A longitudinal study of magnetic resonance spectroscopy Huntington's disease biomarkers

Putaminal metabolites examined using cross-sectional magnetic resonance spectroscopy (MRS) can distinguish pre-manifest and early Huntington's Disease (HD) individuals from controls. An ideal biomarker, however, will demonstrate longitudinal change over short durations. The objective here was to evaluate longitudinal in vivo brain metabolite profiles in HD over 24 months. Eighty-four participants (30 controls, 25 pre-manifest HD, 29 early HD) recruited as part of TRACK-HD were imaged at baseline, 12 months, and 24 months using 3T MRS of left putamen. Automated putaminal volume measurement was performed simultaneously. To quantify partial volume effects, spectroscopy was performed in a second, white matter voxel adjacent to putamen in six subjects. Subjects underwent TRACK-HD motor assessment. Statistical analyses included linear regression and one-way analysis of variance (ANOVA). At all time-points N-acetyl aspartate and total N-acetyl aspartate (NAA), neuronal integrity markers, were lower in early HD than in controls. Total NAA was lower in pre-manifest HD than in controls, whereas the gliosis marker myo-inositol (MI) was robustly elevated in early HD. Metabolites were stable over 24 months with no longitudinal change. Total NAA was not markedly different in adjacent white matter than putamen, arguing against partial volume confounding effects in cross-sectional group differences. Total NAA correlations with disease burden score suggest that this metabolite may be useful in identifying neurochemical responses to therapeutic agents. We demonstrate almost consistent group differences in putaminal metabolites in HD-affected individuals compared with controls over 24 months. Future work establishing spectroscopy as an HD biomarker should include multi-site assessments in large, pathologically diverse cohorts.

Short-term late-generation antibiotics versus longer term penicillin for acute streptococcal pharyngitis in children

BACKGROUND

The standard duration of treatment for children with acute group A beta hemolytic streptococcus (GABHS) pharyngitis with oral penicillin is 10 days. Shorter duration antibiotics may have comparable efficacy.

OBJECTIVES

To summarize the evidence regarding the efficacy of two to six days of newer oral antibiotics (short duration) compared to 10 days of oral penicillin (standard duration) in treating children with acute GABHS pharyngitis.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2012, Issue 3) which contains the Cochrane Acute Respiratory Infections Group's Specialized Register, MEDLINE (January 1966 to March week 3, 2012) and EMBASE (January 1990 to April 2012).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing short duration oral antibiotics to standard duration oral penicillin in children aged 1 to 18 years with acute GABHS pharyngitis.

DATA COLLECTION AND ANALYSIS

Two review authors scanned the titles and abstracts of retrieved citations and applied the inclusion criteria. We retrieved included studies in full, and extracted data. Two review authors independently assessed trial quality.

MAIN RESULTS

We included 20 studies with 13,102 cases of acute GABHS pharyngitis. The updated search did not identify any new eligible studies; the majority of studies were at high risk of bias. However, the majority of the results were consistent. Compared to standard duration treatment, the short duration treatment studies had shorter periods of fever (mean difference (MD) -0.30 days, 95% confidence interval (CI) -0.45 to -0.14) and throat soreness (MD -0.50 days, 95% CI -0.78 to -0.22); lower risk of early clinical treatment failure (odds ratio (OR) 0.80, 95% CI 0.67 to 0.94); no significant difference in early bacteriological treatment failure (OR 1.08, 95% CI 0.97 to 1.20) or late clinical recurrence (OR 0.95, 95% CI 0.83 to 1.08). However, the overall risk of late bacteriological recurrence was worse in the short duration treatment studies (OR 1.31, 95% CI 1.16 to 1.48), although no significant differences were found when studies of low dose azithromycin (10 mg/kg) were eliminated (OR 1.06, 95% CI 0.92 to 1.22). Three studies reported long duration complications. Out of 8135 cases of acute GABHS pharyngitis, only six cases in the short duration treatment versus eight in the standard duration treatment developed long-term complications in the form of glomerulonephritis and acute rheumatic fever, with no statistically significant difference (OR 0.53, 95% CI 0.17 to 1.64).

AUTHORS' CONCLUSIONS

Three to six days of oral antibiotics had comparable efficacy compared to the standard duration 10-day course of oral penicillin in treating children with acute GABHS pharyngitis. . In areas where the prevalence of rheumatic heart disease is still high, our results must be interpreted with caution.

Immunosuppressive therapy without hematopoietic growth factor exposure in pediatric acquired aplastic anemia

Immunosuppressive therapy (IST) is recommended for children with acquired aplastic anemia (AA) who lack a human leukocyte antigen (HLA)-matched sibling donor for hematopoietic cell transplantation (HCT). Hematopoietic growth factors have often been included in IST supportive care, but prolonged exposure may increase the risk of secondary clonal evolution. The authors evaluated response, survival, and the incidence of clonal evolution following cyclosporine-based IST without hematopoietic growth factor exposure in a population-based pediatric cohort, identified retrospectively. Forty-five patients with a median age of 7.3 years (range 1.2-17.0 years) were included. Partial (PR) and complete (CR) response was achieved in 82% and 64%, at a median of 55 days (range 11-414 days) and 7.6 months (range 2.8-82.2 months), respectively. Patients with associated seronegative hepatitis had an increased likelihood of PR and CR on multivariate analyses (PR: hazard ratio [HR] 3.15, 95% confidence interval [CI] 1.40, 7.11; CR: HR 2.99, 95% CI 1.35, 6.62), whereas older children were less likely to achieve IST response than children younger than 5 years at diagnosis. Five- and 10-year overall survival was 96% ± 4% and 90% ± 7%, respectively, and 5-year failure-free survival was 63% ± 8%. There was no infection-related mortality, although 16.4% of patients had at least 1 episode of documented bacteremia. The 5-year cumulative incidence of relapse was 12.9% and of clonal evolution was 3.2%. The authors conclude that children with AA who receive IST without hematopoietic growth factor support have excellent response and survival outcomes and a low incidence of clonal evolution.

Aminophylline in bradyasystolic cardiac arrest: a randomised placebo-controlled trial

BACKGROUND

Endogenous adenosine might cause or perpetuate bradyasystole. Our aim was to determine whether aminophylline, an adenosine antagonist, increases the rate of return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest.

METHODS

In a double-blind trial, we randomly assigned 971 patients older than 16 years with asystole or pulseless electrical activity at fewer than 60 beats per minute, and who were unresponsive to initial treatment with epinephrine and atropine, to receive intravenous aminophylline (250 mg, and an additional 250 mg if necessary) (n=486) or placebo (n=485). The patients were enrolled between January, 2001 and September, 2003, from 1886 people who had had cardiac arrests. Standard resuscitation measures were used for at least 10 mins after the study drug was administered. Analysis was by intention-to-treat. This trial is registered with the ClinicalTrials.gov registry with the number NCT00312273.

FINDINGS

Baseline characteristics and survival predictors were similar in both groups. The median time from the arrival of the advanced life-support paramedic team to study drug administration was 13 min. The proportion of patients who had an ROSC was 24.5% in the aminophylline group and 23.7% in the placebo group (difference 0.8%; 95% CI -4.6% to 6.2%; p=0.778). The proportion of patients with non-sinus tachyarrhythmias after study drug administration was 34.6% in the aminophylline group and 26.2% in the placebo group (p=0.004). Survival to hospital admission and survival to hospital discharge were not significantly different between the groups. A multivariate logistic regression analysis showed no evidence of a significant subgroup or interactive effect from aminophylline.

INTERPRETATION

Although aminophylline increases non-sinus tachyarrhythmias, we noted no evidence that it significantly increases the proportion of patients who achieve ROSC after bradyasystolic cardiac arrest.

Are components of a comprehensive medical assessment predictive of work disability after an episode of occupational low back trouble?

STUDY DESIGN

One hundred fifty-nine subacute low back work-injured patients completed a full medical assessment at baseline. A full repeat examination was performed 3 months later, when return-to-work status was determined.

OBJECTIVE

To determine the prognostic value of a comprehensive medical assessment for the prediction of return-to-work status.

SUMMARY OF BACKGROUND DATA

A systematic review of the work disability prediction literature of low back trouble prognosis revealed that no high-quality studies included a full medical history and physical examination in the design. The results of studies included in the systematic review were equivocal with respect to predictive usefulness of medical variables.

METHODS

Participants completed medical history questionnaires and then were clinically examined by one of six experienced examiners (three physicians and three physiotherapists). Return-to-work status was measured 3 months later, and predictive validity was evaluated using logistic regression modeling.

RESULTS

Medical variables (, medical history subscales, physical examination subscales, and lumbar range-of-motion tests) showed modest correct classification rates varying between 61.6% and 69.1% for participants.

CONCLUSIONS

Comprehensive medical assessments play a crucial role in the early identification of serious pathology after low back trouble. We were unable to identify, however, any medical evaluation variables that would account for significant proportions of variance in return to work. The weight of evidence obtained in this study suggests that injured workers' subjective interpretations and appraisals may be more powerful predictors of the course of postinjury recovery than exclusively medical assessments.

Reliability of the lumbar flexion, lumbar extension, and passive straight leg raise test in normal populations embedded within a complete physical examination

STUDY DESIGN

The study measured the reliability of the passive straight leg raise (SLR) test and lumbar range of motion (LROM) tests measured as continuous variables embedded within a comprehensive physical examination.

OBJECTIVES

To determine the reliability of the SLR and LROM test scores when they are measured with a Cybex electronic inclinometer (Lumex, Inc., New York, NY) within a physical examination.

SUMMARY OF BACKGROUND DATA

Good published empirical reliability exists for the Cybex and for SLR and LROM tests when the measurements are taken in isolation from other physical examination procedures. Reliability of the Cybex for continuous SLR and LROM measurement within a physical examination has not been assessed, however.

METHODS

Forty-five participants were seen by one of two physician/physiotherapist teams. Participants were examined by both team members. The first examiner conducted the first tests and retested 1 week later (intrarater reliability). The second examined the participants the day after their first appointment (inter-rater reliability).

RESULTS

Only two scores showed substantial reliability (defined as r > or = 0.60). These scores were left (r = 0.81) and right (r = 0.79) SLR intrarater reliability. All other scores fell below the specified cutoff.

CONCLUSIONS

SLR and LROM scores used clinically are collected during comprehensive physical examinations. Most scores gathered under these conditions were not reliable. These findings have implications for the use of clinically derived SLR and LROM scores.

Commentary on the American Medical Association guides' lumbar impairment validity checks

STUDY DESIGN

The American Medical Association's (AMA) Guides to the Evaluation of Permanent Impairment range of motion-based (ROM) lumbar impairment model validity checks were reviewed. Published literature of lumbar ROM (LROM) testing also was reviewed for application of the AMA validity checking protocols.

OBJECTIVE

The utility and feasibility of use of the AMA Guides' ROM lumbar impairment ratings were examined.

SUMMARY OF BACKGROUND DATA

Although they appear to be essential components of the ROM model, few published studies report use of these validity checks. Of at least 22 reviewed studies of LROM testing, only six studies included at least three measurements (the bare minimum) of LROM. Furthermore, only two (9.1%) reported performance of the LROM validity check. Only one, however, reported the results.

METHODS

English language journals were searched on Medline using "region, lumbar," "range of motion," "validity of results," "observer variation," and "low back pain" as title and subject search terms. The study methodologies approximating the AMA Guides' specifications were included in the analysis.

RESULTS

Under normal conditions of ROM measurement, 33% of three consecutive lumbar flexion and 27% of three consecutive lumbar extension measurements failed the LROM validity check. In addition, across three different experimental sessions (each with more than three consecutive LROM measurements taken) only 15 participants (33%) had valid flexion scores and only 24 participants (53%) had valid extension scores across all three sessions.

CONCLUSION

Technical complications inherent in the ROM-based impairment-rating model render the validity checks difficult to perform satisfactorily and thus rarely used.

Analysis of the convergent and discriminant validity of published lumbar flexion, extension, and lateral flexion scores

STUDY DESIGN

Articles reflecting the convergent or discriminant validity of the lumbar range of motion tests were reviewed and compared. Mean scores and standard deviations for lumber range of motion from healthy control subjects were plotted against those from patients with low back injuries.

OBJECTIVE

To use published research to analyze the convergent and discriminant validity of lumbar range of motion tests for the characterization of low back pain and injury.

SUMMARY OF BACKGROUND DATA

Several publications have addressed lumbar range of motion validity. Individual studies suggest that the tests possess convergent validity, but that their discriminant validity is indeterminate.

METHODS

English-language journals were searched on Medline using "region," "lumbar," "range of motion," "validity of results," "observer variation," and "low back pain" as title and subject search terms. The study methods approximating the specifications of the American Medical Association Guides to the Evaluation of Permanent Impairment were included in the analysis.

RESULTS

Convergent validity research showed inconsistent relations between inclinometric and radiographic lumbar range of motion measurements. Some studies showed strong relation, whereas others showed essentially no relation between the two techniques. Correlations between lumbar range of motion scores and spinal disability and function were similarly inconclusive. Studies reporting mean scores and standard deviations for lumbar range of motion measurements showed a high degree of overlap between the scores of participants with low back injuries and those without such injuries.

CONCLUSIONS

Convergent and discriminant validities of the lumbar range of motion tests currently require further substantiation. Absolute lumbar range of motion scores may not be suitable as the sole determinants of low back pathology diagnosis. Implications for using the lumbar range of motion tests to characterize low back injuries in medicolegal situations are discussed.

Inhaled budesonide in addition to oral corticosteroids to prevent asthma relapse following discharge from the emergency department: a randomized controlled trial

CONTEXT

Relapses of acute asthma following emergency department (ED) discharge can be reduced with systemic corticosteroid treatment. However, whether inhaled corticosteroids (ICSs) provide additional benefit is not known. Objective To determine whether the addition of ICSs to oral corticosteroid treatment would reduce relapses in patients with acute asthma discharged from the ED.

DESIGN AND SETTING

Placebo-controlled, double-blind, randomized clinical trial conducted in a community teaching hospital ED in Canada between November 1995 and September 1997, with a 21-day follow-up.

PARTICIPANTS

A total of 1006 consecutive patients aged 16 to 60 years presented to the ED with acute asthma; after excluding those using oral and/or inhaled corticosteroids as well as those meeting other exclusion criteria, 188 were included in the study.

INTERVENTIONS

Patients were discharged with a nontapering course of oral prednisone (50 mg/d) for 7 days. In a double-blind fashion, patients were randomly assigned to 1600 microg/d of inhaled budesonide (n = 94) or identical placebo (n = 94) for 21 days.

MAIN OUTCOME MEASURES

Incidence of relapse, defined as an unscheduled visit for worsening asthma symptoms, in budesonide vs placebo groups. Secondary outcomes included response to the Asthma Quality of Life Questionnaire, beta2-agonist use, symptom score, global asthma improvement assessment, and pulmonary function.

RESULTS

Five patients in the budesonide group and 3 in the placebo group either dropped out or were lost to follow-up but were included in primary analyses. After 21 days, 12 (12.8%) of 94 patients in the budesonide group experienced a relapse compared with 23 (24.5%) of 94 in the placebo group, a 48% relapse reduction (P=.049). Asthma Quality of Life Questionnaire scores were higher (better quality) in the budesonide group (P=.001), as well as for all domain scores (P=.001 to .01). Fewer beta2-agonist activations were used at the end of the trial by patients receiving budesonide (2.4/d vs 4.2/d; P=.01). Symptom scores (P=.001 to .004) and self-assessed asthma improvement scores (based on a 7-point Likert scale) (6.2 vs 5.2; P<.001) were higher (indicating fewer symptoms) for budesonide vs placebo. There were no differences in pulmonary function between the groups (peak expiratory flow rate: budesonide, 437 vs placebo, 453 L/min; P= .39) at 21 days. Using this approach, as few as 9 patients would require budesonide to prevent 1 relapse.

CONCLUSIONS

Patients discharged from the ED following treatment for acute asthma benefit from added treatment with high-dose inhaled budesonide for 21 days compared with oral corticosteroids alone.

Are combinations of questions better than individual questions for detecting sensitization to mite allergen?

Previous studies have found that questions are considerably less sensitive for predicting sensitization to dust mites than to pollens or to household pets. We studied 1160 children with respiratory symptoms to find whether the sensitivity for predicting mite allergy could be increased by asking several rather than single questions. Parents accompanying the children were asked standardized validated questions. Of the four individual questions relevant to mites, the one with the highest sensitivity for predicting a positive skin prick test to this allergen was whether the symptoms were worse when the house was being swept, vacuumed or dusted (29.8%). If an affirmative answer to that question, or to any of the other three questions, was taken as predictive of sensitization, the sensitivity increased to 54.2%. However, requiring only a single affirmative answer to this combination of questions decreased the specificity. The sensitivity of the combination of questions was comparable to that of questions for predicting positive tests to tree pollens (56.4%), cats (56.4%), grass pollens (52.5%) and dogs (51.4%). We conclude that asking a combination of questions is an useful for indicating possible sensitization to dust mite as are questions for detecting sensitization to other common inhalant allergens.

The accuracy of features in the clinical history for predicting atopic sensitization to airborne allergens in children

BACKGROUND

The clinical history is given considerable weight when one decides which allergens are responsible for a patient's symptoms, and in research studies the clinical history has been used as the "gold standard" with which different tests for allergy are compared.

OBJECTIVES

To determine whether standardized questions accurately predict replies to detailed questions asked by an experienced allergist, and to assess the utility of certain standardized questions for predicting sensitization to individual allergen groups.

METHODS

Trained interviewers put standardized questions to parents of 1160 children, aged 1 to 17 years, who had respiratory symptoms and had been newly referred to the allergy clinic of a children's hospital. For the first 151 of the subjects the answers were compared with those elicited by questions asked by a pediatric allergist. Skin prick tests and pollen counts were performed by a technologist.

RESULTS

The standardized questions had an accuracy for predicting the allergist's history of 93% to 97% for all questions except one. The standardized questions with the highest accuracy for predicting the skin test results to the appropriate allergens were the following: for mite, improvement in symptoms when outdoors (66.8%) and when in dry areas 69.4%), and aggravation during house cleaning (65.9%) and when bed making (70.6%); for dog, symptoms when with dogs (80.6%); for cat, symptoms when with cats (77.3%); for tree pollen, symptoms worse in April (70.8%) and when among trees in March and April (80.8%); and for grass pollen, exacerbation in June (69.2l%) and during lawn mowing (71.2%). Although specificity was generally above 80%, sensitivity was variable, ranging from 11% to 56%.

CONCLUSIONS

The standardized questions accurately predicted a detailed history obtained by an experienced allergist. Because standardized questions are reproducible they are the preferred method of history taking for research projects. Because several of the standardized questions have a high specificity they are useful for excluding sensitization to individual allergen groups, but because they have only a modest sensitivity, they are less helpful for detecting those who are sensitized to individual allergen groups.

Allergic rhinitis and recurrent epistaxis in children

BACKGROUND

Many allergists, but few otolaryngologists, consider allergic rhinitis to be a common cause of nosebleeds in childhood.

OBJECTIVE

To determine whether the two conditions are related, and whether epistaxis could be due solely to the local effects of nasal symptoms.

METHODS

We studied 557 children who were referred consecutively to an allergy clinic of a children's hospital. Standardized questions were put to their accompanying parents, and skin prick tests were performed on the children, using common local inhalant allergens.

RESULTS

On univariate analysis children who had both nasal symptoms and a positive skin test were found to have recurrent nosebleeds more frequently (20.2%) than had those with nasal symptoms on their own (9.9%), a positive skin test alone (3.4%), or neither (2.1%). Similarly, on logistic regression the odds ratio (OR) of nosebleeds was 3.3, 1.3, 1.65, and 1, respectively. Nosebleeds were more common in those who owned a dog or a cat and had a positive skin test to that species than in the remainder of the children (27.8% vs 10.8%).

CONCLUSIONS

Allergic rhinitis is commonly associated with recurrent epistaxis. In many children it appears that nosebleeds are due to nasal symptoms plus some abnormality that is found in the atopic state: a disorder of hemostasis is suspected as the contributing factor.

The Canadian Multicenter Double-blind Randomized Controlled Trial of ursodeoxycholic acid in primary biliary cirrhosis

Ursodeoxycholic acid, a dihydroxyl bile acid normally present in human beings in minimal amounts, becomes incorporated into the bile salt pool when taken orally. In cholestasis, bile acids are retained in the liver and are hepatotoxic. Ursodeoxycholic acid is the least-known hepatotoxic bile acid, has choleretic properties and is reported to benefit patients with chronic cholestasis. In a nationwide Canadian controlled trial, 222 patients with primary biliary cirrhosis were treated with ursodeoxycholic acid (14 mg/kg/body wt/day) or placebo for 24 mo. Only patients with a diagnosis confirmed by liver biopsy and serum positive for antimitochondrial antibodies were enrolled; 88% were symptomatic on entry. The primary outcome measure was percent change in total serum bilirubin from baseline to final follow-up. Treated patients (111) and controls (111) were comparable with regard to age, gender, biochemical parameters and liver histological condition. Although treatment was not associated with any improvement in symptoms, ursodeoxycholic acid therapy caused the bilirubin to fall significantly within the first 3 mo of therapy (p < 0.001). Significant falls in serum alkaline phosphatase, aminotransferases, cholesterol and IgM levels were also noted in the treated group. Improvement in some histological features was observed but there was no difference between the groups in the number of patients who reached the endpoints of death or liver transplantation. Ursodeoxycholic acid, given to patients with primary biliary cirrhosis, leads to an improvement in serum markers of cholestasis. A larger sample size is needed to determine whether ursodeoxycholic acid therapy has a beneficial effect on the survival of patients with primary biliary cirrhosis.

Observer agreement for respiratory signs and oximetry in infants hospitalized with lower respiratory infections

To determine observer agreement for a clinical score and oximetry in lower respiratory infection in children less than 2 yr of age, a convenience sample of 56 infants hospitalized with bronchiolitis or pneumonia was assessed independently by two observers. A total of 12 infants had chronic lung disease of prematurity or congenital heart disease. Infants in whom oxygen supplementation could not be discontinued for at least 5 min were excluded. A severity score was assigned for each of four categories (respiratory rate, retractions, wheeze, and general appearance). A total for each patient was obtained by summing the score for each category. Oxygen saturation was measured using a Nellcor oximeter. Agreement beyond chance was measured using the kappa statistic. The relationship between observers for total score and oximetry and the mean total score and mean oximetry value for each patient was expressed as a Pearson correlation coefficient. A total of 56 infants and children were studied: 2 had pneumonia, 11 had an exacerbation of pulmonary signs and symptoms with their underlying cardiac or pulmonary disease, and 43 had bronchiolitis. Kappa was 0.48 for general assessment, 0.38 for respiratory rate, 0.31 for wheeze, and 0.25 for retractions. All values were statistically significantly greater than 0 at p less than 0.01. Correlations for total score and for oximetry were 0.68 and 0.88, respectively. The median difference between oximetry readings was 1. The correlation coefficient between total score and oximetry was -0.04. The limited agreement for clinical signs makes comparison of patient illness severity between studies difficult.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of treatment on pregnancy among couples with unexplained infertility

Our objective was to determine the effect of treatment on the likelihood of pregnancy among couples with unexplained infertility. We used a nonrandomized, prospective, multicentered cohort analytic study, with mean follow-up time of 14.5 months (range, 0.5-46 months). The subjects were 470 couples who attended infertility clinics affiliated with medical schools in Canada, in whom no abnormality was found after investigation. They were drawn from a total of 2,106 couples registered from April 1, 1984 to March 31, 1987. Of these, 130 couples were selected for treatment at the discretion of the care givers; 340 couples were not treated. Selection for treatment resulted in imbalance between the groups: the treated couples had a longer mean duration of infertility (48 vs. 36 months), and were more likely to have had a laparoscopy as part of the investigation (72% vs. 48%). No specific protocol of treatment was used. Treatments most commonly used were clomiphene (87); gonadotropins (31); intrauterine insemination (20); IVF or GIFT (16); bromocriptine (12); 43 couples had two treatments, and 11 had three treatments. The only important determinants of treatment (logistic regression) were time under observation and laparoscopy status. Duration of infertility was only a minor determinant of treatment. Crude, unadjusted pregnancy rates were 25% for the treated group and 34% for the untreated group. The early occurrence of pregnancy in the untreated couples accounted for much of this difference. After adjustment for baseline differences between the groups and times to and under treatment with proportional hazards analysis, the cumulative probability of pregnancy is 2.0 (95% CI 1.3 to 3.1) times as high with treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Agreement among reviewers of review articles

OBJECTIVE

To assess the consistency of an index of the scientific quality of research overviews.

DESIGN

Agreement was measured among nine judges, each of whom assessed the scientific quality of 36 published review articles. ITEM SELECTION: An iterative process was used to select ten criteria relative to five key tasks entailed in conducting a research overview.

SAMPLE

The review articles were drawn from three sampling frames: articles highly rated by criteria external to the study; meta-analyses; and a broad spectrum of medical journals. JUDGES: Three categories of judges were used: research assistants; clinicians with research training; and experts in research methodology; with three judges in each category.

RESULTS

The level of agreement within the three groups of judges was similar for their overall assessment of scientific quality and for six of the nine other items. With four exceptions, agreement among judges within each group and across groups, as measured by the intraclass correlation coefficient (ICC), was greater than 0.5, and 60% (24/40) of the ICCs were greater than 0.7.

CONCLUSIONS

It was possible to achieve reasonable to excellent agreement for all of the items in the index, including the overall assessment of scientific quality. The implications of these results for practising clinicians and the peer review system are discussed.

The value of semen analysis and sperm function assays in predicting pregnancy among infertile couples

Over a 2-year period, 227 couples were evaluated by an extended assessment of the male partner's ejaculate. This extended assessment comprised sperm penetration of denuded hamster oocytes, ability of sperm to penetrate synthetic mucus, and the adenosine triphosphate (ATP) content of whole semen. In proportional hazards analysis adjusting for the contribution of clinical and other seminal variables, the sperm penetration assay (SPA) test was a predictor of pregnancy in the subgroup with normal conventional seminal variables (greater than 40 million motile sperm per ejaculate). When the SPA result was 20% or more the probability of pregnancy was 3.7 times higher; the performance of the SPA as a diagnostic test was better in the couples with treated tubal disease than in other diagnostic categories.

Factors XI and XII are low in subjects with liver disease

We prospectively measured levels of factors XI and XII in parallel with other coagulation factors in 39 unselected patients with liver disease and in 20 control subjects. Mean levels of factors XI and XII in subjects with liver disease were significantly reduced, being 58% and 61%, respectively, compared with 100% and 94% in controls. Reductions in levels of factors XI and XII were most pronounced in those subjects with low serum albumin. The partial thromboplastin time (APTT) reflected low levels of either factor XI or XII and was most prolonged when both were low, but cause and effect was not demonstrated. Low levels of these factors may explain previous reports of poor response of APTT to infusions of prothrombin complex concentrates. Finally, these low levels strongly suggest that factors XI and XII are produced in the liver.

Hydrocortisone--a possible physiological regulator of human granulopoiesis

The effect of hydrocortisone (HC) on the formation of granulocyte-macrophage (GM) colonies was assessed in vitro in cultures of normal human bone marrow. Subphysiological concentrations (less than or equal to 10(-8) mol/l) of HC had no impact on GM colony formation, but at physiological and therapeutic levels (10(-7) mol/l-10(-5) mol/l) the hormone stimulated the production of an increased number of colonies. By contrast, physiological concentrations of progesterone (10(-9) mol/l-10(-7) mol/l) were without effect and even at 10(-6) mol/l there was no influence of progesterone alone on GM colony formation. However, progesterone at 10(-6) mol/l inhibited the stimulant effect of HC to a degree which was related inversely to the concentration of HC and the duration of the culture interval. The data from this study suggest that the neutrophilia which accompanies glucocorticosteroid therapy is matched by an increase in the production of granulocytes and that HC may play a rôle, which is mediated by steroid receptors, in the physiological regulation of human granulopoiesis.

Research methods workshop for health professionals in Sierra Leone: an international collaborative project

In 1979 a research methods seminar for health professionals in Sierra Leone was conducted as part of an international medical education collaborative project between Sierra Leone, Canada, the United Kingdom and the European Economic Community. The aim of the seminar was to promote research and inquiry into national health problems. Planning and administration was conducted by Sierra Leone with Canada providing teaching materials and four tutors. Twenty-seven participants attended the seminar. Participants prepared research protocols prior to the seminar which they developed and refined during the 7 days of the workshop. Using a problem-based method Sierra Leonean health problems were used as the focus to teach epidemiological and biostatistical methods. The seminar was evaluated on the basis of a number of parameters. There was 89% attendance at the nineteen sessions. Twenty-one of the twenty-seven participants presented protocols at the final evaluation session. Self-evaluation of protocols showed improvement in most aspects but particularly in research design, methods of data gathering, analysis and ethical aspects. An opinion survey of participants showed the seminar to be viewed positively. Twelve months later six participants had submitted their protocols for funding of whom four were successful. A further seminar has been conducted in which Sierra Leoneans participated as co-tutors. This seminar format has been presented as an effective means of providing professional assistance from one country to another.

Effects of preschool screening for vision and hearing on prevalence of vision and hearing problems 6-12 months later

In order to determine whether children screened 6-12 months previously for vision and hearing had fewer vision and hearing problems than a non-screened cohort, a trained nurse-tester examined 763 screened and 743 non-screened kindergarten children matched for age, sex, and socioeconomic status. The screened cohort had significantly fewer vision problems (10%) than the unscreened (15%). The difference for moderately severe problems (visual activity 20/50 or worse) was also significant. 58% more screened than unscreened children were wearing glasses. The screened cohort had more hearing problems (16.8%) than the non-screened group (14%), but the difference was not statistically significant. There was a marked seasonal variation in prevalence of hearing problems, the frequency in November and December being twice that in April, presumably a result of increased frequency of upper respiratory problems in those months. Preschool hearing screening, unlike vision screening, is not associated with improved end results.

Effect of vitamin E therapy on blood coagulation tests in newborn infants

A double-blind randomized trial of vitamin E therapy was conducted in premature infants whose birth weight was less than 1,500 gm. Treated infants received 25 mg of vitamin E daily by mouth for the first six weeks of life. Detailed studies of plasma coagulation factors were performed prior to therapy and at days 7 and 42. None of the factors differed significantly between the treated and control groups. Although vitamin E therapy has been reported to affect the blood levels of vitamin K dependent coagulation factors, no such effect was noted in this group of premature infants.