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Results for “Matched-Pair Analysis”

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At least 19 recordsLinked to original sources

PubMed2024

Histopathologic Features and Transcriptomic Signatures Do Not Solve the Issue of Magnetic Resonance Imaging-Invisible Prostate Cancers: A Matched-Pair Analysis.

BACKGROUND: Multiparametric magnetic resonance imaging (mpMRI) is pivotal in prostate cancer (PCa) diagnosis, but some clinically significant (cs) PCa remain undetected. This study aims to understand the pathological and molecular basis for csPCa visibility at mpMRI. METHODS: We performed a retrospective matched-pair cohort study, including patients undergoing radical prostatectomy (RP) for csPCa (i.e., ISUP grade group ≥ 2) from 2015 to 2020, in our tertiary-referral center. We screened for inclusion in the "mpMRI-invisible" cohort all consecutive men (N = 45) having a negative preoperative mpMRI. The "mpMRI-visible" cohort was matched based on age, PSA, prostate volume, ISUP grade group. Included patients underwent radiological and pathological open-label revisions and characterization of the tumor mRNA expression profile (analyzing 780 gene transcripts, signaling pathways, and cell-type profiling). We compared the clinical-pathological variables and the gene expression profile between matched pairs. The analysis was stratified according to histological characteristics and lesion diameter. RESULTS: We included 34 patients (17 per cohort); mean age at RP and PSA were 70.5 years (standard deviation [SD] = 7.7), 7.1 ng/mL (SD = 3.3), respectively; 65% of men were ISUP 2. Overall, no significant differences in histopathological features, tumor diameter and location, mRNA profile, pathways, and cell-type scores emerged between cohorts. In the stratified analysis, an upregulation of cell adhesion and motility, of extracellular matrix remodeling and of metastatic process pathways was present in specific subgroups of mpMRI-invisible cancers. CONCLUSIONS: No PCa pathological or gene-expression hallmarks explaining mp-MRI invisibility were identified. Aggressive features can be present both in mpMRI-invisible and -visible tumors.

Humans↗

PubMed1977

[Matched-pair analysis--technic and results demonstrated on the example of breast cancer].

The matched pair analysis is a well-known, but rarely used method. This method is recommended for the following problems: preparation of a controlled clinical experiment based upon the results of a retrospective analysis of results of therapy; analysis of results from a controlled clinical experiment in sub-groups; influence of non-therapeutic factors on the prognosis; epidemiological problems and study of the course of diseases. A matched pair analysis of about 300 female patients with breast carcinoma failed to show significant differences between (a) radical mastectomy alone, (b) radical mastectomy followed by chemotherapy with cyclophosphamide, and (c) preoperative irradiation followed by radical mastectomy.

Breast Neoplasms↗

PubMed1976

Untreated endocervical gonorrhea and endometritis following elective abortion.

A matched-pair analysis of 228 cases of endometritis occurring over a two-year period in 4,823 elective abortion patients was carried out. Patients with postabortal endometritis were matched with control subjects for age, parity, race, pay status, time of abortion, and type of abortion procedure. The prevalence of endocervical gonorrhea was 2.7% in the entire group seeking abortion, with 14.7% of patients with gonorrhea subsequently developing endometritis. The matched-pair analysis detected a threefold increased risk for endometritis in patients with untreated gonoccocal endocervicitis when compared with control subjects (p less than 0.05). The significance of these findings to centers performing abortions is discussed.

Abortion, Induced↗

PubMed1977

Induced abortion and subsequent outcome of pregnancy in a series of American women.

We studied the effect of induced abortion on outcome of subsequent pregnancy in a sample of 4896 parturients in Seattle, Washington, from July, 1972, through June, 1976. We used a matched-pair analysis for 571 women with histories of prior abortions. In addition to analyses involving all women with histories of induced abortions, separate analyses were done for 97 black women and 277 primiparas. Histories of prior induced abortions were not related to low birth weight, premature delivery, stillbirth, neonatal death, miscarriage or congenital malformations in subsequent pregnancies. The termination procedure and weeks of gestation at time of termination were not related to the later occurrence of low birth weight or premature delivery.

Abortion, Induced↗

PubMed1977

Heterozygous alpha-1-antitrypsin deficiency and respiratory function in children.

We evaluated 224 children from Rochester, New York, families in which at least one parent was heterozygous for alpha-1-antitrypsin (AAT) deficiency by protease inhibitor (Pi) typing. The childhood population included, of the two major heterozygote Pi types, 75 Pi type MS children and 37 Pi type MZ children. This population was evaluated by means of a standardized respiratory questionnaire, physical examination, and pulmonary function tests. Maximal expiratory flow volume curves were obtained with subjects breathing both air and a helium-oxygen mixture. Total pulmonary resistance by the method of forced oscillations was measured at 3, 5, 7, and 9 cps. No differences in respiratory symptoms or physical findings were seen in Pi type MZ and MS children compared to Pi type MM children. However, when pulmonary function tests were evaluated by a matched-pair analysis designed to minimize other genetic and environmental risk factors, Pi type MZ subjects demonstrated statistically significant differences in forced expiratory flow rates and in increased frequency-dependent characteristics of total pulmonary resistance. These abnormalities are similar to those previously described in adult Pi type MZ subjects, and suggest that physiologic abnormalities associated with AAT deficiency are present early in life.

Adolescent↗

PubMed2001

The power to detect linkage disequilibrium with quantitative traits in selected samples.

Results from power studies for linkage detection have led to many ongoing and planned collections of phenotypically extreme nuclear families. Given the great expense of collecting these families and the imminent availability of a dense diallelic marker map, the families are likely to be used in allelic-association as well as linkage studies. However, optimal selection strategies for linkage may not be equally powerful for association. We examine the power to detect linkage disequilibrium for quantitative traits after phenotypic selection. The results encompass six selection strategies that are in widespread use, including single selection (two designs), affected sib pairs, concordant and discordant pairs, and the extreme-concordant and -discordant design. Selection of sibships on the basis of one extreme proband with high or low trait scores provides as much power as discordant sib pairs but requires the screening and phenotyping of substantially fewer initial families from which to select. Analysis of the role of allele frequencies within each selection design indicates that common trait alleles generally offer the most power, but similarities between the marker- and trait-allele frequencies are much more important than the trait-locus frequency alone. Some of the most widespread selection designs, such as single selection, yield power gains only when both the marker and quantitative trait loci (QTL) are relatively rare in the population. In contrast, discordant pairs and the extreme-proband design provide power for the broadest range of QTL-marker-allele frequency differences. Overall, proband selection from either tail provides the best balance of power, robustness, and simplicity of ascertainment for family-based association analysis.

Alleles↗

PubMedDate not supplied

Environmental risk factors for nasopharyngeal carcinoma: a case-control study in northeastern Thailand.

A case-control study of nasopharyngeal carcinoma was conducted in northeast Thailand, a region which shows an intermediate risk for this neoplasm. The study was conducted to investigate the importance of environmental exposures, particularly salted fish consumption, cigarette smoking, alcohol drinking, and occupational exposure to smoke or dust, as risk factors for the disease. Data from 120 nasopharyngeal cancer cases and the same number of hospital-matched controls indicated that consumption of sea-salted fish at least once a week was a significant risk factor (odds ratio, 2.5; 95% confidence interval, 1.2-5.2). Agricultural workers were also at significantly higher risk (odds ratio, 2.8; 95% confidence interval, 1.3-6.2), and working in agriculture or as a woodcutter was associated with an even higher risk (odds ratio, 8.0; 95% confidence interval, 2.3-28.2). There was no association between nasopharyngeal carcinoma and alcohol drinking or cigarette smoking.

Adolescent↗

PubMedDate not supplied

Thyroid hormones and duration of ovulatory activity in the etiology of breast cancer.

We conducted the present study with the hypothesis that conflicting reports on the association between mild hypothyroidism and breast cancer may be due to failure to consider the potential interaction between thyroid and ovarian hormones. Seventy-three cases of breast cancer and 75 hospital controls were studied. The overall matched multivariate odds ratio of breast cancer for the lowest tertile of free T4 (< or = 1.10 ng/dl) versus the two other tertiles was 1.7 (95% confidence limits, 0.6-5.0). However, there was a statistically significant linear trend (P = 0.04) in the odds ratios for breast cancer related to subnormal free T4 levels across tertiles of duration of ovulatory activity. These results suggest that women combining low levels of circulating free T4 with long duration of ovulatory activity may be at increased risk for this disease.

Adult↗

PubMedDate not supplied

Folate, vitamin C, and cervical intraepithelial neoplasia.

A case-control study was designed to assess the relationship between cervical intraepithelial neoplasia (CIN) and folate in serum, red blood cells, and diet. The association between CIN and dietary vitamin C was also investigated. Cases were selected from women with biopsy-confirmed CIN. Controls were age-, race-, and clinic-matched women with normal cervical (Pap) smears. Study participants completed self-administered food frequency (n = 100 matched pairs) and health (n = 102 matched pairs) questionnaires. Fasting venous blood samples were collected for serum (n = 98 matched pairs) and red cell (n = 68 matched pairs) folate assays. Conditional logistic regression models were used to estimate crude odds ratios and odds ratios adjusted for smoking, income, number of sexual partners, frequency of cervical smear, use of spermicidal contraceptive agents, history of genital warts, and Quetelet index. Dietary intake variables were adjusted for total energy intake prior to logistic regression. A protective effect of red cell folate was evident with adjusted odds ratios (95% confidence intervals) of 0.1 (0.0-0.4), 0.6 (0.2-2.0), and 0.5 (0.2-1.9) for those in quartiles 4 (highest), 3, and 2 compared to quartile 1 (lowest). Supporting evidence for the protective effect of folate was provided by inverse associations between CIN and folate in both serum and diet. An inverse association was also found between CIN and dietary vitamin C with adjusted odds ratios (95% confidence intervals) of 0.2 (0.0-0.7), 0.6 (0.2-1.6), and 0.6 (0.2-1.8) for those in quartiles 4, 3, and 2, respectively, compared to quartile 1. These findings support dietary recommendations, such as those of the American Cancer Society, the National Cancer Institute, and the U.S. Dietary Guidelines, which allow for adequate intake of folate and vitamin C, both of which are found in good quantity in fruits and vegetables. Increased consumption of legumes and whole grains is also in accord with current dietary recommendations, and both of these types of foods are good sources of folates.

Adolescent↗

PubMed1992

[Percutaneous mitral valvulotomy: comparison of 2 techniques in 100 matched-pair patients].

The results of percutaneous mitral valvulotomy by the Double Balloon and the Inoue Balloon were compared in 100 patients referred to Marie-Lannelongue Hospital between 7/11/86 and 8/3/91, paired for age, sex and echocardiographic features of the mitral valve. The transvalvular diastolic pressure gradient at catheterisation or Doppler echocardiography decreased significantly and similarly with the two techniques: -65 +/- 19% versus -64 +/- 15% (p = 0.10) and -66 +/- 22% versus -58 +/- 23% (p = 0.20) for the Double-Balloon and the Inoue Balloon techniques respectively. Similarly, the mitral valve surface area measured by planimetry during echocardiography or calculated from the Gorlin formula increased by 0.9 +/- 0.39 cm2 with the Double Balloon and by 0.88 +/- 0.32 cm2 with the Inoué Balloon (p = 0.91) or by 0.98 +/- 0.62 cm2 versus 0.87 +/- 0.45 cm2 (p = 0.42). The number of commissures opened was the same with both techniques. The evolution of mitral regurgitation after dilatation was similar: stable or less severe in 61% dilated by the Double Balloon and 68% by the Inoue Balloon; aggravation by more than one grade in 7 and 5% respectively (p = 0.17). Complications were rare and comparable with both techniques. The results with the two methods were the same if patients with an optimal indication and those with more severe mitral valve disease were considered separately. The rapidity and simplicity of percutaneous mitral valvulotomy with the Inoué Balloon make it the technique of choice.

Adolescent↗

PubMedDate not supplied

Study of intrarenal vasculature in cases of primary and secondary hypertension (by metallic impregnation technique on whole kidney section)

Study of intrarenal vasculature was carried out by using the metallic impregnation technique on whole kidney sections in 31 [corrected] cases of (primary and secondary) hypertension and 10 normal controls. Distinct patterns of intrarenal vasculature were noted in controls and in cases of hypertension. Gradual tapering of vessels, absence of tortuosity and good peripheral vascularisation were noted in controls. Abrupt tapering, tortuosity of vessels and poor peripheral vascularisation were noted in hypertensive cases. In essential hypertension moderate to severe changes of dilatation of the segmental and/or arcuate arteries was noted. The degree of dilatation was related to the level of systolic BP rather than diastolic in cases of essential hypertension. Secondary hypertension even if severe, rarely showed significant dilatation lesions. Avascular zones and conglomeration of vessels at poles was seen only in cases of pyelonephritis. This helped in distinguishing these, from cases of glomerulonephritis.

Adolescent↗

PubMed1992

Coronary artery bypass graft surgery in older women and men.

OBJECTIVE: To compare women and men younger than 70 years of age and 70 years or older undergoing coronary artery bypass surgery. DESIGN: Retrospective chart review, case-control series. SETTING: University medical center. PATIENTS: All women (n = 465) having first-time isolated coronary artery bypass surgery between 1983 and 1988, and 465 men matched for age and year of surgery. Predominantly white; 33% were 70 years or older. MEASURES: Medical record data: demographics, preoperative comorbidities, perioperative and postoperative complications, mortality, length of stay. RESULTS: Preoperatively, women 70 years of age or older had a higher incidence of congestive heart failure, renal disease and hypertension, and a lower incidence of smoking history compared with women less than 70 years old. Men 70 years or older had a higher incidence of congestive heart failure and renal disease, and a lower incidence of smoking history compared with men less than 70 years old. There was no difference in mortality between older and younger women, whereas the mortality rate for older men was higher than that for younger men. There were fewer differences between women younger than 70 and those 70 years or older in incidence of postoperative complications than between men of those same age groups. Among patients 70 years or older, incidence of postoperative congestive heart failure was greater in women than in men. There were no other differences between women and men younger than 70 and those 70 years or older in incidence of postoperative complications. Controlling for the influence of postoperative complications, age was related to length of stay for women and men. CONCLUSIONS: Older women were at no greater risk of mortality or the occurrence of postoperative complications compared with younger women or older men. A functional component influencing recovery and length of hospital stay needs to be considered to provide optimal nursing care after surgery.

Adult↗

PubMed1975

Matched-pairs study of reserpine use and breast cancer.

This paper reports on an analysis of psychiatric population. 55 female patients with breast cancer were matched with non-cancer patients on age, year of admission, psychiatric diagnosis, race, and religion. Reserpine use was examined for yearly use by each year preceding the diagnosis of breast cancer, by cumulative yearly use, and by other defined time periods. Regardless of the definition of reserpine user, there were no significant increased relative risks of breast cancer for those women on reserpine. There was a fairly low proportion of patients from each group who were on the drug in any given year, and a fairly wide range of total dosage received. Over half of the women used reserpine at some time during their hospital stay.

Aged↗

PubMed1975

Histological evaluation of gingival damage by toothbrushing. An experimental study in dog.

The purpose of the investigation was to present an experimental model for a comparative histological evaluation of the effect on gingiva using two different types of bristle material at tooth brushing. Fifteen dogs constituted the material. Two different teeth or groups of teeth were selected on each dog. One tooths was brushed with a nylon brush. The diameter of the bristles was approximately 0.25 mm. The other tooth was brushed with a polytene brush. The diameter of the bristles vary between 0.7 mm at the base of the bristle to 0.25 mm in the near end of the bristle. Manual brushing during 10-60 seconds was carried out in 7 dogs and the other eight dogs were brushed with a mechanical device for 10-30 seconds. A histological evaluation of the relative degree of tissue damages based upon a grading of these damages in terms of a 0-3 point scale was carried out by two independent observers. Wilcoxon's matched-pair signed rank test was applied for a statistical analysis of the result of the histological examination. The conclusion was that the two different types of brushes most likely cause different damages on the gingival tissue and that the polytene brush appeared to cause less tissue damage than the nylon brush.

Animals↗

PubMed1979

Bottle feeding as a risk factor for cholera in infants.

To determine risk factors for cholera in infants, a retrospective matched-pair study of 42 cases and their controls was undertaken during an outbreak of El Tor cholera in Bahrain in the autumn of 1978. The highest attack-rate of cholera (125/10 000) occurred in infants in the 6--11 month age-group, which corresponds to the weaning age in this community. Significantly more cases than controls were principally bottle fed (greater than 50% milk intake by bottle) than principally breast fed during the week before onset of illness (p=0.004). Analysis of various patterns of breast and bottle feeding did not determine whether the protection afforded by breast feeding was a negative effect (due to the lack of exposure to contaminated bottle feedings for breast fed infants) or a positive effect (due to protective functions of constituents of human breast milk). Cholera infection (with or without symptoms) among mothers of either case or control infants was uncommon (case mothers 3, control mothers 5), and mean serum vibriocidal and antitoxic antibody levels were similar for the two groups of mothers. These observations suggest that maternal infection did not affect the relative risk of infants having symptomatic cholera.

Antibodies, Bacterial↗

PubMed1975

Induced abortion and subsequent outcome of pregnancy. A matched cohort study.

The effect on subsequent pregnancy outcome related to abortion was studied in a sample of 26,000 births in Taiwan. When no adjustment was made for confounding maternal variables, significant relationships were found between previous abortion and various problems of outcome of subsequent pregnancies. However, in a matched-pair cohort study controlling for relevant maternal characteristics, all such relationships disappeared. It is concluded that the deleterious effects of abortion on subsequent pregnancy outcome reported by others may be a consequence of the failure to adjust for maternal factors which are related both to abortion status and pregnancy outcome, and not to abortion itself.

Abortion, Induced↗

PubMed1992

Effects of delta sleep-inducing peptide on sleep of chronic insomniac patients. A double-blind study.

The influence of delta sleep-inducing peptide (DSIP) on sleep was studied in 16 chronic insomniac patients according to a double-blind matched-pairs parallel-groups design. Subjects slept for 5 consecutive nights in the laboratory. Night 1 was used for adaptation, night 2 for baseline measurements. In the afternoon before the 3rd, 4th and 5th night, half of the patients received intravenously 25 nmol/kg body weight DSIP, and half of the patients a glucose solution (placebo). Measures for sleep structure, objective (polysomnography) and subjective sleep quality and for subjective tiredness were assessed. The results for objective sleep quality indicated higher sleep efficiency and shorter sleep latency with DSIP as compared to placebo. One measure of subjectively estimated tiredness decreased within the DSIP group. Data analysis suggested, however, that the statistically significant effects were weak and in part could be due to an incidental change in the placebo group. As none of the other measures, including subjective sleep quality, showed any change, it was concluded that short-term treatment of chronic insomnia with DSIP is not likely to be of major therapeutic benefit.

Adult↗

PubMedDate not supplied

Health of workers exposed to 1, 1, 1,-trichloroethane: a matched-pair study.

An epidemiologic study of 151 matched pairs of employees was conducted in two adjacent textile plants, one of which used inhibited 1,1,1-trichloroethane as a general cleaning solvent. Employees in the study population had exposures to the solvent for 6 yrs or less at varying concentrations which were measured by breathing zone sampling and personal monitoring. While cardiovascular and hepatic observations were of primary interest, other health parameters were also studied. Application of sensitive statistical techniques and careful examination of all data did not reveal any clinically pertinent findings that were associated with exposure to 1,1,1-trichloroethane. The statistically significant associations that were observed between health measures and nonexposure factors emphasize the need to consider age, sex, race, and other variables in designing epidemiologic studies.

Adolescent↗