Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Matched Groups”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources
PubMed1997

Deprenyl, excess mortality, and epidemiological traps.

Compared with the findings for an age-matched group not taking deprenyl, a higher risk of mortality in Parkinson's disease patients taking deprenyl has recently been reported. Since a biological basis for this observation was not apparent, an epidemiological explanation was sought. Expected mortality over a 6-year period in four hypothetical age-matched groups was determined. Although groups were age matched, ages of individuals within the groups varied. Variation of individual ages within each group, without affecting the age-match comparability, produced a marked variation in expected group mortality. Mortality comparisons between age-matched groups can be invalid. This epidemiological trap might account for the recent unexplained high mortality observed in a group of Parkinson's disease patients taking deprenyl.

Age Factors↗
PubMed2005

The salivary microbiota as a diagnostic indicator of oral cancer: a descriptive, non-randomized study of cancer-free and oral squamous cell carcinoma subjects.

BACKGROUND: The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. METHODS: Unstimulated saliva samples were collected from 229 OSCC-free and 45 OSCC subjects and evaluated for their content of 40 common oral bacteria using checkerboard DNA-DNA hybridization. DNA counts per ml saliva were determined for each species, averaged across subjects in the 2 subject groups, and significance of differences between groups determined using the Mann-Whitney test and adjusted for multiple comparisons. Diagnostic sensitivity and specificity in detection of OSCC by levels of salivary organisms were computed and comparisons made separately between a non-matched group of 45 OSCC subjects and 229 controls and a group of 45 OSCC subjects and 45 controls matched by age, gender and smoking history. RESULTS: Counts of 3 of the 40 species tested, Capnocytophaga gingivalis, Prevotella melaninogenica and Streptococcus mitis, were elevated in the saliva of individuals with OSCC (p < 0.001). When tested as diagnostic markers the 3 species were found to predict 80% of cancer cases (sensitivity) while excluding 83% of controls (specificity) in the non-matched group. Diagnostic sensitivity and specificity in the matched group were 80% and 82% respectively. CONCLUSION: High salivary counts of C. gingivalis, P. melaninogenica and S. mitis may be diagnostic indicators of OSCC.

Adolescent↗
PubMed2004

Total knee arthroplasty in obese patients: a comparison with a matched control group.

Thirty knees in 27 obese patients were matched to 30 knees in 27 nonobese patients, with both cohorts followed for a mean of approximately 15 years. Nine of 30 obese knees were revised, whereas 3 of 30 nonobese knees were revised, with Knee Society objective scores being higher in the nonobese group. There were more polyethylene insert revisions in the nonobese group, which may have been accounted for by a trend of higher activity levels in this group. The authors concluded that at long-term follow-up, although not statistically significant, there was a trend for obesity to influence the rate of aseptic loosening. This may occur because of increasing stress at the bone-prosthesis interface, whereas increased activity levels in the nonobese patients may adversely affect the longevity of the polyethylene insert.

Adult↗
PubMed1997

Project MATCH secondary a priori hypotheses. Project MATCH Research Group.

AIMS: (1) To assess the benefits of matching alcohol dependent clients to three treatments, based upon a priori hypotheses involving 11 client attributes; (2) to discuss the implications of these findings and of matching hypotheses previously reported from Project MATCH. SETTING AND PARTICIPANTS: (1) Clients receiving outpatient therapy (N = 952; 72% male); (2) clients receiving aftercare therapy following inpatient or day hospital treatment (N = 774; 80% male). INTERVENTION: Clients were randomly assigned to one of three 12-week, manual-guided, individual treatments: Cognitive Behavioral Coping Skills Therapy (CBT), Motivational Enhancement Therapy (MET) or Twelve-Step Facilitation Therapy (TSF). DESIGN: Two parallel but independent randomized clinical trials were conducted, one with outpatients, one with aftercare clients. Participants were monitored over 15 months including a 1-year post-treatment period. Individual differences in response to treatment were modeled as a latent growth process and evaluated for 17 contrasts specified a priori. Outcome measures were percentage of days abstinent and drinks per drinking day. FINDINGS: Two a priori contrasts demonstrated significant post-treatment attribute by treatment interactions: (1) outpatients high in anger and treated in MET had better post-treatment drinking than in CBT; (2) aftercare clients high in alcohol dependence had better post-treatment outcomes in TSF; low dependence clients did better in CBT. Other matching effects varied over time, while still other interactions were opposite that predicted. CONCLUSIONS: (1) Anger and dependence should be considered when assigning clients to these three treatments; (2) considered together with the results of the primary hypotheses, matching effects contrasting these psychotherapies are not robust. Possible explanations include: (a) among the client variables and treatments tested, matching may not be an important factor in determining client outcomes; (b) design issues limited the robustness of effects; and (c) a more fully specified theory of matching is necessary to account for the complexity of the results.

Adult↗
PubMedDate not supplied

Automated mapping of observation codes using extensional definitions.

OBJECTIVE: To create "extensional definitions" of laboratory codes from derived characteristics of coded values in a clinical database and then use these definitions in the automated mapping of codes between disparate facilities. DESIGN: Repository data for two laboratory facilities in the Intermountain Health Care system were analyzed to create extensional definitions for the local codes of each facility. These definitions were then matched using automated matching software to create mappings between the shared local codes. The results were compared with the mappings of the vocabulary developers. MEASUREMENTS: The number of correct matches and the size of the match group were recorded. A match was considered correct if the corresponding codes from each facility were included in the group. The group size was defined as the total number of codes in the match group (e.g., a one-to-one mapping is a group size of two). RESULTS: Of the matches generated by the automated matching software, 81 percent were correct. The average group size was 2.4. There were a total of 328 possible matches in the data set, and 75 percent of these were correctly identified. CONCLUSIONS: Extensional definitions for local codes created from repository data can be utilized to automatically map codes from disparate systems. This approach, if generalized to other systems, can reduce the effort required to map one system to another while increasing mapping consistency.

Algorithms↗
PubMed2006

Functional treatment and early weightbearing after an ankle fracture: a prospective study.

OBJECTIVE: Postoperative care for ankle fractures is generally 1 of 2 regimens: 1) functional treatment combined with early weightbearing (EWB), or 2) immobilization in a cast/orthosis for 6 weeks without weightbearing (6WC). The objective of this study was 2-fold: 1) to follow a prospective group treated with EWB as to long-term subjective and objective outcomes, and 2) to compare a subset of this group with a matched group of historic controls treated with 6WC. DESIGN: Prospective, clinical, cohort observation, and retrospective matched pair analysis. SETTING: University hospital, level 1 trauma center. PATIENTS: Forty-three patients (20 males; mean age, 49 +/- 14 years) with operated Weber B/C fractures underwent EWB. For comparison, 23 patients of this group were matched to a same number of historic controls with respect to age, gender, body mass index, and fracture type. INTERVENTION: Open reduction and internal fixation (ORIF) using a 1/3-tubular-fibula-plate for the fibula, and malleolar screws for the medial malleolus fracture (in cases with a bimalleolar ankle fracture) followed by EWB or 6WC. MAIN OUTCOME MEASUREMENTS: Olerud and Tegner scores at follow-up (at least 12 months after surgery), time to full weightbearing, return to work, pain intensity (numerical rating scale (NRS)), and hospital stay. Statistical comparisons were performed by using the Mann-Whitney U test or Fisher exact test (P < 0.05). RESULTS: Patients with EWB were full weightbearing at 7 +/- 3 weeks and returned to work at 8 +/- 5 weeks after surgery. At follow-up (mean, 20 +/- 11 months after surgery), all EWB patients showed good results in the Olerud score (90 +/- 13 points). Matched-pair analysis in 23 patients in each group revealed differences between EWB and 6WC groups for hospital stay (mean, 10.8 +/- 4.7 vs. 13.6 +/- 6 days; P = 0.12), time to full weightbearing (mean, 7.7 +/- 3.1 vs. 13.5 +/- 9.4 weeks; P = 0.01), and time until return to work (mean 9.2 +/- 5.5 vs. 10.8 +/- 7 weeks; P = 0.63). No differences concerning pain intensities were observed (EWB vs. 6WC: NRS = 1.9 vs. 1.7; P = 0.12). At follow-up, Olerud scores were generally considered good for both groups; however, mean values in EWB patients were slightly higher (87 +/- 14 vs. 79 +/- 19 points; P = 0.25). In both groups, the majority of patients reached their preinjury level of activity as demonstrated by Tegner scores. CONCLUSIONS: EWB patients tolerated earlier full weightbearing compared with 6WC patients, and there were no disadvantages with EWB compared with 6WC concerning hospital stay, pain intensities, time until return to work, and Olerud/Tegner Scores. Potential candidates for EWB are patients with a stable osteosynthesis of their fractured ankles as judged by the responsible surgeon, compliance, and high motivation.

Activities of Daily Living↗
PubMed2003

The outcome of in vitro fertilization in advanced endometriosis with previous surgery: a case-controlled study.

OBJECTIVE: This study was undertaken to evaluate the outcome of in vitro fertilization (IVF) in patients with advanced pelvic endometriosis and previous surgical treatment. STUDY DESIGN: A case controlled study was performed. RESULTS: Patients with the diagnosis of stage IV endometriosis with previous surgical treatment were treated by IVF (group A = 85). An age-matched group of patients (group B = 177) with tubal factor infertility were treated with the same protocol of IVF. In group A, cycle cancellation because of poor response occurred in 29.7% compared with 1.1% in the control group (relative risk 26.03, 95% CI 6.02-112.45). There were 13 (15.3%) clinical pregnancies per stimulated cycle in group A compared with 93 (52.5%) clinical pregnancies in the control group, P <.0001 (odds ratio 0.29, 95% CI 0.15-0.55). CONCLUSION: The outcome of IVF in stage IV endometriosis with previous surgery was significantly lower compared with an age-matched group of tubal factor infertility.

Adult↗
PubMed1990

Morphometric analysis of vertebrae and intervertebral discs as a basis of disc replacement.

In this study measurements were obtained from 359 vertebrae and 215 intervertebral discs in an attempt to classify discs by their size. At the cervical and thoracic levels, this attempt was unproductive because of extensive variations. In the lumbar spine, discs were allocated to six size-matched groups and to two height-matched groups. The breadth of marginal rims were also measured with a view to provide surgeons operating on the spine with precise data on disc morphology to facilitate disc replacement.

Adolescent↗
PubMed1995

Sequential memory in children with and without language impairment.

Serial recall was studied in children with language impairment and two groups of normally achieving controls: a group matched for age and a younger group matched for reading and memory capacity. Participants were presented lists of digits that were one item longer than their memory span, in conditions requiring either written or oral recall. Digit lists were presented either with or without a final nonword item, or "suffix," that was capable of interfering with memory for items at the end of the list. The main finding was that the list-final suffix effect was substantially larger than normal in children with language impairment, even though other aspects of their recall were normal. This deficiency in children with language impairment was evident only under a scoring system that credited recall of items in their correct serial positions, not under scoring systems that credited memory for the presence of items or their sequence. Results are interpreted according to the hypothesis that children with language impairment are more dependent upon relatively unanalyzed acoustic and phonetic representations of speech than are other children.

Child↗
PubMed1994

Melancholia: a Defense Mechanism Test study.

The defensive organization of Melancholia was explored with a tachistoscopic percept-genetic technique, the Defense Mechanism Test. A sample of 20 women inpatients with a DSM-III-R diagnosis of Major Depressive Episode or Major Depression, Melancholic Type was contrasted with a matched group of depressed outpatients and a matched group of nonclinical subjects. Signs of introaggression on the hero, statue-repression, and stereotypy significantly characterized melancholic patients. The latter were discriminated from depressed outpatients as showing more signs of stereotypy and of discontinuity. Mask-disguise defenses were typically endorsed by Bipolar melancholic patients and significantly differentiated them from Unipolar melancholic patients. One type of stereotypy (regarding wrong age attributes of the central figure) successfully predicted a poor response to antidepressive therapy. Relevant modifications of the current Defense Mechanism Test coding criteria for stereotypy are proposed.

Adult↗
PubMed1997

Decreased blood level of beta 2-microglobulin in the employees of a factory which produced polychlorinated biphenyls.

Under the project of evaluating the health status of the employees of CHEMKO factory (East Slovakia) which produced PCBs between 1955 and 1985, the level of beta 2-microglobulin (beta 2-m) was measured in the serum of 242 subjects from CHEMKO (Group A) and two control groups from much less polluted areas: 1,277 females from a small mountainous village (Group B), 2,179 adults from the area of a large city of Kosice (Group C). The level of thymidine kinase (TK) was measured in the groups A and B only. In addition, age-matched groups of 155 women each from all areas were evaluated. In both the whole group and the age-matched group from CHEMKO the level of beta 2-m was significantly lower (P < 0.001) than that in the respective control groups, while no difference was found in the level of TK. In conclusion, it is suggested that the decrease of beta 2-m in CHEMKO employees might be related to the immunotoxic effects of organochlorines.

Adult↗
PubMed2004

Cementless metal-on-metal hip arthroplasty in patients less than 50 years of age: comparison with a matched control group using ceramic-on-polyethylene after a minimum 5-year follow-up.

Thirty-nine cementless hip arthroplasties using metal-on-metal articulation were consecutively implanted in 30 patients less than 50 years of age and compared with a matched control group (by age, diagnosis, Devane activity, and Harris hip scores) of cementless arthroplasties using ceramic-on-polyethylene articulation. The Harris hip score at follow-up (minimum 5 years) for the metal-on-metal was 94.9 (range, 74-100). After the same follow-up, the results of the ceramic-on-polyethylene were significantly worse: 9 osteolyses and 7 surgical revisions related to wear (none in the metal-on-metal). Five-year survival rates were 97% +/-2% for the ceramic-on-polyethylene and 100% for the metal-on-metal. The metal-on-metal may be recommended to prevent wear problems in younger and more active patients; however, a longer follow-up is required to confirm this encouraging data.

Adult↗
PubMed1993

The performance of children with language-learning disabilities on two types of cognitive tasks.

The performance of children with language-learning disabilities on two types of cognitive tasks was compared to that of two groups without language-learning disabilities, one matched for mental age and the other for language (vocabulary) age. The first task, Concept Formation, measured one's ability to identify and state the rule for a concept about a set of colored geometric figures when shown instances and noninstances of the concept. The second task, Analysis Synthesis, required the identification and use of a solution key to solve an incomplete logic puzzle. Both tasks involved increases in complexity as additional items were administered. Results indicate that the children with language-learning disabilities performed at a level commensurate with the language-matched group on the Concept Formation task, and at a level commensurate with the mental-age matched group on the Analysis-Synthesis task. The implications of these findings for the nature of language-learning disabilities are discussed.

Adolescent↗
PubMedDate not supplied

Computed tomography of the brain in cases with venous vasculitis compared with an age-matched reference group.

Patients with a particular, steroid-sensitive headache and often characteristic pathology at orbital phlebography, have been suggested to suffer from venous vasculitis. Fifty such patients were examined with computed tomography (CT) of the brain. The findings were compared with those of an age-matched reference group selected at random to represent normal subjects. The CT examinations were analyzed with respect to size of lateral ventricles and signs of atrophy. In both groups, there was a significant increase of atrophy with age. There was also a significantly higher degree of atrophy in the patient group as compared with the reference group. The findings indicate that the supposedly underlying venous vasculitis is related to early aging and atrophy of the brain.

Adult↗
PubMed1991

Postoperative infusional continuous regional analgesia. A technique for relief of postoperative pain following major extremity surgery.

A new technique using postoperative infusional continuous regional analgesia (PICRA) for postoperative pain relief was investigated in 23 surgical patients treated by amputation (12 patients) or by limb-salvage resection operations (11 patients). Bupivacaine was delivered into peripheral nerve sheaths via catheters placed therein at the time of surgery. Only patients in whom the nerves were easily accessible were treated. Catheters were placed in the axillary sheath, the lumbosacral trunk, and the femoral nerve sheaths of patients treated with shoulder girdle and pelvic procedures (resections and amputations), and within the sciatic nerve sheath of those treated with lower extremity procedures. The anesthetic agent was delivered at controllable rates. Regional analgesia was obtained in the operative site with minimal motor or sensory decrease. To assess the efficacy of this technique, the results of this study group were compared with those of a matched group of 11 patients treated with similar surgical procedures but who received epidural morphine. Eleven of the 23 patients on PICRA required no supplemental narcotic agents. The mean level of the narcotic agents required by the remaining 13 PICRA patients was approximately one third of that required by the matched group of 11 patients receiving epidural morphine. Overall, the patients on PICRA had an 80% reduction of narcotic requirements when compared to the historical controls. The technique is reliable and can be performed by the surgeon, requiring about a ten-minute increase in operating time. It has potentially wide application in orthopedics in procedures in which the major nerves are easily accessible (e.g., pelvic fractures and revision hip surgery) and for patients with intractable pain of the extremities.

Amputation, Surgical↗
PubMed1994

Retrospective description and experimental reconstitution of three different responses of the baboon to lethal E. coli.

This paper is divided into a retrospective descriptive section in which we report on three distinctly different and spontaneous responses of the baboon to LD100 Eschericia coli observed over the last 6 years. This section is followed by an experimental section in which we reproduce the immediate and delayed responses based on hypothetical mechanisms. In the descriptive section, we arbitrarily divided all the non-survivor animals on which we had sufficient data into three groups based on duration of survival (i.e., 12 hr or less, immediate, 12 to 30 hr, intermediate, and 30 hr or more, delayed). The natural history and pathophysiology of the 12 hr or less group matched that of capillary leak syndrome with a rapid fall in blood pressure, rise in hematocrit, massive edema, and congestion with leukocyte sequestration in both lung and liver, with only limited adrenal cortical hemorrhage. The 12 to 30 hr group matched the natural history of a consumptive hemorrhagic diatheses with a biophasic blood pressure response, limited change in hematocrit, a severe consumptive coagulopathy, severe adrenal cortical hemorrhage, and a moderate renal cortical tubular necrosis, but limited renal cortical thrombosis. The greater than 30 hr group matched the natural history of a microvascular thrombotic (hemolytic uremic) syndrome with a stable blood pressure, a fall in hematocrit associated with a massive renal cortical thrombosis with a severe medullary, and cortical tubular necrosis. We did not analyze these groups further (i.e., type of intervention etc.) once we found that time of survival correlated with a unique clinical syndrome, because based on these observations, we hypothesized that we could reproduce the immediate capillary leak and pulmonary failure, and the delayed microvascular thrombosis and renal failure syndromes experimentally. We reproduced the immediate (< 12 hr) and delayed (> 30 hr) responses by infusion of either tumor necrosis factor or C4b binding protein with sublethal E. coli. This provides models of the immediate and delayed as well as the intermediate responses to E. coli for study of mechanism and the efficacy of therapeutic interventions.

Animals↗
PubMed2005

Clinical evaluation of circulating interleukin-6 and interleukin-10 levels after surgery-induced inflammation.

BACKGROUND: It was previously reported that both pro- and anti-inflammatory cytokines are elevated in systemic inflammatory response syndrome (SIRS). Cytokine-mediated systemic neutrophil activation is a direct consequence of SIRS, and can lead to multiple organ dysfunction syndrome (MODS). This prospective study assessed the risk of SIRS and MODS after orthognathic surgery by measuring the circulating levels of inflammatory cytokines such as IL-6 and IL-10 as well as the neutrophil functions as a marker of organ failure. MATERIALS AND METHODS: Blood samples for the measurement of IL-6, IL-10, CRP, neutrophil counts, and neutrophil function were drawn from 21 patients with mandibular prognathism at 2 days before, and at 1 and 3 days after orthognathic surgery. The neutrophil function was estimated by superoxide production and elastase release under the stimulation of FMLP. RESULTS: Eight of the 21 patients were applicable to SIRS criteria 1 day postoperatively, and all of the subjects were excluded from SIRS criteria 3 days postoperatively. Although IL-6 and IL-10 levels were raised 1 day postoperatively, increased cytokine concentrations were decreased in most patients at 3 days postoperatively. The IL-6 concentration and the ratio of IL-6 to IL-10 were higher in the SIRS-matched group compared with the non-SIRS-matched group. Neutrophil priming for superoxide production and elastase release was discovered 1 day after orthognathic surgery, and differences in those values could not be distinguished between the groups. CONCLUSIONS: These results suggest that a few patients in whom high levels of circulating inflammatory cytokine and neutrophil-derived toxic factor continue may have a possibility of contracting severe diseases such as SIRS and MODS after orthognathic surgery. We conclude that the ratio of IL-6 to IL-10 may be a predictive factor in SIRS.

Adult↗
PubMed1992

The translocation t(1;22)(p13;q13) is a nonrandom marker specifically associated with acute megakaryocytic leukemia in young children.

We present the nonrandom occurrence, frequency, and degree of immunophenotype association of the t(1;22)(p13;q13) in children with acute nonlymphocytic leukemia (ANLL). This karyotype anomaly occurred in leukemia cells from five of 445 (1.1%) children with newly diagnosed ANLL who were successfully studied by cytogenetic analysis at four European centers between January 1987 and January 1992. The occurrence of the t(1;22) was restricted to the French-American-British classification (FAB) subtype M7. The overall incidence in children with acute megakaryocytic leukemia (AMKL) was 27.8% (5/18 cases); in infants with AMKL, the frequency of the t(1;22) was 66.7% (4/6 cases). Three of the patients carrying this anomaly had a diploid karyotype, whereas in two cases a hyperdiploid karyotype was found. However, in all five patients, the t(1;22) was the only translocation event present at diagnosis. All patients received aggressive chemotherapy for acute myelogenous leukemia (AML). Two patients died within 15 months of diagnosis without entering remission. One of three patients who entered remission died 7 months after diagnosis, most likely from intramedullar hemorrhage. Only two of the five children with the t(1;22) who received autologous bone marrow transplantation (BMT) are alive and in complete remission (CR) 23 and 40 months after diagnosis, respectively. At the time of diagnosis, the age of the oldest child carrying the t(1;22) was 18 months. The cases with this chromosome anomaly were compared with an age-matched group of five children with AMKL lacking this translocation. The patients with the t(1;22) had a lower median value of the peripheral white blood cell (WBC) count and a higher median hemoglobin level than the patients from the matched group. In the latter cases, normocellular or hypercellular bone marrow (BM) was detected at diagnosis. In contrast, all children with the t(1;22) in our series had a hypocellular BM. Histological BM analyses were available in three of these patients and showed marked fibrosis. Other clinical and laboratory parameters showed no obvious differences between the matched groups. Despite intensive chemotherapy, AMKL in children appears to be associated with a poor prognosis. The clinical courses of the children with AMKL and the t(1;22) presented may be indicative of a beneficial effect of autologous BMT in this subset of patients.

Antineoplastic Combined Chemotherapy Protocols↗