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PubMed1987

The clinical use of the Ohmeda Automated Anesthesia Record Keeper integrated in the Modulus II Anesthesia System. A preliminary report.

While performing his complex array of tasks, the anesthesiologist is also responsible for maintaining an anesthetic record. Up to now, this has been done by hand. The clinical use of automated anesthesia record keeping is presently evaluated. The anesthesia records generated by the Ohmeda Automated Anesthesia Record Keeper integrated in the Modulus II Anesthesia System is compared to hand written records. The differences between the two records of identical patients are quantified as erroneous or missing data. With the criteria adapted, we found significant and clinically relevant differences which stress the importance of automated record keeping.

Anesthesiology↗

PubMed2006

Reasons for non-participation in follow-up research on eating disorders.

OBJECTIVE: Lack of participation in follow-ups is thought to be a serious bias in outcome research on eating disorders; however, little systematic knowledge exists about the problem. The present study aimed to delineate non-participation in long-term follow-up research, and explore the reasons for non-participation. METHOD: Eating disorder patients (N=840) entering a naturalistic, longitudinal multi-centre study were divided into participators (N=508) and non-participators (N=332) in 36-month follow-ups. Non-participators were further classified as either active (i.e. refused participation or failed to attend scheduled appointments) or passive non-participators (i.e. could not be traced). RESULTS: Active non-participators exhibited significantly lower levels of general and eating disorder psychopathology at intake compared to participators, while passive non-participators reported higher levels of hostility. DISCUSSION: Systematic exploration of non-participation in longitudinal research can help to mitigate the problem of indistinct results due to missing data. Barriers to successful longitudinal research and how to overcome non-participation at endpoint are discussed.

Adult↗

PubMed1996

Brief cognitive screening in a field survey of the oldest old.

A nationally representative survey of living conditions among persons aged 77 to 98 years included a short instrument for cognitive impairment consisting of items from the Mini-Mental State Examination (MMSE). Because of the wide range of social, health, and economic domains included in the survey, it was necessary that the instrument could be administered in a short time by interviewers without experience in neuropsychological testing. Because of the age of the subjects, the instrument must be relatively independent of sensory or motor disabilities, and be acceptable to both interviewers and older adults. There were very few problems with the use of the instrument and very little missing data. A cut-off point for cognitive impairment was ascertained for the items included in this instrument using other data sets where diagnostic confirmation was available. Being able to identify subjects who are probably cognitively impaired is helpful in a multipurpose survey study of the oldest old, both in documenting the cognitive status of the sample and in evaluating the quality of other information being collected in the study.

Age Distribution↗

PubMed2001

Measuring general health status in dementia: practical and methodological issues in using the SF-36.

The objective of this study was to examine the measurement properties of the Medical Outcomes Study (MOS) 36-Item Short-Form health survey (SF-36) in a representative sample of dementia patients. A total of 138 subjects with dementia were evaluated with the SF-36. They were recruited from 16 centers, including 7 university hospital centers. Dementia severity, demographic variables, co-morbidity and functional limitations were also measured. The measurements obtained were compared by source of information (patient, family proxy, and care provider proxy). Thirteen patients refused to complete this questionnaire. Help from the interviewer was necessary in 72.8% of the cases. The average completion time was 18.8 minutes. Missing data exist in only 5.6% of the cases on average, except among patients with severe dementia (Mini Mental State Examination <10). With regard to reliability, internal consistency was acceptable to good; Cronbach's a ranged from a low of 0.59 to a high of 0.92 across subscales (median 0.75). Test-retest intraclass correlation coefficients were moderate to good (range 0.51-0.81) except for Role emotional (0.17), Bodily pain (0.49) and Mental health (0.45). For patients with MMSE > or = 15, test-retest coefficients were better (range 0.53-0.90). Intraclass correlation coefficient suggests that proxies are a poor substitute for obtaining a patient's perspective of his/her health status. In conclusion, the SF-36 is unsuitable for severe dementia, because severity of disease mainly affected the feasibility, acceptability, and reproducibility of the instrument. This study, however, confirms that it is possible to question subjects with mild to moderate dementia on their health status.

Aged↗

PubMed2006

[Pain and quality of life following palliative radiotherapy of bone metastases].

BACKGROUND AND PURPOSE: Palliative irradiation is used to provide pain relief and to increase quality of life. Most studies exclude patients with advanced cancer disease and, therefore, a positive selection results. This prospective clinical study investigates the effect of palliative radiotherapy on pain and quality of life of patients with painful bone metastases. PATIENTS AND METHODS: 263 patients with bone metastases due to advanced cancer were observed with respect to pain and quality of life during a 2-month course of radiotherapy. Missing data were substituted by the LOCF method (last observation carried forward) to prevent a biased reduction of data. RESULTS: Radiotherapy resulted in pain relief. In the complete group, pain medication was not increased. Quality of life was not affected positively. Side effects of radiotherapy increased remarkably. CONCLUSION: Radiotherapy leads to pain relief. However, risks and benefits must be considered critically due to side effects.

Aged↗

PubMed1999

[Quality of life in skin diseases: methodological and practical comparison of different quality of life questionnaires in psoriasis and atopic dermatitis].

Aim of the present study was a comparison of four quality of life (QoL) questionnaires in 228 patients with psoriasis (PSO, n = 148) and atopic dermatitis (AD, n = 80) regarding feasibility, discriminant validity and sensitivity to change. Evaluating were performed before and after treatment in clinic. The following questionnaires were compared. 1) Freiburg Quality of Life Assessment for Dermatoses (FLQA-d), 2) Dermatology Life Quality Index (DLQI), 3) Chronic Skin Disease Questionnaire (CSDQ) and 4) questionnaire on everyday life (ALLTAG). All questionnaires were able to discriminate significant reductions of QoL in PSO and AD, as compared to controls. In parallel to the clinical improvement, all questionnaires showed QoL improvements as well, i.e. the questionnaires were sensitive to change. However, not all of the DLQI and ALLTAG scales were sensitive to change. Also, in some cases part of the scales of these questionnaires could not be calculated due to missing data. Otherwise, all questionnaires were valid and easy to handle. Thus, QoL of patients with PSO and AD can reliably be assessed by various questionnaires. Decisive for selection are the aim and the design of the study.

Adult↗

PubMed2003

AFLP analysis of genetic relationships among aromatic grapevines (Vitis vinifera).

Genotypic diversity has been detected among aromatic grapevines (Vitis vinifera) by molecular markers (AFLPs). The 22 primer-pairs generated a total of 1,331 bands of which 564 (40%) were polymorphic over all the genotypes. The bootstrap analysis pointed out that a large number of polymorphic bands (200-400) has to be used for a better estimation of the genetic distances among genotypes; 383 polymorphic AFLP bands were used for the cluster and the principal coordinate analyses because they did not present missing data across all the genotypes. The cluster analysis (UPGMA), based on polymorphic AFLP markers, revealed no relationship between the Moscato and Malvasia grapevines. The Malvasias, unlike the Moscatos distinguished by their distinct muscat aroma, have to be considered a more complex group because it includes muscat and non-muscat grapevines. The principal coordinate analysis (PCO) confirmed the pattern of the cluster analysis only for those varieties which presented a low coefficient of dissimilarity, while for the other varieties there was no correspondence between the two analyses. The pattern of aggregation among aromatic grapevines in the cluster and principal coordinate analyses does not support any classification that might include an aromatic grapevine group in V. vinifera. Even though some synonyms and homonyms are present among aromatic grapevines (V. vinifera), genetic diversity exists among genotypes in AFLP markers.

Cluster Analysis↗

PubMed2005

Permutation tests for the correlation among genetic distances and measures of heterosis.

It is often found that heterosis tends to increase with genetic distance of the parents, though the correlation is not usually very close. It is therefore important to test the null hypothesis that the correlation is zero. The present work shows that standard procedures tend to yield too liberal tests, owing to the lack of independence among genetic distances and among heterosis estimates. A valid alternative is to use a permutation test, which was first suggested by Mantel [(1967) Cancer Res 27: 209--220). This test is well-known among plant breeders and geneticists, who often use it to test the correlation among two distance matrices. Its use is not restricted to the comparison of distance matrices. This is demonstrated in the present work, using two published datasets on marker-based genetic distances of maize inbreds or populations and heterosis of their crosses. It is shown that the test is also applicable in the presence of missing data.

Breeding↗

PubMed2002

Diabetes in the parents of children with Type I diabetes.

AIMS/HYPOTHESIS: Previous studies have reported an excess of Type II (non-insulin-dependent) diabetes mellitus in parents of children with Type I (insulin-dependent) diabetes mellitus. We set out to characterise the clinical and immunogenetic features of diabetes in parents of affected children, and to test the hypothesis that there is no excess of Type II diabetes within this population. METHODS: Clinical details were collected from 3164 parents of 1641 children with Type I diabetes participating in the Bart's-Oxford study of childhood diabetes. Islet cell antibodies, antibodies to GAD and IA-2, and HLA class II genotype were determined in a subset of this group. Individuals were assigned a classification of Type I diabetes on the basis of clinical features and measurement of islet autoantibodies. RESULTS: Of 184 parents with diabetes, 138 (75 %) were on insulin. At least one islet autoantibody was detected in 90 (59 %) of 152 parents tested, and of 116 who were HLA-typed, 23 (20 %) had the highest risk genotype HLA-DRB1(*)03-DQA1*0501-DQB1(*)0201 / DRB1*04-DQA1(*)0301-DQB1*0302. Of 46 non-insulin-treated parents, 12 had islet autoantibodies. Of all parents, 141 (4.5 %) were therefore classified as having Type I diabetes, and 31 (0.98 %) as Type II diabetes; 12 could not be classified because of missing data or samples. CONCLUSION/INTERPRETATION: Autoimmune diabetes can present late and without immediate need for insulin treatment in parents of children with the disease. Previous studies have categorised this as Type II diabetes. Our study suggests that there is no excess of non-autoimmune diabetes in the families of children with Type I diabetes.

Adolescent↗

PubMed2004

P-QOL: a validated questionnaire to assess the symptoms and quality of life of women with urogenital prolapse.

To develop a simple, valid, reliable questionnaire to assess the severity of symptoms and their impact on the quality of life in women with urogenital prolapse. Women recruited from gynaecology outpatient clinics were asked to complete a prolapse quality of life questionnaire (P-QOL) before their hospital visit. At the time of the visit, they were examined supine using the International Continence Society (ICS) prolapse score (POP-Q). A second P-QOL was posted and completed by patients 2 weeks later. The validity was assessed by measuring levels of missing data, comparing symptom scores between affected and asymptomatic women and comparing symptom scores with objective prolapse stages. The internal reliability was assessed by measuring the Cronbach alpha coefficient; 155 symptomatic and 80 asymptomatic women were studied. Severity according to P-QOL strongly correlated with the vaginal examination findings (p < 0.01, rho > 0.5). The total scores for each P-QOL domain were significantly different between symptomatic and asymptomatic women (p < 0.001). All items achieved a Cronbach alpha greater than 0.80 showing good inter-rater reliability. The test-retest reliability confirmed a highly significant correlation between the total scores for each domain. A P-QOL questionnaire for English-speaking patients has been developed which is reliable and valid.

Adult↗

PubMed2005

Effectiveness of alendronate and etidronate in the treatment of osteoporosis in men: a prospective observational study.

The prevalence of osteoporosis in men is higher than previously assumed; consequently, numerous therapies are being investigated to treat these patients. The Canadian Database of Osteoporosis and Osteopenia patients (CANDOO) was analyzed to examine changes in bone mineral density (BMD) in consecutively seen osteoporotic men administered alendronate, etidronate or no bone-active drugs (control) over 1 year. A total of 244 men attending six Canadian osteoporosis clinics were included in the study (42 alendronate, 102 etidronate and 100 control). Multiple imputation was used to model missing data to provide a more robust statistical model. The imputed datasets (five) were analyzed using multivariable linear regression to determine differences between groups in the percent change of lumbar spine (LS) and femoral neck (FN) BMD from baseline to 1 year. Differences in the percent change in BMD from baseline were most notable at the LS in favor of alendronate (4.3%; 95% CI: 2.1, 6.6 ) and etidronate (2.1%; 95% CI: 0.3, 4.0) therapy when compared with controls. At the LS, alendronate therapy led to significantly greater (2.2%; 95% CI: 0.2, 4.2) gains in BMD as compared to etidronate therapy. Compared to controls, there were no significant differences in FN BMD with alendronate (2.1%; 95% CI: -0.4, 4.7) or etidronate therapy (0.9%; 95% CI: -1.1, 2.8), nor were there significant differences between bisphosphonate groups (1.3%; 95% CI: -1.1, 3.6, in favor of alendronate). While both alendronate and etidronate significantly increased LS BMD in osteoporotic men after 1 year in real-world settings, alendronate therapy resulted in significantly superior gains in LS BMD. The effect of these two bisphosphonates on fractures and FN BMD in osteoporotic men is likely positive, but requires further study.

Alendronate↗

PubMed2003

Evidence for recurrent inhibition of reciprocal inhibition from soleus to tibialis anterior in man.

Reciprocal inhibition between ankle flexors and extensors has been the subject of numerous studies in Man. They have demonstrated that this reciprocal inhibition is in all likelihood caused by a disynaptic pathway at least partly fed by Ia afferents. It is thus generally agreed that this reciprocally organized inhibition between ankle flexors and extensors in Man is similar to the reciprocal Ia inhibition described in the cat. This conclusion has, however, been challenged, when Jankowska and McCrea described in the cat a non-reciprocal group I inhibition involving interneurones co-excited by Ia and Ib afferents and mediating inhibition to both antagonistic and non-antagonistic motoneurones. The only way to distinguish between reciprocal Ia inhibition and non-reciprocal group I inhibition is to test if the inhibition is blocked by recurrent inhibition, since only Ia interneurones are inhibited by recurrent inhibition. In the present study, reciprocal inhibition from soleus to tibialis anterior was thus investigated following activation of soleus-coupled Renshaw cells in normal human subjects. It was found that reciprocal inhibition induced in tibialis anterior motoneurones by the activation of soleus group I afferents is deeply depressed by activation of soleus-coupled Renshaw cells. This finding provides the missing data to identify disynaptic inhibition between antagonistic ankle muscles as a reciprocal Ia inhibition.

Electric Stimulation↗

PubMed2003

A macroscopic approach to demography.

A canonical/lognormal model for human demography is established, specifying the net maternity function and the age distribution for mothers of new-borns using a single macroscopic parameter vector of dimension five. The age distribution of mothers is canonical, while the net maternity function normalizes to a lognormal density. Comparison of an actual population with the model serves to identify anomalies in the population which may be indicative of phase transitions or influences from levels outside the demographic. Tracking the time development of the parameter vector may be used to predict the future state of a population, or to interpolate for data missing from the record. In accordance with classical theoretical considerations of Backman, Prigogine, et al., it emerges that the logarithm of a mother's age is the most fundamental time variable for demographic purposes.

Adolescent↗

PubMed2004

Interlaminar astroglial processes in the cerebral cortex of great apes.

The present study was designed to document the architecture of neocortical astroglia in great apes, following glial fibrillary acidic protein immunohistochemistry. These anthropoid species were missing from previous phylogenetic descriptions of astroglia with interlaminar processes, a characteristic event of the cerebral cortex within the Primate Order. Pongo pygmaeus (orangutan), Gorilla gorilla (gorilla) and Pan troglodytes (chimpanzee) brain samples showed the typical "palisade" of interlaminar processes. Yet, those from Pan troglodytes were less uniform, showing extended cortical segments with astrocytic ("syncytial-type") appearance, intermingled with segments expressing the interlaminar "palisade". Present observations contribute to fill in missing data on the phylogenetic emergence of the cerebral cortex astroglial interlaminar processes. Considering the extreme consistency of the expression of astroglial interlaminar "palisades" among anthropoid species, this apparent variability among Pan individuals could be due to various possibilities, which are considered in this report.

Animals↗

PubMed2006

Influence of gender on attention-deficit/hyperactivity disorder in Europe--ADORE.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) in girls in Europe is poorly understood; it is not known whether they exhibit similar symptom patterns or co-existing problems and receive the same type of treatment as boys. OBJECTIVE: To examine gender differences for referral patterns, social demographic factors, ADHD core symptomatology, co-existing health problems, psychosocial functioning and treatment. METHODS: Baseline data from the ADHD Observational Research in Europe (ADORE) study, a 24-month, naturalistic, longitudinal observational study in 10 European countries of children (aged 6-18 years) with hyperactive/inattentive/impulsive symptoms but no previous diagnosis of ADHD, were analysed by gender. RESULTS: Data from 1,478 children were analysed: 231 girls (15.7%) and 1,222 boys (84.3%) (gender data missing for 25 patients). Gender ratios (girl:boy) varied by country, ranging from 1:3 to 1:16. Comparisons showed few gender effects in core ADHD symptomatology and clinical correlates of ADHD. Compared with boys, girls had significantly more parent-rated emotional symptoms and prosocial behaviour and were more likely to be the victim of bullying and less likely to be the bully. Girls and boys had similar levels of co-existing psychiatric and physical health problems, and received the same type of treatment. CONCLUSIONS: Fewer girls than boys are referred for ADHD treatment, but they have a similar pattern of impairment and receive similar treatment.

Adolescent↗

PubMed2006

Validity of the health-related quality of life assessment in the ADORE study: Parent Report Form of the CHIP-Child Edition.

OBJECTIVES: To examine the cross-sectional reliability and validity of the Parent Report Form of the Child Health and Illness Profile-Child Edition (CHIP-CE), a generic measure of health-related quality of life (HRQoL), in children with ADHD in the pan-European ADHD Observational Research in Europe (ADORE) study. METHODS: Parents of children with ADHD (aged 6-18 years) in 10 European countries completed the CHIP-CE at the baseline visit (n=1,477; data missing for one patient). Analyses included determination of internal consistency reliability, ceiling and floor effects, factor analysis, and Pearson's correlations between CHIP-CE and other scales used to measure ADHD severity, problems and family strain. RESULTS: Internal consistency reliability was good-to-excellent (Chronbach's alpha>0.70) for all CHIP-CE domains and subdomains, and almost no ceiling and floor effects were observed. Factor analysis of the subdomains yielded a 12-factor solution. The domainlevel factor analysis identified six factors, the four domains of Satisfaction, Comfort, Resilience and Risk Avoidance. The two subdomains of Achievement domain, Peer Relations and Academic Performance, were separate factors in this sample. There were moderate-to-high correlations between the CHIP-CE scales and measures of ADHD and family factors. The HRQoL of children in ADORE was dramatically lower than that of community youth,with mean CHIP-CE scores almost 2 standard deviations below community norms. CONCLUSIONS: The validity and reliability of CHIP-CE to measure HRQoL in children with ADHD across Europe was confirmed.

Adolescent↗

PubMed2006

The Family Strain Index (FSI). Reliability, validity, and factor structure of a brief questionnaire for families of children with ADHD.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) in children affects every member of the family. Practical tools are needed to assess the effects of ADHD on families to better understand and address the level of stress, strain and burden that families experience. OBJECTIVE: To provide the preliminary reliability, validity and factor structure of the Family Strain Index (FSI), a 6-item parent-report questionnaire. METHODS: The FSI was completed by 1,477 parents of children with ADHD (aged 6-18 years) at the baseline visit of the ADORE study in 10 European countries (data missing for one patient). RESULTS: The FSI taps into an overall experience of worry and interruptions of activities in families of children with ADHD, as a single factor was identified with excellent internal consistency (alpha=0.87). Despite its brevity, almost no ceiling (worst score) or floor (best score) effects were observed for families of these highly symptomatic children. This score distribution and the 5-point response options suggest that the FSI will be responsive to changes in the experience of family strain associated with children's ADHD treatment. CONCLUSION: The ease of completion and coherence of the underlying construct indicates that the FSI may be a practical clinical tool for monitoring changes in family strain associated with children's ADHD treatment.

Adolescent↗

PubMed2000

Hemispheric stroke following cardiac surgery: a case-control estimate of the risk resulting from ipsilateral asymptomatic carotid artery stenosis.

A case-control study was undertaken to determine if asymptomatic carotid artery stenosis (ACS) is independently associated with ipsilateral hemispheric stroke following cardiac surgery (CS). All CS patients (3069) who were at two hospitals between 1989 and 1994 were reviewed. Cases (31) selected for this study were those with hemispheric stroke within 30 days following CS. Controls (69) were taken from those without hemispheric stroke. Case-control analysis demonstrated that ACS of 50-90% and of 80-90% increased the risk of ipsilateral stroke 5.2-fold (95% confidence interval [CI] = 1.5-16.3, p = 0.01) and 24.3-fold (CI = 2.6-114.9, p = 0.002), respectively. Other variables with significant odds ratios (OR) were age > or =65 years (OR = 4.0, CI = 1.3-10.5, p = 0.01), peripheral vascular disease (OR = 3.4, CI = 1.3-8.8, p = 0.02), hypertension (OR = 3.0, CI = 1.2-7.0, p = 0.02), and female gender (OR = 3.0, CI = 1.2-7.1, p = 0.04). A second conservative analysis for missing data demonstrated a significant association for ACS of 80-90% alone (OR = 13.1, CI = 1.5-60.9, p = 0.01). This association remained significant after multivariate adjustment with propensity score stratification. ACS (80-90%) appears to be independently associated with ipsilateral hemispheric stroke following CS when evaluated against the present study variables. This finding supports the need for a properly conducted prospective natural history study, including an evaluation of aortic arch atherosclerosis, to determine the clinical relevance of this observation.

Aged↗