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PubMed1994

An epidemiological study of hand eczema. I. Prevalence and cumulative prevalence among hairdressers compared with a control group of teachers.

The aim of this cross-sectional study was to estimate the prevalence of dermatitis of the hands and/or forearms among hairdressers compared with a control group of elementary school teachers. Questionnaires were sent to 818 hairdressers and 816 teachers. The response rates were 83% and 65%, respectively. The mean age for those completing the questionnaire, was 28 years (range: 17-71) for the hairdressers and 45 years (range: 20-70) for the teachers. The mean number of months employed in these occupations was 105 (range: 1-672) and 186 (range: 0-516), respectively. Forty-two per cent of the hairdressers and 23% of the teachers suffered or had been suffering from exanthema of the hands and/or forearms. Sixty-one and 15%, respectively, related the skin disease to work.

Adolescent↗
PubMed1980

HLA antigens in patients with giant cell arteritis, compared with two control groups of different ages.

The prevalence of 39 HLA antigens of series A, B and C was determined in 63 patients with Giant cell arteritis. In 44 patients the diagnosis was established by means of temporal artery biopsy and in 19 it was based on clinical criteria. The prevalence of the antigens was compared with that in two control groups of different ages. No significantly increased antigen prevalence was seen in our patients, as compared with controls. There were no differences in the prevalence of HLA antigens between groups of patients with different clinical forms of GCA. Nor was any difference in the prevalence of HLA antigens found between younger and older healthy individuals.

Age Factors↗
PubMed1993

Serum FSH bioactivity and response to acute gonadotrophin releasing hormone (GnRH) agonist stimulation in patients with polycystic ovary syndrome (PCOS) as compared to control groups.

OBJECTIVE: We evaluated the biological activity of FSH in the serum of women with polycystic ovary syndrome before and after acute administration of a GnRH agonist as compared to control groups. DESIGN: FSH, oestradiol and androstenedione response to buserelin (100 micrograms s.c.) comparing seven polycystic ovary patients, six idiopathic hirsute women, 11 normal women in the follicular phase and nine normal men. MEASUREMENTS: Rat granulosa cell aromatase bioassay in the presence or absence of polyethyleneglycol (PEG) pretreated 2% serum. Serum biological FSH (B-FSH), immunological FSH (I-FSH) and B/I ratio at times 0, 1, 2, 3, 4, 8, 12 and 24 hours. Serum androstenedione and oestradiol at times 0 and 24 hours. RESULTS: Human gonadotrophin-free (oral contraceptive user and after FSH immunoabsorption) and PEG-pretreated serum increases the aromatase activity in response to increasing doses of purified FSH. The maximum enzymatic activity is however higher with 2% serum than with 4% serum. The amplitude of the B-FSH response to the GnRH agonist is markedly decreased in the polycystic group as compared to the group of normal women. There is also a small decrease in the I-FSH response in the polycystic women. When compared to that of normal women, the area under the curve in the polycystic ovary patients is reduced by 71% for B-FSH (P < 0.01) and by 23% for I-FSH (P < 0.05). The B-FSH and I-FSH responses in men are very small. After an initial decrease the B/I ratio returns to baseline level in normal women but remains low in the other groups. At time 24 hours, there is no significant change in the serum concentration of androstenedione but serum oestradiol, the baseline of which is significantly higher in the polycystic patients than in normal women, is also significantly higher at 24 hours (P < 0.05) in response to the pharmacological release of FSH. CONCLUSION: The gonadotrophin-free and PEG-pretreated human serum has an inherent stimulatory effect on the rat granulosa aromatase bioassay with a higher activity at 2% serum. Acute GnRH agonist stimulation reveals a deficiency in the FSH response in polycystic ovary patients. The greater deficit in B-FSH than in I-FSH would indicate a possible modification in the FSH isoforms in this syndrome. The meaning of this observation for the understanding of the physiopathology of the polycystic ovary syndrome remains to be evaluated.

Adolescent↗
PubMed1995

Self-reported satisfaction with life and physical health in long-term cancer survivors and a matched control group.

The response to two validated questions assessing self-reported satisfaction with life and physical health were compared between 204 long-term head and neck cancer survivors from a randomised radiotherapy trial and 766 matched controls. The control group, participants in a large population health survey in a county in the middle of Norway, was matched to the patients with regard to age, gender, marital status/family type and education. Compared with the controls, the patients reported significantly lower satisfaction with life and physical health. Sixty-four per cent of the patients were satisfied with life and 44% felt strong and healthy while the percentages of the controls were 82% and 52%, respectively. Clinical and sociodemographic variables were poor predictors of the patients' responses. Clinicians must be aware of the psychosocial morbidity in the growing population of cured cancer patients, and intervention studies are needed in patients at risk, in order to determine whether this morbidity can be prevented, reduced, or treated.

Adult↗
PubMed1991

Prognostic value of morphometry and DNA flow-cytometry features of invasive breast cancers detected by population screening: comparison with control group of hospital patients.

Using the prognostic value of morphometric and flow-cytometric features, a group of patients with invasive breast cancers detected with population screening (PS, n = 70) has been evaluated and compared with a random control group in 2 hospitals (H group, n = 225) diagnosed in the same period. The results show that the PS patients had smaller tumors, less positive lymph nodes, better differentiated tumors with a lower mitotic activity index (MAI) and lower values of the morphometric prognostic index (MPI). Furthermore, the women more frequently had diploid tumors and tumors with small nuclei. The second purpose was to evaluate whether quantitative microscopical features, in comparison with other prognostic features such as size of primary tumor, nodal status and histologic grade, are as strong prognosticators in PS tumors as in H-detected breast cancers. In comparison with H tumors, morphometric and flow-cytometric features, as well as tumor size, had the same prognostic value for the PS tumors. In contrast, nodal status was not significant within the PS group, and the same phenomenon was found in a subgroup of H patients with similar sized tumors. Of all quantitative microscopical features (MPI, MAI, mean nuclear area (MNA) and DNA Index (DI], the MAI had the strongest prognostic value. DI showed additional prognostic value to the MAI for patients with small tumors and with small tumor-cell nuclei, because a diploid pattern in these cases (this combination occurred in 21 patients of the total group = 30%) was correlated with a 95% 10-year survival rate. Histologic grade, although significant within the large H group, was of no prognostic value within the PS group, and also not as in the H sub-group with small tumors. It is concluded from morphometric and DNA flow-cytometric criteria that these prognostic features in invasive breast cancers detected by PS were all more favorable than in randomly detected hospital breast cancers. This may account for the reported better survival rate of PS patients. Furthermore, the prognosis of patients with small invasive breast cancers detected by population screening can be more accurately deduced by quantitative microscopical features than by axillary-lymph-node status.

Aged↗
PubMed2000

Placebo control groups in randomized treatment trials: a statistician's perspective.

Because a statistical tie between standard treatment and an innovation is uninterpretable, most trials intended to demonstrate efficacy of innovations in psychopharmacology employ a placebo control group, despite the existence of standard medications for many disorders. In this review I consider the statistical issues that inform the ethics of the decision to use a placebo condition and make the following points: 1) the investigator is relying on the assumption that the effects of delayed standard treatment are neither long-lasting nor harmful; 2) the usual practice of truncating follow-up when a patient ceases to adhere to a study treatment makes it difficult to empirically test that assumption; 3) placebo control trials often suffer from methodological weaknesses (including nonrandom truncation) that reduce their inferential power; 4) these subtleties place a substantial burden on the informed consent process; 5) alternative designs are available but not well explored, due to the dominant role of "regulatory" trial methodology; and 6) researchers should consider other goals besides helping to introduce another treatment that improves on placebos but not the standard treatment.

Antipsychotic Agents↗
PubMed1999

Interpersonal violence in a "normal" low-income control group.

This paper examines the rates of interpersonal violence and trauma reported in a sample of 98 urban, low-income women, predominantly Latina or African-American descent constituting a "normal" control group for a larger study on drug abuse and violence. This sample was recruited from the obstetrics-gynecology outpatient clinic at St. Luke's-Roosevelt Hospital Center in New York City and carefully screened for the absence of any DSM-IV Axis I psychopathology including major mood disorders, anxiety, psychotic, alcohol and substance use disorders. Consistent with the literature, our sample exhibited rates of interpersonal violence and trauma markedly above estimates for women nationwide; compared to such national figures, our sample was at higher risk for experiencing childhood sexual abuse, childhood physical abuse, and partner violence. Almost one-quarter of our sample met diagnostic criteria for lifetime post-traumatic stress disorder. Ten to twenty percent of our sample reported other kinds of trauma, such as witnessing a murder, seeing violence between her parents, or being homeless. Interestingly, women in our sample were more likely than women nationwide to tell someone else of their abuse or trauma; it may be that disclosure of such events to a supportive person has protected these women to a certain extent from some of the longer-term potential effects of such negative experiences. The data collected in this study underscore the need for mental health and medical professionals to be sensitive to the high prevalence of certain kinds of traumatic and violent experiences in the lives of inner-city, low-income, minority women.

Adult↗
PubMed2006

Classification of Centers for Disease Control Group Eugonic Fermenter (EF)-4a and EF-4b as Neisseria animaloris sp. nov. and Neisseria zoodegmatis sp. nov., respectively.

A polyphasic taxonomic study was performed on isolates classified as Centers for Disease Control Group Eugonic Fermenter (EF)-4a and EF-4b. Comparative 16S rRNA gene sequence analysis confirmed that group EF-4a and EF-4b belong to the genus Neisseria with Neisseria canis and Neisseria dentiae as the nearest phylogenetic neighbours. DNA-DNA hybridizations and biochemical analyses demonstrated that isolates of group EF-4a and EF-4b represent two novel species within this sublineage of the genus Neisseria. Based on the results of the present study, isolates of group EF-4a and EF-4b are classified as Neisseria animaloris sp. nov. (type strain LMG 23011(T)=NCTC 12228(T)) and Neisseria zoodegmatis sp. nov. (type strain LMG 23012(T)=NCTC 12230(T)), respectively.

Animals↗
PubMed1978

Viscosity of duodenal juice examined in patients with excretory pancreas insufficiency by the pancreocymin secretin test compared to a control group and patients with cholelithiasis.

The viscosity of duodenal juice obtained during the pancreocymin secretin test from patients with excretory pancreas insufficiency was significantly higher compared to the viscosity of duodenal secretions from a control group or from patients with gall bladder stones. Since the viscosity was inversely related to the total volume as well as the bicarbonate and trypsin concentrations, it is concluded that the increased viscosity is due to a reduction in the secretory activity of the pancreas. The viscosity measurements found for patients with cholelithiasis reflects merely the higher viscosity of the gall bladder bile.

Adult↗
PubMedDate not supplied

[ECG changes in spondylarthritis ankylopoietica in comparison with a healthy control group].

ECG from 150 patients with clinically and radiologically established ankylosing spondylitis were compared with those from a healthy age and sex matched group. The reported frequency of atrioventricular conduction defects (3-15%) was confirmed (4.6%). These and other pathological ECG changes were also found in the control group. No significant statistical difference in frequency was found. The refore doubt remains whether the pathological changes of the ECG can be attributed to ankylosing spondylitis.

Adult↗
PubMedDate not supplied

The control group dilemma in clinical research: applications for psychosocial and behavioral medicine trials.

OBJECTIVE: Clinical research on psychosocial and behavioral medicine interventions has burgeoned in the past two decades, so much so that sole reliance on standard no-treatment control conditions may no longer be appropriate or feasible. We discuss the ethical, theoretical, scientific, and statistical considerations that shape current clinical outcomes research for psychosocial and behavioral medicine interventions. METHOD AND RESULTS: Secondary analysis of a psychosocial randomized trial (N = 127) illustrates some of these points. CONCLUSIONS: A new design for randomized clinical trials is described that does not require a no-treatment control group, and that reveals dose-response relationships between interventions and treatment outcomes.

Behavior Therapy↗
PubMed2006

A randomized, controlled trial of the effectiveness of cognitive-behavioral therapy and sertraline versus a waitlist control group for anxiety disorders in older adults.

OBJECTIVE: This study is the first to investigate the relative effectiveness of cognitive-behavioral therapy (CBT) compared with a selective serotonin reuptake inhibitor (SSRI; sertraline) in a randomized, controlled trial on the treatment of anxiety disorders in older adults. METHOD: Eighty-four patients 60 years of age and over with a principal diagnosis of generalized anxiety disorder, panic disorder, agoraphobia, or social phobia were randomly assigned to one of three conditions: 15 sessions of CBT, pharmacologic treatment with an SSRI (sertraline; maximum dosage 150 mg), or a waitlist control group. Participants completed measures of primary outcome (anxiety) and coexistent worry and depressive symptoms at baseline, posttreatment, and at three-month follow up. RESULTS: Attrition rates were high in both treatment groups. Consequently, findings are based on a relatively small sample of completers (N = 52). Although both CBT and sertraline led to significant improvement in anxiety, worry, and depressive symptoms both at posttreatment and at three-month follow up, sertraline showed superior results on worry symptoms. Effect size estimates for CBT were in the small to medium range both at posttreatment (mean d = 0.42) and at three-month follow up (mean d = 0.35), whereas effect sizes for sertraline fell into the large range (posttreatment mean d = 0.94 and three-month follow up mean d = 1.02). The waitlist condition showed virtually no effects (posttreatment mean d = .03). CONCLUSIONS: Our findings strongly suggest that the pharmacologic treatment of late-life anxiety with SSRIs has not been given the proper attention in research to date.

Aged↗
PubMed1997

Comparative analysis of apo(a) gene alleles: distribution of pentanucleotide repeats in position -1373 and C/T transition in position +93 among patients with myocardial infarction and a control group in St. Petersburg, Russia.

To evaluate whether polymorphisms in the 5' region of the apolipoprotein(a) gene alter the risk for myocardial infarction, 289 Russian male patients with myocardial infarction (MI) and 284 subjects in a control group were investigated regarding the distribution of pentanucleotide repeats (PNRs) at position -1373 and a C/T transition at position +93. For detection of the C/T (+93) allele, we developed a rapid, nonisotopic method by mismatch PCR-mediated site-directed mutagenesis and restriction enzyme digestion. We observed significant differences in prevailing alleles with over eight (TTTTA) repeats among MI patients, including those with MI younger than 55 years of age. We observed the prevalence of the T (+93) allele in children without a family history of CHD compared to young MI patients. These findings support the notion that PNR alleles with over eight (TTTTA) repeats may play a pathogenic role, and the T (+93) allele may have a protective effect for the inherited predisposition to heart disease.

Adolescent↗
PubMed2005

Reassessment of the diagnostic value of histology in patients with GERD, using multiple biopsy sites and an appropriate control group.

BACKGROUND: Histology is generally considered as a tool of limited value in the diagnosis of gastro-esophageal reflux disease (GERD). AIM: To reevaluate the diagnostic role of histological alterations in GERD, using multiple biopsy sites and an appropriate control group. METHODS: We studied 135 patients with typical and atypical symptoms of GERD. They underwent upper GI endoscopy and Los Angeles classification was used for grading cases with mucosal breaks. Biopsies were taken at the Z-line, 2 and 4 cm above it. Microscopic esophagitis was identified by necrosis/erosion, neutrophil/eosinophil intraepithelial infiltration, basal cell hyperplasia, elongation of papillae, dilation of intercellular spaces and a score (range: 0-2) was given for each lesion. Twenty-four-hour esophageal pH monitoring was performed in each patient. Twenty subjects without reflux symptoms, and with normal endoscopy and pH testing were considered as controls. RESULTS: Histological alterations were found in 100 of 119 GERD patients (84%) and in 3 of 20 controls (15%) with a significant difference (p < 0.00001). Histology was abnormal in 96% of patients with erosive esophagitis and in 76% of patients with nonerosive reflux disease (NERD). The sum of scores of microscopic lesions found in all biopsy sites ranged from 0 to 22 and we identified a cut-off value (score 2) that distinguished efficiently controls from GERD patients. CONCLUSIONS: In contrast with previous reports on the marginal role of histology in patients with GERD, our study shows that this technique can be a useful diagnostic tool, particularly in patients with NERD, when biopsies are taken at two sites including Z-line and 2 cm above it.

Adult↗
PubMed1997

Anal cytological abnormalities and anal HPV infection in men with Centers for Disease Control group IV HIV disease.

OBJECTIVE: To characterise risk factors for abnormal and cytology and anal human papilloma virus (HPV) infection in homosexual/bisexual men with advanced HIV related immunosuppression. DESIGN: Cross sectional study of men with Centers for Disease Control group IV HIV disease. SETTING: The University of California San Francisco, AIDS Clinic. PATIENTS: 129 homosexual or bisexual men with group IV HIV disease. METHODS: A questionnaire was administered detailing tobacco, alcohol and recreational drug use, medical history, and sexual practices. Anal swabs for cytology and HPV studies were obtained, as was blood for CD4 levels. MAIN OUTCOME MEASURES: Abnormal anal cytology and anal HPV infection. RESULTS: Abnormal anal cytology was detected in 39% of subjects and anal HPV infection in 93% as measured by polymerase chain reaction (PCR). Risk factors for abnormal cytology in multivariate analysis included HPV 16/18 infection (measured by PCR, RR = 2.1, 95% CI = 1.2-3.5) and intravenous drug use (RR = 1.8, 95% CI = 1.2-2.7). Infection with HPV 6/11 also had significantly elevated RRs in a separate model. Cigarette smoking, alcohol use, recreational drug use, and low CD4 level were associated with abnormal anal cytology in univariate analysis, as was infection with multiple HPV types and high levels of hybrid capture group B viral DNA. CONCLUSIONS: Anal cytological abnormalities and HPV infection are common among homosexual/bisexual men with group IV HIV disease. In this study population, the main risk factors for abnormal cytology were HPV infection and intravenous drug use.

Adult↗
PubMed1999

Comparison of tear lactate dehydrogenase activities of different types of contact lens wearers and normal control group.

PURPOSE: The purpose of this study was to compare the lactate dehydrogenase (LDH) activities in the tears of patients wearing different types of contact lenses with each other and to individuals who have never worn contact lenses (controls). METHODS: Tear LDH activities were determined in 13 normal subjects who had never worn contact lenses, 12 daily wear and ten extended wear soft contact lens wearers, and 14 daily wear and eight extended wear rigid gas permeable (RGP) contact lens wearers(Dk125). Tear samples were collected from all subjects at the same time of day from the inferior meniscus by using a microcapillary tube. The measurements were determined using a Sigma diagnostic LDH reagent and a spectrophotometer. RESULTS: There was no statistically significant difference in the LDH activities between soft and RGP contact lenses--used either as daily or extended wear--when compared with each other. However, individuals wearing extended wear soft contact lenses had significantly higher tear LDH activities than the control group. CONCLUSION: Tear LDH activity may be a useful method in evaluating the physiologic response of extended soft contact lens wear.

Adolescent↗
PubMed2001

Quantitative electroencephalography in Alzheimer's disease: comparison with a control group, population norms and mental status.

OBJECTIVE: Given that quantitative electroencephalography (EEG) has repeatedly shown excessive slow wave activity in dementia of the Alzheimer type (DAT) that increases with disease progression, we assessed the clinical utility of this tool by comparing various approaches used to assess slowing. DESIGN: Cross-sectional study comparing quantitative EEG data from patients with DAT with normative data from an elderly control group and from EEG norms derived from a large population. PARTICIPANTS: 35 subjects diagnosed with probable DAT and 30 elderly controls. OUTCOME MEASURE: EEG recorded from 21 scalp sites of each patient and elderly control during vigilance-controlled, eyes-closed, resting conditions was spectrally analyzed to yield measures of absolute and relative power in delta, theta, alpha and beta bands and indices of mean alpha band and total band frequency. RESULTS: Group comparisons of raw or age-regressed z-score population normative values yielded different profiles with respect to direction of frequency band changes, regional topography and clinical rating correlations, but both procedures evidenced overall patterns of EEG slowing in DAT. However, both methodologies yielded only modest (75%) classification rates. CONCLUSION: Quantitative EEG remains a valuable research tool but, as yet, an unproven diagnostic tool, for DAT.

Aged↗