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PubMed1994

[Exophthalmometry and thyroid disease. The value of the Hertel measurement evaluated by a group of patients with thyroid diseases and a control group].

Exophthalmometry values from routine referrals to a hospital eye clinic are analysed, including adult patients with and without thyroid disease. In thyroid disease without eye motility complaints (n = 90) the median exophthalmometry value was 18 mm (range 12-28 mm). Thyroid patients with eye muscle involvement (diplopia, n = 47) had significantly higher values (median 22 mm, range 15-31 mm) but did not differ significantly from a subgroup of 51 patients without thyroid disease, but with "big eyes" as a (presumably) physiological finding (median value 20 mm, range 16-25 mm). The above three categories were all excluded from the control group (n = 203) which had 16 mm as median value, range 11-23 mm. Mean values were 16.0 +/- 1.8 mm in the females and 16.5 +/- 2.3 mm in the male controls. A side difference in exophthalmometry value > or = 2 mm appeared in 34% of thyroid patients with eye muscle involvement. This appeared in only a few per cent in the three other groups. Due to the wide overlap between groups, the solitary exophthalmometry reading is of limited diagnostic value, while the importance of exophthalmometry is evident when following the individual patient with orbital disease.

Adolescent↗
PubMed1998

Sex hormones and lipoproteins in adolescent male offspring of parents with premature coronary heart disease and a control group.

OBJECTIVE: To compare pubertal maturation, sex steroid hormones, and lipoproteins and their interrelationships in male offspring of parents with premature coronary heart disease (cases) and a control group. DESIGN: This was a cross-sectional comparison of cases and members of a control group 10 to 15 years of age. SUBJECTS AND METHODS: Offspring were recruited from patient lists of area physicians. Members of the control group were recruited from area schools. Body mass (kg/m2), serum lipids, lipoproteins, apolipoproteins, estradiol, and free testosterone were measured. RESULTS: Differences in age were not significant, but offspring were taller, heavier, and more mature. Offspring had higher total and low density lipoprotein cholesterol. Offspring had lower estradiol levels in early puberty but higher levels in late puberty. With family history and body mass in the regression models for lipid parameters, free testosterone was a significant explanatory factor for total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein, and estradiol was a significant predictor for apolipoprotein B. The percent of the variance in the lipid parameters explained by testosterone and estradiol was small. CONCLUSION: Sex hormone concentrations appear to be modest but significant predictors of lipoprotein and apolipoprotein concentrations in offspring and a control group in cross-sectional analysis. After controlling for pubertal maturation, hormone and lipid concentrations differed in offspring and the control group.

Adolescent↗
PubMed1981

Weaning trait comparisons among inbred lines and selected noninbred and randomly bred control groups of Rambouillet, Targhee and Columbia sheep.

A program of inbreeding with concurrent selection was followed in the development of 26 Rambouiller, 20 Targhee and 10 Columbia inbred lines for subsequent linecross and topcross performance evaluation. Inbreeding coefficients averaged 30.4, 28.5 and 29.8% for the three breeds, respectively, at the end of the study. Selected noninbred control and unselected randomly bred control groups were maintained for each breed. Weaning trait data were evaluated for 1,332 Rambouillet, 1,557 Targhee and 1,049 Columbia inbred line and control group lambs during the final 2 years of inbreeding. Results showed a slight response to selection within inbred lines for the more highly heritable traits and some degree of genetic divergence among lines at the current levels of inbreeding. In general, the traits most sensitive to inbreeding depression were those more closely associated with fitness and those of low to moderate heritability. Even though a fairly large number of lines was developed, only a few inbred lines were superior (P less than .05) to their respective selected control groups - and usually for only one trait. Significantly, not a single Rambouillet, Targhee or Columbia inbred line was superior (P less than .05) in overall merit to its appropriate selected control group. Unselected control group means tended to be slightly superior to means for most inbred lines for traits of low heritability (weaning weight, body type and body condition) and inferior for more highly heritable traits (staple length, face cover, and neck folds). Notably, only six of a total of 56 inbred lines were superior (P less than .05) in overall merit to their appropriate unselected control groups.

Animals↗
PubMedDate not supplied

[Gamma-glutamyltranspeptidase in chronic polyarthritis. I. Comparison with a control group and relationship with alkaline phosphatase].

Gamma-GT, alcaline phosphatase and other parameters of abnormal liver functions were estimated in 54 consecutive in-patients having active RA but without a previous history or clinical signs of liver disease, and compared with a matched control group, suffering from degenerative rheumatic disease. There was a slight to moderate elevation of gamma-GT in 40.4% of the RA-patients (mean value 27.2 IU/l) and in 32.1% (mean value 22.3 IU/l) of the control group, respectively. The difference was not significant. Abnormal values in the control group occurred mainly in patients with peri-arthropathia of the shoulder, before mobilisation under anaethetic (3 of 5) and - coxarthrosis before total hip replacement (4 of 12). Alkaline phosphatase was elevated in 25.9% of the RA-patients (mean value 41.3 +/- 21.9 IU/l) and in 14.8% of the control group (mean value 34.3 +/- 15.9 IU/l). The difference was significant. There was a correlation between gamma-GT and alcaline phosphatase in the RA-group (r = 0.549, p less than 0.001) but not in the control group (r = 0.102). Abnormal values found in the control group were mainly found among patients with osteoporosis, following fractures, and coxarthrosis. The frequency of abnormal results and the value of the means increased with raising disease activity. Two groups of 30 and 32 patients, respectively, were examined at intervals of 2 or 4 weeks over a period of 6-10 and 18 months, respectively, and showed temporary elevations os gamma-GT in 3/4 of all patients, of GOT in 2/3 of alcaline phosphatase in 1/2 and of GPT in 1/3. Compared with other parameters of liver disease gamma-GT did not react in a different but in a more sensitive way. In our opinion it is the most sensitive indicator of reactive changes of the liver in RA.

Adult↗
PubMed1996

Differential relationships of age and education to WAIS subtest scores among brain-damaged and control groups.

The 11 subtests of the WAIS were compared to the attribute variables of age and education in a brain-damaged group and a non-brain-damaged (control) group. Because of the validity information available for the WAIS, the subtests for the WAIS rather than the WAIS-R were studied. Data analyses compared the level of age and education (each group subdivided at the median) on WAIS subtest scores and the correlations between attribute variables and subtest scores. The results revealed a number of differences between the two groups, with age and education having a weaker and less consistent relation to WAIS subtest scores in the brain-damaged group than in the control group. The findings suggest that the relationships between attribute variables and psychological test scores are complex, and that adjusting or transforming raw scores for brain-damaged subjects according to tables based upon non-brain-damaged subjects may produce erroneous data.

Journal Article↗
PubMed1981

[Cardiorespiratory function in young bronchitis patients, mostly mineworkers, before and after kinesitherapy and exertion training. Comparison with a control group (Preliminary results)].

We have studied the effects of respiratory physiotherapy and physical training on the cardiopulmonary function of patients with early chronic bronchitis and broncho-obstruction presumably at the beginning stages. The trained group was compared with a control group who was treated with infra-red rays on the thorax. Both groups were treated during four weeks. All patients were less than 50 years old and all were smokers. They complained of dyspnea on exertion (stage 2 ECCS), cough and expectoration for at least one year. Their spirometry and airway resistance values were normal or near normal but at least two of the following functional indices were altered in all: the He residual volume, the slope of N2 phase III and/or the He bolus phase IV. In the trained group, functional indices of central or peripheral airway obstruction did not change after the four weeks of treatment. On the contrary, the slow vital capacity (SVC) and the peak expiratory flow (PEF), which are presumably more influenced by the force of respiratory muscles, were significantly increased after respiratory rehabilitation. During steady-state exercise of moderate intensity 1.) a slight increase of pH (P less than 0.1 at a VO2 of 1.5 l/min and 1.75 l/min), perhaps due to a lessened lactacidemia, 2.) a decrease in ventilation (VE) (P less than 0.1 at a VO2 of 1.25 l/min) and 3.) a reduction in the alveolo-arterial gradient (AaDO2) (P less than 0.1 at a VO2 of 1.25 l/min) were observed. In the control group there was no change of respiratory functional indices at rest or during exercise after treatment. The reduction of AaDO2 observed in the trained group could be due to an improvement of pulmonary gas exchange. This was small, however, and probably without clinical significance. We believe that the improvement of dyspnea noted in the trained group could be due to the increase in ventilatory performance (SVC, PEF and VE) and to a better O2 extraction in the peripheral muscles.

Adult↗
PubMed2003

Safety of hydroxychloroquine in pregnant patients with connective tissue diseases: a study of one hundred thirty-three cases compared with a control group.

OBJECTIVE: The use of hydroxychloroquine (HCQ) in pregnancy remains controversial. The recent demonstration that HCQ passes across the placenta, with cord blood concentrations nearly identical to those found in maternal blood, emphasizes the need for careful evaluation of pregnancies in women receiving HCQ. However, only small series of HCQ-treated pregnant women have been reported, and most of these studies had no control group. We now report our experience with 133 pregnancies in women being treated with HCQ, resulting in 117 live births. Results in the HCQ group are compared with those in a control group. METHODS: One hundred thirty-three consecutive pregnancies in 90 women treated with 200 mg of HCQ either twice daily (122 pregnancies) or once daily (11 pregnancies) were studied. These pregnancies were compared with 70 consecutive pregnancies in 53 women with similar disorders who did not receive HCQ. Electrocardiography was performed in 47 children of mothers treated with HCQ and in 45 children in the control group. RESULTS: Eighty-eight percent of pregnancies in the HCQ group and 84% of those in the control group ended successfully with a live birth. The outcomes of pregnancy were not statistically different between groups. One child in each group died of causes related to prematurity. Three malformations were observed in the HCQ group (1 hypospadias, 1 craniostenosis, and 1 cardiac malformation) versus 4 in the control group. On the electrocardiograms, the PR interval and the corrected QT interval were not statistically different between groups. No visual, hearing, growth, or developmental abnormalities were reported in any of the children at the last follow-up (ages 12-108 months; mean age 26 months). CONCLUSION: Our findings support preliminary evidence for the safety of HCQ therapy during pregnancy. This treatment probably should be maintained throughout pregnancy in patients with systemic lupus erythematosus.

Antirheumatic Agents↗
PubMed1992

The control group conundrum in chronic pain case/control studies.

The choice of an appropriate control group has been recognized as one of the most difficult problems in the methodology of case/control studies, both in theory and in practice. In the study of chronic pain, a "well control group" has frequently been employed. Although this design has intuitive appeal, it contains the potential for bias and error. In order to obtain the proper control group, the same exclusion criteria should be applied to cases and controls. Second, controls should be selected independently of exposure to the putative risk factors under investigation. To illustrate the nature of this problem we present two numerical examples, using a chronic pain disorder.

Case-Control Studies↗
PubMed2002

Tooth dimensions in hypodontia patients, their unaffected relatives and a control group measured by a new image analysis system.

Tooth dimensions were compared between index patients with severe hypodontia (six or more congenitally missing teeth), their relatives with a full complement of teeth, and a control group. The groups consisted of 12 index cases (seven females and five males), 21 relatives without hypodontia (13 females and eight males), and a control group of 10 males and 10 females with complete dentitions, and no family history of hypodontia. All formed teeth were imaged buccally and occlusally from study models, with a digital camera linked to a computer. The images were acquired and measured using Adobe Photoshop and Image Pro Plus, respectively. Mesiodistal, buccolingual, or occlusogingival area and perimeter measurements were determined from each image. In the index hypodontia group tooth dimensions were significantly smaller (P < 0.001, Bonferroni corrected level) for maxillary and mandibular canines, and first premolars for all dimensions from the buccal view, and for maxillary and mandibular canines and first premolars, maxillary central incisors, maxillary first molars, mandibular lateral incisors, and mandibular second premolars for all dimensions from the occlusal view. In the relatives without hypodontia compared with the control group, mesiodistal dimensions from the buccal view were significantly smaller (P < 0.001) for the central incisors and maxillary first and second premolars, and for the maxillary and mandibular first premolars for all dimensions from the occlusal view. There was a trend for the tooth dimensions of all teeth in the index group to be smaller compared with the control group. The tooth dimensions of the relatives without hypodontia also tended to be smaller than the control group, but were larger than those of the index cases.

Analysis of Variance↗
PubMed1998

[Prophylactic and therapeutic effects of beclomethasone inhalation on bronchial hyperresponsiveness and asthma: a randomized, double-blind, parallel-group controlled trial].

OBJECTIVE: To better understand the effects of corticosteroid inhalation on asthma and asymptomatic bronchial hyperresponsiveness (BHR). METHODS: A double blind, randomized study was conducted to compare the effects of beclomethasone dry powder (BDP, 600 micrograms/day) inhalation with placebo on BHR and asthmatic symptoms in 59 students (12-18 yrs) for one year. RESULTS: After one year of treatment, lgPD20-FEV1 increased significantly in asthmatics in the BDP group (0.385 +/- 0.424 vs 1.187 +/- 0.603 mumol histamine). Thirty percent of asthmatics in BDP group and 86% in the control group developed symptoms in this year (P = 0.076). There was no significant difference in lgPD20-FEV1 between the BDP and the control group in asymptomatic BHR students. However, none in the BDP group of asymptomatic BHR students developed asthmatic symptoms compared with 3 cases (15%) in control group. The accumulative symptom score showed significant difference between the BDP group and the control group in asymptomatic BHR students (1.50 +/- 2.54 vs 5.58 +/- 6.22, P < 0.01). CONCLUSION: The results suggested that BDP could significantly relieve the severity of BHR and symptoms in asthmatics, and could have some prophylactic effects on the development of asthma in those with asymptomatic BHR.

Administration, Inhalation↗
PubMed2005

[Comparison of health-related quality of life between patients with rheumatic diseases and a control group].

OBJECTIVE: To compare the health-related quality of life between patients with rheumatoid arthritis and systemic lupus erythematosus and a control group. METHODS AND MATERIAL: Eighty-eight patients with rheumatoid arthritis, 40 patients with systemic lupus erythematosus and 40 women who did not suffer from any inflammatory joint disease (control group) participated in this comparative study. The questionnaires they completed included information about their sociodemographic status and comorbidities. Patients with rheumatoid arthritis and systemic lupus erythematosus were assessed for pain (visual analogical scale), extra-articular manifestations, and disease activity; also they completed questionnaires for the evaluation of physical function (Health Assessment Questionnaire--HAQ) and burden of arthritis (Arthritis Impact Measurement Scale). All groups under investigation completed the health-related quality questionnaire SF-36 (Medical Outcomes Study Short Form-36) validated in Lithuania. RESULTS: The study of health-related quality of life of women with rheumatic disease showed that patients with systemic lupus erythematosus had stronger pain (p=0.017). It was also found that the activity of patients with rheumatoid arthritis was more limited because of emotional problems (p=0.038). No significant differences were found in other areas of life quality. It was recognized that in comparison to other groups, the quality of life of the control group was better (p=0.000) from the point of view of physical activity, limitations of activity because of physical problems, pain, overall health status and social relations. The psychological status of the latter was undoubtedly worse. CONCLUSIONS: In this study it was found that all patients with rheumatoid arthritis and systemic lupus erythematosus had evaluated most of the aspects of health-quality very similarly. Significant differences have been determined when assessing pain and limitation of activity because of emotional problems. The health-related quality of life of the control group is definitely better than that of the rest in most aspects, except for the psychological one.

Activities of Daily Living↗
PubMed2005

[Adaptation of health-related quality of life ("SF-36") questionnaire, its validation and assessment of performance for control group and patients with rheumatoid arthritis].

OBJECTIVE: To adapt the Lithuanian "SF-36" questionnaire, to assess psychometric and life quality criteria for patients with rheumatoid arthritis and for control group. MATERIAL AND METHODS: Linguistic and cross-cultural adaptation of the Lithuanian "SF-36" questionnaire was made on the basis of the stages referred to in the international project of health quality assessment. For the evaluation of psychometric criteria, data from Vilnius rheumatoid arthritis register (502 patients) and those of the control group (83 people) were used. The reliability of "SF-36" questionnaire was assessed by determining homogeneity, internal consistency of scales and scale stability in time and by calculating the intraclass correlation coefficient. Face, contents and construct validity of the "SF-36" questionnaire has been evaluated, as well as the quality of life of patients with rheumatoid arthritis and those of the control group. RESULTS: After making linguistic and cultural adaptation of the questionnaire, its final version has been prepared. In assessing the homogeneity of "SF-36", a high and middle-sized correlation between different items of the questionnaire has been noticed in the control group (r=0.51-0.71) and in patients with rheumatoid arthritis (r=0.57-0.83). Internal consistency for the items was also good enough (Kronbach alpha=0.79-0.85) for both tested groups. Stability in time was high for all items of the questionnaire, for the exception of vitality (r=0.074). Face and contents validity of the questionnaire is rather good. Estimates of the correlation between items of the quality of life questionnaire and other questionnaires have shown good convergent and discriminant construct validity. Evaluations of the quality of life in almost all spheres, except emotional, by patients with rheumatoid arthritis were worse than by the rest. CONCLUSIONS: Questions of health-related quality of life questionnaire are easy to understand and acceptable for the respondents. Reliability and validity of the questionnaire is rather high. For the exception of emotional status, quality of life in almost all spheres was considered as bad by patients with rheumatoid arthritis. The control group had more complaints about the emotional status.

Arthritis, Rheumatoid↗
PubMed2003

Measuring learning using an untrained control group: comment on R. Reber and Perruchet.

R. Reber and Perruchet (this issue) argue that use of control groups without training is unsound for establishing that learning has occurred. We show that inferring learning from a difference between a trained group and an untrained control in no way relies on their implausible additivity assumption, and that untrained control groups can be an invaluable aid to the researcher.

Adult↗
PubMed2005

Prospective, randomized, multicentric, open, comparative study on the efficacy of a prophylactic single dose of 500 mg levofloxacin versus 1920 mg trimethoprim/sulfamethoxazole versus a control group in patients undergoing TUR of the prostate.

OBJECTIVES: Transurethral resection of the prostate (TUR-P) is one of the most frequent urological procedures. The efficacy of a prophylactic single dose of levofloxacin vs. trimethoprim/sulfamethoxazole (TMP/SMZ) vs. a control group, receiving no antibiotic prophylaxis, in patients undergoing TUR-P was investigated in a multicentre study. The aims were to assess the rate of bacteriuria (cfu> or =10(4)/ml) 5 to 7 days, and 3 to 5 weeks after TUR-P, as well as postoperative complications. METHODS: The study was prospective, randomized, multicentric, open and comparative. Patients without bacteriuria (cfu<10(4)/ml) scheduled for TUR-P and not having received antibiotics prior within four days were enclosed. Patients received an oral single dose prophylaxis with either 500 mg levofloxacin, or 320/1600 mg TMP/SMZ, or no prophylaxis according to a 2:2:1 randomization. Clinical examination of the patients and urine culture were performed prior to, 5 to 7 days and 3 to 5 weeks after TUR-P. RESULTS: 14 urological centres throughout Germany recruited 400 patients. 376 patients were evaluable until day 5 to 7, 339 until week 3 to 5. Overall bacteriuria rate at day 5 to 7 was 22% (levofloxacin 21%; TMP/SMZ 20%; control group 30%). Bacteriuria rate at week 3 to 5 was 28% (levofloxacin 26%; TMP/SMZ 26%; control group 36%). Complication rate at week 3 to 5 was 10% (levofloxacin 8%; TMP/SMZ 10%; control group 16%). The rates of postoperative bacteriuria ranged widely between centers (0%-75%). Statistically significant (p<0.05) risk factors for bacteriuria (range) were qualification of surgeon (19%-37%), presence of a suprapubic catheter (22%-34%), disconnection of the closed drainage system (25%-52%), operating time (12%-31%) and operative centre (0%-75%). Total antibiotic consumption (for prophylaxis and treatment) in the control group was higher and more expensive than in groups with antibiotic prophylaxis (6.9 vs. 5.0 doses/patient; 24.9 vs. 19.7 /patient) (p<0.0001). Postoperative complications in patients with bacteriuria (cfu> or =10(4)/ml) were more frequent than in non bacteriuric (cfu<10(4)/ml) patients (17% vs. 8%) (p<0.01). CONCLUSIONS: It is debatable whether postoperative bacteriuria is the key parameter to define efficacy of antimicrobial prophylaxis in patients undergoing TUR-P. The rate of bacteriuria, however, correlated well with the overall rate of postoperative complications. Therefore, it seems reasonable to lower the rate of bacteriuria by prophylaxis. Since patients without antibiotic prophylaxis received at the end even more antibiotic doses than patients with prophylaxis, the overall selection pressure by antibiotic usage can obviously not be lowered by resigning prophylaxis. Therefore we conclude that at least patients at risk should receive antibiotic prophylaxis prior to TUR-P.

Aged↗
PubMed2002

Are patients with bipolar affective disorder socially disadvantaged? A comparison with a control group.

BACKGROUND: Bipolar affective disorder (BPAD) has considerable implications for personal and social functioning. However a tendency to be over-represented in high socio-economic classes has been reported in earlier studies, suggesting that social disadvantage accompanying the illness is not severe. In addition, an association between affective disorders in general and increased residential mobility has been suggested, but it is unclear if such an association exists with BPAD. OBJECTIVES: (1) To investigate the suggestion made in previous studies that patients with bipolar disorder are advantaged socially. (2) To test the hypothesis that patients with bipolar disorder show greater residential mobility compared with other patients with psychiatric disorders. METHODS: Ninety patients with DSM IV diagnosis of bipolar disorder admitted to the acute in-patient unit of a public-financed district psychiatric service in Dublin were compared with a control group of 91 randomly selected patients with other psychiatric diagnoses, excluding schizophrenia. Socio-economic, educational and employment ratings were compared, and also duration of illness, frequency of admission and residential mobility. The data were collected retrospectively from case notes and through semistructured interviews with patients or their relatives. The bipolar group was compared with the control group and to the unipolar depression subgroup. RESULTS: The bipolar and control groups were found to have similar demographic and socio-economic features, although the bipolar group had more years of education compared with the whole control group but not when compared with the unipolar depression group. The bipolar group showed longer duration of psychiatric disorder, more frequent hospital admissions and more frequent residential moves since the onset of the illness. CONCLUSION: Bipolar patients requiring in-patient care in this service experience severe disruption to their lives over prolonged periods.

Adult↗
PubMed1997

Clinical characteristics of patients with motor disability due to conversion disorder: a prospective control group study.

OBJECTIVES: Previous studies have suggested associations between conversion and many different clinical characteristics. This study investigates these findings in a prospective design including a control group. METHODS: Thirty consecutive patients with a recent onset of motor disability due to a conversion disorder were compared with a control group of patients with corresponding motor symptoms due to a definite organic lesion. Both groups had a similar duration of symptoms and a comparable age and sex profile and were assessed on a prospective basis. Background information about previous somatic and psychiatric disease was collected and all patients were assessed by means of a structured clinical interview linked to the diagnostic system DSM III-R, the Hamilton rating depression scale, and a special life events inventory. RESULTS: The conversion group had a higher degree of psychopathology with 33% of the patients fulfilling the criteria for psychiatric syndromes according to DSM-III-R axis I, whereas 50% had axis II personality disorders compared with 10% and 17% respectively in the control group. Conversion patients also had significantly higher scores according to the Hamilton rating depression scale. Although patients with known neurological disease were not included in the conversion group, a concomitant somatic disorder was found in 33% of the patients and 50% complained of benign pain. The educational background in conversion patients was poor with only 13% having dropped out of high school compared with 67% in the control group. Self reported global assessment of functioning according to the axis V on DSM IV was significantly lower in conversion patients, who also registered significantly more negative life events before the onset of symptoms than controls. Logistic regression analysis showed that low education, presence of a personality disorder, and high Hamilton depression score were significantly associated with conversion disorder. CONCLUSION: The importance of several previously reported predisposing and precipitating factors in conversion disorder is confirmed. The results support the notion that conversion should be treated as a symptom rather than a diagnosis and that efforts should be made in diagnosing and treating possible underlying somatic and psychiatric conditions.

Adult↗