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At least 307 records · Page 17Linked to original sources
PubMed2004

A note on testing for homogeneity among effect sizes sharing a common control group.

L. V. Hedges and I. Olkin (1985) presented a statistic to test for homogeneity among correlated effect sizes and L. J. Gleser and I. Olkin (1994) presented a large-sample approximation to the covariance matrix of the correlated effect sizes. This article presents a more exact expression for this covariance matrix, assuming normally distributed data but not large samples, for the situation where effect sizes are correlated because a single control group was compared with more than one treatment group. After the correlation between effect sizes has been estimated, the standard Q statistic for correlated effect sizes can be used to test for homogeneity. This method is illustrated using results from schizophrenia research.

Humans↗
PubMedDate not supplied

[Medicamentous obstetric analgesia with pentazocine in comparison with an untreated control group].

In order to establish whether a powerful analgesic such as pentazocine administered during birth may damage the child or have negative influence on the course of birth, the course of delivery was studied in 40 patients, 20 of whom were given a single dose of 30 mg pentazocine administered intramuscularly. There were no differences in duration of birth, CTG, blood gases post partum, or Apgar scores as compared to the untreated control group. As regards the pharmacokinetics, the serum pentazocine levels of the gravidae corresponded to those found in non-pregnant subjects; the levels found in blood from umbilical cords and new-borns were at the lower limit of detectability. Almost all of the gravidae described the obstetric analgesia as good or adequate. The principal side effect, mentioned by one-third of the pentazocine group, was slight fatigue. As regards the newborns, the fetal outcome in the two groups was the same.

Adult↗
PubMed2002

Pulsatile blood pressure component as predictor of mortality in hypertension: a meta-analysis of clinical trial control groups.

OBJECTIVE: Although current guidelines rest exclusively on the measurement of systolic and diastolic blood pressures, the arterial pressure wave is more precisely described as consisting of a pulsatile (pulse pressure) and a steady (mean pressure) component. This study explored the independent roles of pulse pressure and mean pressure as predictors of mortality in a wide range of patients with hypertension. DESIGN AND METHODS: This meta-analysis, based on individual patient data, has combined results from the control groups of seven randomized clinical trials conducted in patients with systolo-diastolic or isolated systolic hypertension. The relative hazard rates associated with pulse pressure and mean pressure were calculated using Cox's proportional hazard regression models with stratification for the seven trials and with adjustment for sex, age, smoking and the other pressure. RESULTS: A 10 mmHg wider pulse pressure at baseline, which corresponds to approximately one-half of its standard deviation, was independently associated with an increase in risk by 6% for total mortality (P = 0.001), 7% for cardiovascular mortality (P = 0.01), and 7% for fatal coronary accidents (P = 0.03). The corresponding increase in risk of fatal stroke was similar (+6%, P = 0.27) but there were too few strokes to reach statistical significance. In similar analyses, mean pressure was not identified as an independent predictor of these outcomes. Significant interactions of pulse pressure or mean pressure with age suggested that the prognostic power of pulse pressure for fatal stroke was more important at higher age (P = 0.04), whereas the prognostic power of mean pressure for coronary mortality was greatest in the young (P = 0.01). CONCLUSIONS: In hypertensive patients pulse pressure, not mean pressure, is associated with an increased risk of fatal events. This appears to be true in a broad range of patients with hypertension.

Age Factors↗
PubMed1995

Red-cell and serum folate levels in depressed inpatients who commit violent suicide: a comparison with control groups.

There has been some discussion in the recent literature regarding the possible relationship between peripheral levels of folate and serotonin deficiency in the CNS. At the same time, such a serotonin deficiency has been implicated in the biology of suicidal behavior. Thus, decreased peripheral folate levels may be expected in patients who commit violent suicide. In this study, the red-cell and serum folate levels in nine persons who later committed suicide are compared with those in age- and sex-matched control groups. A one-way analysis of variance showed no significant difference between the groups.

Adult↗
PubMed2006

Subjective quality of life of outpatients with diabetes: comparison with family caregivers' impressions and control group.

BACKGROUND: There is a paucity of studies on comparison of quality of life (QOL) of type-1 and type-2 diabetes patients, and the impact of family caregivers' impressions on the QOL of patients. OBJECTIVES: To assess the subjective QOL of Sudanese diabetics using the WHOQOL-Bref, compared with a general population sample; examine caregiver-patient concordance; and assess the variables that impact on QOL. METHOD: The responses of 105 outpatients with type-1 diabetes and 136 with type-2 diabetes were compared with their family caregivers' impressions and 139 general population subjects. RESULTS: Patients were predominantly dissatisfied with their life circumstances. Type-1 diabetics had significantly lowest QOL scores, while the control group had highest scores. Having additional medical problems; having diminished sexual desire; and being young, unemployed and single were associated with poor QOL, but illness duration was not. Type-2 diabetics had lesser concordance with caregivers. The only predictor of patients' QOL was the caregivers' impression of patients' QOL. CONCLUSIONS: Caregivers' impression of patients' QOL impacted on outcome. Caregiver education is, therefore, important. The factors associated with QOL indicate a group that needs focused attention. The good QOL for type-2 and nonsignificance of illness duration encourage therapeutic optimism.

Adolescent↗
PubMed2005

Outcome of 60 neonates who had ARED flow prenatally compared with a matched control group of appropriate-for-gestational age preterm neonates.

OBJECTIVE: To describe the course and outcome of fetuses with absent or reversed end-diastolic (ARED) flow in the umbilical artery (UA) and to examine the influence of prematurity according to gestational age at delivery. METHODS: Sixty pregnancies complicated by ARED flow in the UA were monitored by repeat Doppler measurements of arterial and venous vessels, non-stress tests (cardiotocogram (CTG)) and maternal investigations, and were delivered between 24 and 34 weeks. Fetal outcome was investigated and compared to a control group of appropriate-for-gestational age (AGA) preterm neonates, matched for gestational age. Mortality, birth weight, Apgar scores, postnatal cord arterial pH and need for ventilation were all recorded, as were cases of respiratory distress syndrome, bronchopulmonary dysplasia, persistent ductus arteriosus, necrotizing enterocolitis, intraventricular hemorrhage, periventricular leukomalacia, abnormal neurological findings and those requiring surgical intervention. Additionally, the group of fetuses with ARED flow was divided into three subgroups of different degrees of prematurity (delivery between 24 + 0 and 28 + 6 weeks, delivery between 29 + 0 and 31 + 6 weeks, and delivery after 32 weeks) and compared according to the above parameters. RESULTS: Pre- or postnatal death occurred in 16 cases. Comparing the 44 (61%) that were born alive with the AGA neonates, significant differences were found in birth weight (P < 0.001), arterial pH value (P < 0.001), bronchopulmonary dysplasia (P = 0.002) and intestinal complications (P < 0.01). Prematurity-related complications were: need for ventilation (P = 0.001), respiratory distress syndrome (P < 0.0001), periventricular leukomalacia (P = 0.002) and pathological neurological testing (P = 0.005). CONCLUSIONS: Neonates displaying ARED flow before birth are growth restricted, acidemic at delivery and are at high risk of developing bronchopulmonary dysplasia and intestinal complications. While perinatal mortality seems to be related to abnormal fetal Doppler velocimetry, age at delivery has a significant impact on short-term morbidity. After 32 weeks, morbidity is low and delivery should be considered. It could be speculated from our data that prolongation of pregnancy with Doppler velocimetry monitoring could help to reduce morbidity, although prolongation remains limited in most cases.

Birth Weight↗
PubMed2003

Reduction or elimination of postoperative pain medication after mastectomy through use of a temporarily placed local anesthetic pump vs. control group.

OBJECTIVE: We evaluated the efficacy of a temporarily placed porous catheter with continuous application of a local anaesthetic(ON-Q( by l-Flow-Corp., Lake Forest, CA, USA) post mastectomy vs. patients without this device regarding postoperative need for opioid medication. MATERIAL AND METHODS: At Fayette Medical Center, Alabama, a retrospective evaluation of all consecutive mastectomies (n = 49) within a five-year-period from 1/1997-12/2001 and statistical analysis regarding postoperative need for opioids was performed. The ON-Q pain management pump with continuous 0.25% Sensorcaine (Bupivacaine and Epinephrine) application for about 72 h (n- 22) was compared vs. a control group without pain management pump (n- 27). RESULTS: There were no statistical significant differences regarding patient demographics in both groups. Patients in the ON-Q group with no need of postoperative opioid pain medication were: 18.2 vs. 3.7 % (P - 0.1), no need for opioids after postoperative day 1: 68.2% vs. 11.1 % (P 0.001), total opioids usage in dose equivalents (DE): 1.25 vs. 3.36 DE (-62.8%) (P-0.016), opioids usage postoperative day 1: 0.65 vs. 1.82 DE (-64.6%) (P - 0.016),opioids usage postoperative day 2: 0.24 vs. 0.75 DE (-68.4%)(P - 0.011). The length of stay in hospital was 2.35 vs. 2.93 days(n.s.), and postoperative stay in PACU: 384 vs. 43.3 min (n. s.).OR time for placement of catheter and pump is only slightly increased. No complications occurred. CONCLUSION: Use of an ON-Q pain management pump could significantly reduce or even eliminate postoperative need for opioids analgesics.

Aged↗
PubMed1994

Cobalt excretion in urine: results of a study on workers producing diamond grinding tools and on a control group.

A study was carried out on cobalt (Co) excretion in the urine of 12 workers exposed to known cobalt concentrations in the stone cutting diamond wheel production and in six volunteers: four of these were exposed in the same work environment for a whole workshift and the other two were exposed to cobalt in a cabin under experimental conditions. The kinetics of the urinary excretion was multiphase: (i) a first stage of rapid elimination (T 1/2' = 43.9 h); (ii) a second phase of slower elimination (T 1/2'' = 10 days); (iii) a longer period of retention, of the order of years, in subjects with higher exposure. In the control group (4 subjects), the excretion proved to be much faster in the first stage (T 1/2' = 20 h). The different behaviour of the two groups could be related to the different body burden, of cobalt and/or to the possibility of different kinetics induced by continuous exposure to the metal. Moreover, 3 weeks after the removal of the workers from exposure the urinary cobalt concentrations were not within the normal limits of CoU for the general population, (even for workers exposed to cobalt levels of the same order as the TLV). The increase of CoU concentrations in the first 3 h after the end of exposure, stresses the problem of when urine samples for biological monitoring of the workers should be collected. The present study confirms the utility of CoU in discriminating between exposed and non-exposed subjects as well as in assessing high and low level exposure.

Adult↗
PubMed2004

Treatment of joint pain and joint noises associated with a recent TMJ internal derangement: a comparison of an anterior repositioning splint, a full-arch maxillary stabilization splint, and an untreated control group.

Pain and joint noises associated with temporomandibular joint (TMJ) internal derangement are often treated by using an intra-oral splint. This study evaluated whether an anterior repositioning splint (AR splint) could be more effective in the treatment of these symptoms than a full-arch maxillary stabilization splint (FAMS splint), because of its capability to re-establish immediately the normal condyle/disk relationship. The authors treated 40 patients (average age 16.8; range 8.0-24.0) with confirmed internal derangement, joint pain, and joint noises in at least one TMJ for at least two months, with AR splint (20 subjects) or FAMS splint (20 subjects); 10 untreated patients comprised the control group. Joint noise, joint pain, and the intensity of pain were assessed using a visual analogic scale (VAS), and the pain was characterized (i.e., constant or chewing/biting pain) and evaluated monthly for eight months. Significantly fewer AR splint patients experienced pain after four months of treatment. A significantly lower intensity of pain was experienced by the AR splint patients after two months of treatment. Significantly fewer AR splint patients experienced chewing/biting pain after eight months of treatment. The frequency of joint noises decreased over time, with no significant differences between the groups. In conclusion, the AR splint seems to be more effective in decreasing pain, but it seems to make no difference in the treatment of joint noises.

Adolescent↗
PubMedDate not supplied

Circadian study on serum gastrin in patients with duodenal ulcers and in a control group.

Two groups of subjects (one consisting of fourteen apparently healthy subjects, the other of fourteen patients with peptic ulcers) were kept for a least 7 days on the same living schedule (nocturnal sleep for 22(00) to 05(00) and meals standardized at 08(00)-08(30), 12(00)-12(30), 17(30)-18(00)). During 24 hors, samples of venous blood were obtained from each subject every 4 hours for the serum gastrin radioimmunoassay. The results were analyzed by mean cosinor method. The control group has a statistically significant circadian rhythm, while we were not able to detect a circadian rhythm in the patients with duodenal ulcers. The daily mean of serum gastrin levels appears to be significantly reduced in the ulcer group.

Adolescent↗
PubMed2004

Cardiovascular and respiratory status in mechanically ventilated asphyxiated term infants: comparison between hypothermic and control group.

OBJECTIVE: To evaluate cardiorespiratory changes in hypothermic asphyxiated ventilated infants compared with controls. STUDY DESIGN: Retrospective chart analysis with historical controls. Cardiorespiratory status of 10 asphyxiated newborns in hypothermia (H) (32 degrees-34 degrees C) (H group) was compared with that one of 11 asphyxiated newborns [control group, (C group)]. RESULTS: 3/10 patients in H group needed an increased mean tidal volume (from 5.8 to 8 ml/Kg) during hypothermia when temperature reached a value of 32 degrees C, to maintain adequate gas exchange. Length of mechanical ventilation was similar in the two groups (H=5.4+/-4.4 vs C=2.8+/-2.7 days, p=ns). Heart rate, similar at the baseline (H group: 129+/-11 beats/min; C group: 129+/-12 beats/min), dropped to an average of 102+/-10 beats/min (p<0.05) during cooling in H group, while it remained stable in C group. Mean arterial blood pressure, comparable at birth, increased by a median of 8 mmHg during hypothermia (p=ns). CONCLUSIONS: Hypothermia induces mild changes in cardiovascular status and in lung mechanics.

Asphyxia Neonatorum↗
PubMed1987

Antibodies to Epstein-Barr virus-specific DNase in patients with nasopharyngeal carcinoma and control groups.

Serum samples from 154 patients with nasopharyngeal carcinoma (NPC), 374 with other cancers, 1,000 normal controls from Government Employees' Clinic Center (GECC), and 3,642 individuals of various ethnic-dialect groups living in high-risk areas for NPC were collected and the concentration of antibodies to Epstein-Barr virus (EBV)-specific DNase activity was determined. Taking a serum sample where 1 ml will neutralize two or more units of the DNase activity as positive, 2-4 units as low level, 4-6 units as medium level, and more than 6 units as a high level of antibody, 90.3% of the NPC patients contained significant amounts of antibodies to EBV-specific DNase activity and most of those had high levels of the antibody. In contrast, only 11% of sera from patients with cancers other than NPC contained antibodies to EBV-specific DNase activity, and high levels were very rare (2.1%). The difference in positive rates between these two groups is highly significant according to the chi 2 test (P less than 0.001). The positive rate of this antibody in the control group (GECC) was 5.3% with 0.0%, 0.8%, and 4.5% having high, medium, and low levels of antibodies, respectively. Again, the difference in positive rates between the GECC group and the NPC group is statistically significant (P less than 0.001). Taken separately, the positive rates of anti-EBV DNase activity in the three high-risk groups were 11.7%, 13.0%, and 13.1%. No significant difference in age distribution for the levels of this antibody was observed in the control GECC group or the three high-risk groups. However, the positive rates of the three high-risk groups are more than twice those of the GECC group (11.7% approximately 13.1% vs 5.3%). This ratio coincides with the ratio of the probability of developing NPC in high-risk groups compared to that of the GECC group (also more than two times). The significance of this coincidence is discussed.

Age Factors↗
PubMed2001

Erectile dysfunction in a primary care setting: results of an observational, no-control-group, prospective study with sildenafil under routine conditions of use.

In order to assess the effectiveness of sildenafil under routine conditions of use in primary care settings and to evaluate its impact on patient's life satisfaction and partner's satisfaction with treatment for erectile dysfunction (ED), an open, multicentre, observational, prospective study was designed in which 2816 patients were treated with sildenafil for at least 10 weeks. Effectiveness was assessed using the International Index of Erectile Dysfunction (IIEF), life satisfaction was measured with 'Life-satisfaction Check List' (LISAT 8), and EDITS was optionally used to assess the partner's satisfaction with ED therapy. Sildenafil was effective in 86.6% of patients. All dimensions of IIEF significantly increased with sildenafil, particularly erectile domain which overall sample mean score improved was 13.2 points (P < 0.001). The greatest increases in satisfaction with all aspects of life were seen in sex life and relationship with partner dimensions. The patients' partners, answered by a minority of partners, were highly satisfied with the treatment and its rapid action, therefore they were in favour of continuing with same. The adverse events occurring were similar to those seen in clinical research on sildenafil in the premarketing phase. No control group was included in this study.

Erectile Dysfunction↗