured using ELISA. Areas under receiver operating characteristic curves (AUCs), sensitivities and specificities for both tests in distinguishing between patient subgroups with moderate to severe UC and CD from AD-RV and AD-SE were calculated. RESULTS: Differences in AUCs between M2-PK and FC for distinguishing UC [CD] from AD-RV were -0.06 (p < 0.028) [-0.10 (p < 0.0018)] and for differentiating UC [CD] from AD-SE were 0.03 (NS) [-0.19(p < 0.0011)].M2-PK sensitivities and specificities in distinguishing UC [CD] from AD-RV were 75.0%[71.4%] and 89.7% [89.7%] and for differentiation of UC [CD] from AD-SE were 56.3% [71.4%] and 95.2[57.1%]. CONCLUSIONS: The performance of M2-PK in distinguishing between children with moderate-to-severe IBD and patients with infectious gastroenteritis was inferior to FC. Neither test had sensitivity ands pecificity sufficient for everyday clinical application.

[The estimation of causal effect in observational studies]. / Oszacowanie wielkosci efektu przyczynowego w badaniach obserwacyjnych.

One of the frequently encountered problems in the statistical analysis of the data is the correct interpretation of the effects occurring under the influence of some kind of treatment used by the researcher or appearing without its share of action. In the first case we are dealing with an experimental study, in the second with the observational study. In the experimental study, the researcher has full control over the procedure of random allocation of cases to a group subjected to a predetermined factor and a group not exposed to the action (randomization). In the case of an observational study, also called a retrospective study there are often additional factors that modify both assigned to the same groups as well as specific actions for the test results. The article presents an example of the cause of this phenomenon and selected methods of minimizing the mentioned influence.

Proinflammatory cytokines in monitoring the course of disease and effectiveness of treatment with etanercept (ETN) of children with oligo- and polyarticular juvenile idiopathic arthritis (JIA).

BACKGROUND: The demonstration of the quantitative prevalence of specific cytokines in JIA formed the basis for the introduction of biological anticytokine drugs to treatment. Routine assessment of the concentration of these cytokines in blood serum may enable earlier decision making on the legitimacy of biological treatment (anti-TNF). The aim of the study was to assess the diagnostic value of TNFalpha, IL-6, and IL-1beta in monitoring the course of the disease and effectiveness of treatment with etanercept of children with oligo- and polyarticular JIA. METHODS: In a 1-year prospective study, cytokine levels were measured using ELISA in serum samples for 19 JIA patients in whom no clinical improvement was noted in spite of treatment with disease modifying antirheumatic drugs (DMARDs) and glucocorticosteroids (GCS). All the patients started treatment with ETN. The control group included healthy children (n = 18). RESULTS: Concentrations of TNF-a and IL-6 in blood serum at time 0 were significantly higher than in the control group. IL-6 concentration decreased during treatment with ETN in children in the inactive phase of the disease. Mean concentrations of TNF-a in serum increased several dozen times irrespective of clinical improvement. TNFalpha concentrations were statistically significantly higher in patients in the inactive phase of the disease in comparison with those in the active phase and correlated with the dose of ETN. Only the concentration of IL-6 correlated with the JADAS-27 value at all time points. CONCLUSIONS: We conclude that IL-6 may serve as a biomarker of activity of the disease in children with JIA treated with ETN.

Serum TNF-α levels and indicators of disease activity in children with oligoarticular juvenile idiopathic arthritis (oJIA) in the first year of the disease.

BACKGROUND: Juvenile idiopathic arthritis is the most common arthropathy in childhood. Clinical assessment in JIA patients is based on clinical examination and conventional parameters of inflammation. Regardless of the JIA form, a distinctive characteristic of JIA is joint inflammation, which is sustained by an imbalance between pro- and anti-inflammatory factors. A significant amount of research has confirmed elevated levels of TNF-alpha in the serum and synovial fluid of JIA patients. The aim of the study was to compare serum TNF-alpha levels and indicators of disease activity in children with newly diagnosed oJIA in the first year of the disease and to assess the diagnostic value of TNF-alpha. METHODS: In a 1-year prospective study, TNF-alpha levels were measured using ELISA in serum samples for 22 oJIA patients. The control group consisted of 16 healthy children. The data were correlated with disease activity indicators and CHAQ score. RESULTS: Concentrations of TNF-alpha were significantly higher in the study group than in the control group at time 0 [10.03 pg/mL (2.16 - 15.53) vs. 0.00 pg/mL (0.00 - 0.12); p < 0.001] and at time 2 [0.00 pg/mL (0.00 - 9.26) vs. 0.00 pg/mL (0.00 - 0.12); p = 0.014]. The analysis of changes in TNF-alpha concentrations in the study group over time showed no statistically significant differences. No correlation between concentrations of TNF-alpha and any of the analyzed indicators of disease activity and CHAQ was found. CONCLUSIONS: Assessment of TNF-alpha concentration in blood serum in children with oJIA has no diagnostic value in monitoring the severity of the disease and the effectiveness of treatment.

[Heliox augmented mechanical ventilation in the treatment of premature infants with respiratory distress syndrome]. / Wentylacja mechaniczna z zastosowaniem helioxu w leczeniu wczesniaków z zespolem zaburzen oddychania.

OBJECTIVE: The aim of the study was to assess the influence of mechanical ventilation with helium-oxygen mixture (heliox) on basic vital signs, oxygenation, acid-base balance and respiratory mechanics in newborns with respiratory distress syndrome (RDS), previously treated with surfactant. MATERIAL AND METHODS: The study was carried out in preterm newborns with respiratory failure requiring mechanical ventilation due to RDS, requiring Fi02>0.4 after a single dose of surfactant. Patients were ventilated using PC-SIMV Parameters of mechanical ventilation, respiratory function, oxygenation, acid-base balance and vital signs were recorded at baseline, one hour during and one hour after heliox ventilation. RESULTS: Ten newborns with RDS were enrolled in the study Mechanical ventilation with heliox did not affect vital signs and patient general condition remained stable during and after ventilation with heliox. Mechanical ventilation with heliox was associated with a statistically significant increase in tidal volume (mean 5.48 vs. 6.55 ml/kg). There were no significant changes in minute ventilation and peak expiratory flow rate. Mechanical ventilation with heliox allowed the use of significantly lower fractions of inspired oxygen (mean 0.55 vs. 0.35), with a significant decrease in the oxygenation index (mean 8.77 vs. 5.02) and alveolar-arterial oxygen tension difference (mean 263.81 vs. 113.28 mm Hg). After ventilation with this gas mixture was stopped, the patients required higher Fi02, 01 and AaD02 levels increased. CONCLUSIONS: Mechanical ventilation with heliox was safe, improved oxygenation and caused an increase in tidai, volume in newborns with RDS previously treated with surfactant.

[Do we always correctly interpret the results of statistical nonparametric tests]. / Czy zawsze prawidlowo interpretujemy wyniki statystycznych testów nieparametrycznych.

Mann-Whitney, Wilcoxon, Kruskal-Wallis and Friedman tests create a group of commonly used tests to analyze the results of clinical and laboratory data. These tests are considered to be extremely flexible and their asymptotic relative efficiency exceeds 95 percent. Compared with the corresponding parametric tests they do not require checking the fulfillment of the conditions such as the normality of data distribution, homogeneity of variance, the lack of correlation means and standard deviations, etc. They can be used both in the interval and or-dinal scales. The article presents an example Mann-Whitney test, that does not in any case the choice of these four nonparametric tests treated as a kind of gold standard leads to correct inference.

Impact of selected risk factors on motor performance in the third month of life and motor development in the ninth month.

Background: Proper motor development can be influenced by a range of risk factors. The resulting motor performance can be assessed through quantitative and qualitative analysis of posture and movement patterns. Methods: This study was designed as the cohort follow-up of the motor assessment and aimed to demonstrate, in a mathematical way, the impact of particular risk factors on elements of motor performance in the 3rd month and the final motor performance in the 9th month of life. Four hundred nineteen children were assessed (236 male and 183 female), including 129 born preterm. Each child aged 3 month underwent a physiotherapeutic assessment of the quantitative and qualitative development, in the prone and supine positions. The neurologist examined each child aged 9 month, referring to the Denver Development Screening Test II and assessing reflexes, muscle tone and symmetry. The following risk factors were analyzed after the neurological consultation: condition at birth (5th min Apgar score), week of gestation at birth, intraventricular hemorrhage, respiratory distress syndrome, and the incidence of intrauterine hypotrophy and hyperbilirubinemia determined based on medical records. Results: A combination of several risk factors affected motor development stronger than any one of them solely, with Apgar score, hyperbilirubinemia, and intraventricular hemorrhage exhibiting the most significant impact. Conclusions: Premature birth on its own did not cause a substantial delay in motor development. Nonetheless, its co-occurrence with other risk factors, namely intraventricular hemorrhage, respiratory distress syndrome, and hyperbilirubinemia, notably worsened motor development prognosis. Moreover, improper position of the vertebral column, scapulae, shoulders, and pelvis in the third month of life may predict disturbances in further motor development.

The clinical significance of electronic fetal heart rate monitoring in twins.

OBJECTIVES: Fully effective intrapartum cardiotocographic (CTG) fetal heart monitoring is still missing. Visual analysis is far from credibility. Additional, computerized analysis techniques were proposed however they did not substantially decrease possible risks of fetal asphyxia. In twin pregnancies the problem is even more complicated. Our goal is to find the most valuable parameters in intrapartum CTG surveillance in twins, based on actual FIGO criteria. MATERIAL AND METHODS: Study included 58 women in labor who had been admitted to Delivery Department of tertiary care hospital with twin pregnancy in a period of one year. The features of the CTG (e.g., baseline, oscillation, decelerations, brady- or tachycardia) were grouped to create three variables that were closest to the FIGO CTG scale. All three groups were compared according to neonatal status (Apgar score at 5 min ≥ 7 or < 7; pH value in umbilical artery ≥ 7.20, < 7.20 or < 7.10 and BE (base excess) > or ≤ -12). Fetal status and its acid - base equilibrium was compared either with long term variability (LTV), short term variability (STV), or percentage of the signal loss. RESULTS: Out of 58 twin pregnancies, a total of 116 babies were born. One baby was born dead. From this group, 11 deliveries were natural births and 47 deliveries were C-sections. None of the analyzed features (pH, BE, Apgar, CTG features except tracing length, CTG FIGO categories) were statistically different between groups of singleton and twin pregnancies, except percentage of C-sections. No differences were found either for STV or LTV and fetal status.org CTG categories. CONCLUSIONS: Prior to cardiotocographic tracing of twins during labor, ultrasound examination should be mandatory. Considerable loss of signal in CTG tracing in twins should provoke ultrasonographic confirmation of the fetal status.

[Statistical inference in the presence of missing data]. / Wnioskowanie statystyczne w przypadku wystepowania brakujacych danych.

In experimental studies and particularly in medical research the missing data frequently ap-pear. Their existence can strongly affect the conclusions drawn. Therefore, it is important to treat them in appropriate way. This paper discusses three ways of dealing with missing values using example of simulated data and compares the results obtained in each case. It was found that a properly conducted multiple imputation technique gives results most consistent with those that would be obtained if the lack of data does not exist.